fighting entropy is always a losing battle.  Most people would rather have
comfort than freedom.  The paradox is that you can't really have the former,
in the long term, unless you have the latter.
One of the reasons that I probably come across to some people as a weird
cross between a libertarian and an "establishment tool" is that I end up
taking an utterly pragmatic view of government.  I don't get up in arms when
the government fails to protect the interests of the people, because in my
lifetime it never has--therefore, I have no expectation that it will.
As a result, I protect my own interests rather than expecting the government
to be "fair".  I will use strong cryptography when I think it is needed,
whether or not it is legal at the time.  Same thing with anything else the
government would rather not see in private hands--that's their problem.
What's important to me is using the right tool for the job.  If it's legal,
so much the better.  If it is not, but does not violate my (very strong)
sense of personal ethics, I will use it anyway as long I think it is worth
it.  Expecting the government to actually protect the interests of its
citizens, except by accident, is utter folly.  Even Jefferson, one of the
major architects of the American system of government, figured that in a
couple hundred years it would become so corrupt and self-serving that it
would be time dismantle it and try again, by revolution if necessary.  I
agree, and while I don't go around trying to spark one, I'll certainly
participate if it happens when I'm around.  There is a reason I am such a
strong supporter of individual rights while being so cynical about politics.
I've already written off politics.
And yes, this may get me in trouble some day.  If so, so be it.  I drive
faster than 55 MPH, too.
Amanda Walker
InterCon Systems Corporation
From: grady@netcom.com (1016/2EF221)
Subject: Re: The [secret] source of that announcement
Organization: capriccioso
X-Newsreader: TIN [version 1.1 PL6]
Distribution: inet
Lines: 84
Andrew Molitor (amolitor@nmsu.edu) wrote:
:
: 	1) Monitor my phonecalls.
: 	2) Monitor usenet.
: 	3) Provide only cryptosystems they can easily crack.
: 	4) etc etc.
:
: 	This is not to say that they *don't*, they might. But you don't
: know that they do, and you have no evidence that they do, for almost
: all values of you. It follows, therefore, that for most values of 'you',
: your claims about the NSA border on paranoia.
:
: 	Andrew
Now I wouldn't be the one to claim that you are injecting some
disinformation into the net, Andrew, but 'paranoia' refers to
unwarranted or excessive suspicions or fear, not those that
have reasonable roots.
Let's start with looking at the professionals, the NSA itself.
Its birth was by secret executive order by Harry S Truman
in 1952.  Until even 1976 not even one word of this executive
order chartering the NSA was sealed.  Paranoia, right?
On the outside of the NSA complex is a ten foot Cyclone fence
with multiple rows of barbed wire, with high voltage, complete with signs
prohibiting even making sketches under penalty of the Internal
Security Act.  The area is completely scanned by closed circuit
television.  More paranoia.
These are professionals,  Maybe they know something we don't, eh?
Do you think it would have helped Admiral Yamamoto if the Japanese
had been a little more 'paranoid' of their purple cipher?
Or maybe the Germans should have been a little more 'paranoid' about
their Engima with respect to Turing and the British.
How about the cracking of the Zimmerman telegram?  Would a little
more paranoia have helped the Germans here?
Maybe the NSA should have been a little more 'paranoid' about
Emma Woikin, or Joseph Sidney Petersen, Jr., or  ...
Maybe you want to talk about Macmillan publishers cooperation
with the CIA and NSA to suppress Yardley's Japanese Diplomatic
Secrets or even Kahn's The Codebreakers.. paranoia, right?
The most popular cipher systems in captured soviet spies was
the one-time pad, even with the necessity of keeping incriminating
evidence about, is known to be the only proven unbreakable system.
Soviet paranoia, right?
And what do you think the NSA does with its Wullenwebers?  And
huge Rhombics pointed embassy row?  And their sites near
satellite uplink and downlink sites?  Duh.
When I worked in a classified MITRE communications lab at one time
even with a "secret" clearance I had to be escorted to the toilet
and the entire site was built INTO a Mosler-type vault with *very*
thick bomb-proof door.  MITRE paranoia?
I could cite probably a hundred more facts which all support, as
best hypothesis, the notion that the NSA is grabbing as much as
it can, as fast as it can.  One would be a fool to ignore the
pattern of facts and conclude that they were random...
And we know the government is violent -- even against children as
recent events prove.  Judge William Sessions is a disgrace
but a solemn warning to those who ignore the web of evidence
that our government institutions have in their contempt for our
civil rights.
And of course we have to err somewhat on the excessive side of
caution because that does much less harm than erring on the
reckless side. As member of the crew of the USS Liberty might aver.
I might suggest, Andrew, that you read Kahn's Codebreakers and
Bamford's Puzzle Palace and come back with some more facts to
support your sheepish acquiescence to authority.
--
grady@netcom.com  2EF221 / 15 E2 AD D3 D1 C6 F3 FC  58 AC F7 3D 4F 01 1E 2F
Subject: Re: Clipper considered harmful
From: yuan1@scws7.harvard.edu (Nina Yuan)
Distribution: inet
Nntp-Posting-Host: scws7.harvard.edu
Lines: 37
shirriff@sprite.berkeley.edu (Ken Shirriff) writes:
>It seems likely to me that that a large subset of encrypted communications
>would be archived to tape so they could be read if sometime in the future
>probable cause arises and a warrant is obtained.  I can even imagine this
>being found legal and constitutional, since nothing is actually listened to
>until a valid warrant is issued and the keys are obtained.
>Imagine archiving all pay-phone conversations, so if someone turns out
>to be a drug dealer, you can listen to all their past drug deals.  And
>archive calls to/from suspected Mafia members, potential terrorists,
>radicals, etc.  Imagine the convenience for the police of being able to
>get a warrant now and listening to all the calls the World Trade Center
>bombers made in the past year.
Imagine if this were available during the 1992 elections; instead of
clumsily searching through the Clinton passport file, they could have
just done a "voice-grep" (as someone stated earlier) on his telephone
conversations for the last 10 years.
I'm not a lawyer and I don't even play one on TV, but intuitively there's
something wrong with having one's words archived for possible future
use against you.  This possibility frightens me more than any of the
talk about the Clipper Chip, right to cryptography, etc.
>Since archiving would be such a powerful tool and so easy to do, why
>wouldn't it happen?
I'm afraid it just might.
-nhy
--
----------------------------------------------------------------------------
Nina H. Yuan                               "It's a miracle that curiosity
Harvard College                             survives formal education."
yuan1@husc.harvard.edu                                  - Albert Einstein
From: mcbay@clam.com (George McBay)
Subject: Re: What the clipper nay-sayers sound like to me.
Distribution: na
Organization: Clam Associates
Lines: 21
In article <1qsvfcINNq9v@dns1.NMSU.Edu> amolitor@moink.nmsu.edu (Andrew Molitor) writes:
[A lot of this article has been deleted for space.]
>   Look! This is clearly the first step toward outlawing our
>   own screw thread specifications. If this madness isn't fought,
>   tooth and nail, every step of the way, it'll be a crime to use
>   screw threads other than those our Fearless Leaders so *graciously*
>   define for us.
The Clipper standard *is* the first step toward outlawing other
strong encryption standards.  If the government didn't intend to outlaw
other forms of encryption, than Clipper is just a big waste of time and money.
Why, you ask?  Because anyone who is transferring data that any government
agency could use against him/her would be a total fool to use the Clipper
system..So why add the backdoor-key if all lawbreakers will use alternate
encryption methods? Because they assume they can just do away with everything
else.
I, for one, am planning on boycotting any equipment that contains
clipper technology.
From: jhan@debra.dgbt.doc.ca (Jerry Han)
Subject: Re: Once tapped, your code is no good any more.
Nntp-Posting-Host: debra.dgbt.doc.ca
Organization: Communications Research Centre, Ottawa
Distribution: na
Lines: 58
In article <bontchev.735404289@fbihh>
bontchev@fbihh.informatik.uni-hamburg.de writes:
>And some people thought that I am exaggerating when claiming that the
>Cripple Chip is just a first step in a totalitarian plot against the
>civil liberties in the USA... It seems that I've even been an optimist
>- the things are happening even faster than I expected.... That's
>another of the dirty tricks they used to apply on us under the
>communist regime - do something secret, THEN tell the people about is
>(after the fact, when nothing can be done any more), and of course,
>explaining them how much better the situation is now...
>
>In my previous messages I wrote that the Americans should wake up and
>fight against the new proposal. Now it seems to me that it is already
>too late - it has already happened, the civil liberties have been
>violated, no, stollen from the American people, while the most part of
>this people has been sleeping happily... :-((( Too sad...
As one of the happily sleeping people, I would just like to ask this->
aren't people just slightly overreacting to this?  Or are we all of a
sudden going to draw parallels to Nazi Germany and Communist Russia?
The point of the matter is that; yes this is a serious problem.  But it is
not the end of the world.  Guess what?  We're doing something now you
can't do in a Communist country or Nazi Germany.  We're complaining about
it, (or rather, you're complaining about it) and nobody is shooting at us.
(Or, rather, if they're shooting at me, they have real bad aim.  (:-) )
GUESS WHAT PEOPLE?  You live in one of the few countries in the world
where a person can complain without getting shot at.
People are always complaining that somebody did this wrong, or somebody
did that wrong, or whatever.  Sit down and figure out two things:
1)  What have they done right?
2)  How much worse can it get?
And you'll find that you and I, are pretty damn lucky.
So let's talk about it, get some action going, decide what's going on.
But let's not overreact!
>
>Regards,
>Vesselin
>--
>Vesselin Vladimirov Bontchev          Virus Test Center, University of Hamburg
>Tel.:+49-40-54715-224, Fax: +49-40-54715-226      Fachbereich Informatik - AGN
>< PGP 2.2 public key available on request. > Vogt-Koelln-Strasse 30, rm. 107 C
>e-mail: bontchev@fbihh.informatik.uni-hamburg.de    D-2000 Hamburg 54, Germany
--
Jerry Han-CRC-DOC-Div. of Behavioural Research-"jhan@debra.dgbt.doc.ca"
///////////// These are my opinions, and my opinions only. \\\\\\\\\\\\\
\\\\\\\\\ A proud and frozen member of the Mighty Warriors Band ////////
"Memories of those I've left behind, still ringing in my ears."-Genesis-
From: rlglende@netcom.com (Robert Lewis Glendenning)
Subject: Re: Organized Lobbying for Cryptography
Organization: Netcom - Online Communication Services (408 241-9760 guest)
Lines: 21
Generally, an organization has influence in proportion to:
The narrowness of its objectives
The number of members
The strength of belief of its members
This is why the pro- and anti-abortion groups are so strong: narrow objectives,
lots of interested members who are real passionate.
For this reason, mixing with the NRA is probably a bad idea.  It diffuses
the interests of both groups.  It may well diminish the Passion Index
of the combined organization.  It is not clear it would greatly enlarge
the NRA.
So, I believe a new organization, which may cooperate with NRA where the
two organization's interest coincide, is the optimum strategy.
lew
--
Lew Glendenning		rlglende@netcom.com
"Perspective is worth 80 IQ points."	Niels Bohr (or somebody like that).
From: rdippold@qualcomm.com (Ron "Asbestos" Dippold)
Subject: Re: Do we need the clipper for cheap security?
Originator: rdippold@qualcom.qualcomm.com
Nntp-Posting-Host: qualcom.qualcomm.com
Organization: Qualcomm, Inc., San Diego, CA
Lines: 36
gtoal@gtoal.com (Graham Toal) writes:
>Can someone tell me if hardware compression is or is not needed to run
>digital speech down 14.4K?  I think it is; I've heard it's not.  Lets
>say 8 bit samples.  Would *raw* data at the corresponding sampling rate
>be usable?  If not, how fancy does the compression need to be?
A good vocoder like ours will give you 8000 bits per second locked at
full rate (it's a variable rate voice activity vocoder).  If you want
less quality, cut that to 4000 bps (half rate).  At full rate variable
you could put two full-duplex conversations on a V.32bis modem.  This
requires a DSP or ASICs, though.  An RS-6000 has a CPU that could
probably do it in real-time, because it has the add-and-multiply
instruction and a few other DSP things.
If you want to do speech in real-time you need about 4000 samples a
second (for not very good voice) with your 8 bit samples (ISDN is 8000
8-bit samples a second), which is 32 kbps.  You could do a fast 2:1
compression on that to get it down to 16 kbps, which is just about
V.32bis.  The quality at this point is very bleah, but it should work.
Now add in the time for your encryption method.  You're going to need
sampling hardware, which is no problem on a new Mac, an Amiga.  Or a
PC with a SoundBlaster card (just because they're so popular and cheap
- you could also build a simple ADC).  The problem with the
SoundBlaster is that it doesn't seem to be full duplex - you can't
sample and play backq at the same time, making a two-way conversation
a bit tough.  The special hardware or a more capable sound card may be
required.
The only thing that worries me is that 2:1 compression - the
SoundBlaster can do it automatically in hardware, but other than that
I don't have a good feel for how processor intensive it is, so I can't
estimate how fast a PC you'd need.
--
Not all men who drink are poets.  Some of us drink because we are not poets.
From: vjs@rhyolite.wpd.sgi.com (Vernon Schryver)
Subject: Re: Fighting the Clipper Initiative
Organization: Silicon Graphics, Inc.  Mountain View, CA
Lines: 20
In article <strnlghtC5toC6.KIu@netcom.com>, strnlght@netcom.com (David Sternlight) writes:
> ...
>                                  The Federal Reserve Open Market Committee
> has successfully kept decisions from leaking for the statutory period until
> publication.
How are you sure of that?  Weren't there some recent studies that
found corelations between not-yet announced decisions and market changes?
Aren't there continuing early rumors of their deliberations?
>              Even the Department of Agriculture has successfully kept crop
> forecasts from leaking prematurely.
Sheesh!  Remember the big scandal a year or two (or 3?) ago about
exactly such leaks?
Vernon Schryver,  vjs@sgi.com
From: rab@well.sf.ca.us (Bob Bickford)
Subject: Re: Off the shelf cheap DES keyseach machine
Nntp-Posting-Host: well.sf.ca.us
Organization: Whole Earth 'Lectronic Link
Lines: 32
In article <TOM.93Apr21114536@amber.ssd.csd.harris.com>,
tom@ssd.csd.harris.com (Tom Horsley) writes:
>
>This isn't intended to be a flame or anything, I am just really curious
>how to manufacture these things while still maintaining the key escrow
>security without simply saying "trust the manufacturer, they won't look".
Without getting into the *really* *thorny* questions about reverse
engineering and all of that, let me just point out that there already
exist gate arrays and suchlike that have what's known as a security fuse
which can be programmed after you've verified all other programming --
this makes it impossible to read out the programming of the device
(again, ignoring the reverse engineering questions).  Speaking from
experience here: I had to completely reinvent one of my designs some
six or seven years ago when the disk file was zapped, the backups were
all bad, and the devices were unreadable because of the security fuses.
Made me appreciate the value of printouts.  ;-)
So on this point at least there's not so much worry.
But whether or not we can get the chips made reliably and securely is
really secondary to the question of whether use of the chip is itself
likely to be secure, methinks.
--
Robert Bickford      "A Hacker is any person who derives joy from
rab@well.sf.ca.us    discovering ways to circumvent limitations." rab'86
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
"I recognize that a class of criminals and juvenile delinquents has
taken to calling themselves 'hackers', but I consider them irrelevant
to the true meaning of the word; just as the Mafia calls themselves
'businessmen' but nobody pays that fact any attention."            rab'90
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
From: ab@ersys.edmonton.ab.ca (Allan Brockman)
Subject: I don't have FTP, live in Canada, how do i get RSA(RAS?) 4 my atariS
Organization: Edmonton Remote Systems #3, Edmonton, AB, Canada
Lines: 9
i don't have FTP and i live in canada ( this means that it would be
illeagle for a U.S. citizen to send the program to me. their gigerment
wishes to restrict its dispersil ) but someone in europe must have ported
a coppy of RSA to the atariST by now.  how do i get a coppy of the RSA
from a non-FTP news feed?
--
Allan Brockman              ab@ersys.edmonton.ab.ca
From: wcs@anchor.ho.att.com (Bill Stewart +1-908-949-0705)
Subject: Re: THE CLIPPER CHIP: A TECHNICAL SUMMARY
Organization: Brought to you by the numbers 2, 3, and 7
In-Reply-To: denning@guvax.acc.georgetown.edu's message of 19 Apr 93 18:23:27 -0400
Nntp-Posting-Host: rainier.ho.att.com
Lines: 62
In article <1993Apr19.182327.3420@guvax.acc.georgetown.edu> denning@guvax.acc.georgetown.edu writes:
[Prof. Denning's description of SkipJack mostly omitted]
CHIP STRUCTURE
The Clipper Chip contains a classified 64-bit block encryption
algorithm called "Skipjack."  The algorithm uses 80 bit keys (compared
with 56 for the DES) and has 32 rounds of scrambling (compared with 16
for the DES).  It supports all 4 DES modes of operation.  Throughput is
16 Mbits a second. [...]
F, an 80-bit family key that is common to all chips
N, a 30-bit serial number
U, an 80-bit secret key that unlocks all messages encrypted
with the chip
The key K and message stream M (i.e., digitized voice) are then
fed into the Clipper Chip to produce two values:
E[M; K], the encrypted message stream, and
E[E[K; U] + N; F], a law enforcement block.
Three questions:
1) It looks like each 64 bits of input gives you 4*64 bits of output:
E[M;K] = 64 bits
E[K;U] = E[ 80 bits ] = 128 bits
E[ E[K;U], N ; F ] = E[ 128 + 30 bits ] = 192 bits
Do you really need to transmit all 256 bits each time,
or do you only transmit the 192 bits of wiretap block at the beginning?
All 256 would be really obnoxious for bandwidth-limited applications
like cellular phones (or even regular phones over
2) how do the 4 DES modes interact with the two-part output?
Do the various feedback modes only apply to the message block,
or also to the wiretap block?  Or, if the wiretap block is only
transmitted at the beginning, does it get incorporated into
everything through feedback modes, but not during ECB mode?
3) Does the Clipper Chip check the wiretap block itself?
Does the block have to be present at all?
Since the receiving chip doesn't know the transmitter's U,
it presumably can't check the validity of E[K;U], so it's
limited to checking the *form* of the wiretap block,
and maybe checking the serial number for reasonableness
(unless there's some sort of back-door structure that lets
it recognize a valid E[K;U].)
In that case, can you replace the wiretap block with a DIFFERENT
wiretap block, presumably an old valid one to avoid attracting attention?
(The chip won't do it, so you postprocess the output.)
Regular people can do one with their own serial number and a dummy key;
paranoid people can use someone else's serial number.
On the other hand, if I could think of that solution so easily,
presumably the NSA could too - have they done something to block it,
like use message encryption that's really E[M; K,U,N] ?
Thanks!
--
#				Pray for peace;      Bill
# Bill Stewart 1-908-949-0705 wcs@anchor.att.com AT&T Bell Labs 4M312 Holmdel NJ
#	              No, I'm *from* New Jersey, I only *work* in cyberspace....
# White House Commect Line 1-202-456-1111  fax 1-202-456-2461
From: elee9sf@menudo.menudo.UH.EDU (Karl Barrus)
Subject: Re: Once tapped, your code is no good any more.
Organization: University of Houston
Lines: 27
Distribution: na
<strnlghtC5nrHw.1qB@netcom.com>
NNTP-Posting-Host: menudo.uh.edu
In-reply-to: strnlght@netcom.com's message of Sun, 18 Apr 1993 02:41:55 GMT
David Sternlight writes:
> I'd trust something from the NSA long before I'd trust something from
> some Swiss or anbody Japanese.
What???  This is an incredible statement!  The NSA tried to suppress
public key crypto and RSA, and yet they claim to encourage use of
strong crypto for US citizens.
Would you trust a black-box from the NSA versus an "open system" from
elsewhere?
/-----------------------------------\
| Karl L. Barrus                    |
| elee9sf@menudo.uh.edu             | <- preferred address
| barrus@tree.egr.uh.edu (NeXTMail) |
\-----------------------------------/
--
/-----------------------------------\
| Karl L. Barrus                    |
| elee9sf@menudo.uh.edu             | <- preferred address
| barrus@tree.egr.uh.edu (NeXTMail) |
\-----------------------------------/
From: mjr@tis.com (Marcus J Ranum)
Subject: Re: Off the shelf cheap DES keyseach machine (Was: Re: Corporate acceptance of the wiretap chip)
Organization: Trusted Information Systems, Inc.
Lines: 10
NNTP-Posting-Host: sol.tis.com
>I mean, if we can imagine the
>machine that does 1 trial/nanosecond, we can imagine the storage medium
>that could index and archive it.
I think you'd have to do some massive data compression just to
fit a bit of key information on each primary particle of the known
universe.
But, hey, it's fun to imagine.
mjr.
From: smhanaes@gpu.utcc.utoronto.ca (D. Wigglesworth)
Subject: freely distributable public key cryptography c++ code:  where?
Summary: Do you know?
Organization: UTCC Public Access
Lines: 8
Do you know of any freely distributable c++ (or c) code for public
key cryptography (such as RSA)?
I've tried various archie searches to no avail.
Thanks,
Dan
From: rboudrie@chpc.org (Rob Boudrie)
Subject: Re: Once tapped, your code is no good any more.
Organization: Center For High Perf. Computing of WPI; Marlboro Ma
Distribution: na
Lines: 26
In article <C5so84.Hxv@demon.co.uk> Graham Toal <gtoal@gtoal.com> writes:
>In article <2073@rwing.UUCP> pat@rwing.UUCP (Pat Myrto) writes:
>:If the Clinton Clipper is so very good, why not make its algrithm public
>:so many people can exchange ideas and examine it, rather than a few
>:isolated 'respected experts' (respected by whom?  for what?  Perhaps a
One more time...
If they released the algorithm, it would be possible for someone
to come up with an implementation which was identical, but
lacking an escrowed key.
Note that the press announcement mentioned that the algorithm was
being kept secret for security of the key escrow system.  In this
case security means "an escrowed key for EVERY clipper chip".
Assuming you believed all that is said about the effective of
the algorithm, and the escrow system, which would you buy :
(a)  Chip from firm A with the escrowed key
(b)  Second source chip from reputable firm B with no key
in government escrow.
There would obviously be powerful economic incentives for a second
source, non escrowed, vendor.
From: bontchev@fbihh.informatik.uni-hamburg.de (Vesselin Bontchev)
Subject: Re: Once tapped, your code is no good any more.
Reply-To: bontchev@fbihh.informatik.uni-hamburg.de
Organization: Virus Test Center, University of Hamburg
Distribution: na
Lines: 33
andersom@spot.Colorado.EDU (Marc Anderson) writes:
> methods.  ``This year's crime bill will have teeth, not bare gums,''
> Clinton said.  In particular, his administration will place strict
> controls on data formats and protocols, and require the registration
> of so-called ``cryptographic keys,'' in the hope of denying drug
> dealers the ability to communicate in secret.  Clinton said the
> approach could be used for crackdowns on other forms of underground
> economic activity, such as ``the deficit-causing tax evaders who
> live in luxury at the expense of our grandchildren.''
And some people thought that I am exaggerating when claiming that the
Cripple Chip is just a first step in a totalitarian plot against the
civil liberties in the USA... It seems that I've even been an optimist
- the things are happening even faster than I expected.... That's
another of the dirty tricks they used to apply on us under the
communist regime - do something secret, THEN tell the people about is
(after the fact, when nothing can be done any more), and of course,
explaining them how much better the situation is now...
In my previous messages I wrote that the Americans should wake up and
fight against the new proposal. Now it seems to me that it is already
too late - it has already happened, the civil liberties have been
violated, no, stollen from the American people, while the most part of
this people has been sleeping happily... :-((( Too sad...
Regards,
Vesselin
--
Vesselin Vladimirov Bontchev          Virus Test Center, University of Hamburg
Tel.:+49-40-54715-224, Fax: +49-40-54715-226      Fachbereich Informatik - AGN
< PGP 2.2 public key available on request. > Vogt-Koelln-Strasse 30, rm. 107 C
e-mail: bontchev@fbihh.informatik.uni-hamburg.de    D-2000 Hamburg 54, Germany
From: bontchev@fbihh.informatik.uni-hamburg.de (Vesselin Bontchev)
Subject: Re: Would "clipper" make a good cover for other encryption method?
Reply-To: bontchev@fbihh.informatik.uni-hamburg.de
Organization: Virus Test Center, University of Hamburg
Lines: 17
strnlght@netcom.com (David Sternlight) writes:
> Some of the more notorious self-styled dissidents here, for example, have
> already got their heads so high above the tall grass that they'd have little
> chance of getting a clearance.
If there are many as..., er, people in the USA who reason like the
above, then it should not be surprising that the current plot has been
allowed to happen...
Regards,
Vesselin
--
Vesselin Vladimirov Bontchev          Virus Test Center, University of Hamburg
Tel.:+49-40-54715-224, Fax: +49-40-54715-226      Fachbereich Informatik - AGN
< PGP 2.2 public key available on request. > Vogt-Koelln-Strasse 30, rm. 107 C
e-mail: bontchev@fbihh.informatik.uni-hamburg.de    D-2000 Hamburg 54, Germany
From: grady@netcom.com (1016/2EF221)
Subject: Re: The [secret] source of that announcement
Organization: capriccioso
X-Newsreader: TIN [version 1.1 PL6]
Lines: 35
I guess the cryptowranglers read this group too.  But of
course I knew that because it is so easy to do.  There is
not a single doubt in my mind that every byte that passes
every significant gateway or 'bone is captured for the
colligation of data about __________?  (Maybe your name is here).
Maybe we should start a newsgroup for the distribution of encrypted
posts intended of members of affinity groups with a shared private
key.  For example at the coming up Cypherpunks meeting, a private
key corresponding to that particular meeting could be passed out
by a moderator.  Minutes, followup comments to other participants,
and so on could be posted to the alt.encrypted group for the use
of the people who attended. Communiques intended by the group for
non-attendees could of course just be signed using the private key
but otherwises not encrypted.
Starting a alt.encrypted newsgroup rather than just maintaining
mailing lists is better for several reasons.  First, it would be
easier to archive for people who might join a group "late" and
who might like to easily read earlier posts; second, traffic analysis
to know exactly to whom an affinity message is directed would be foiled;
three, a newsgroup is much more public and would serve to publicize
available privacy measures on the internet.
And it would be fun to accumulate a secret keyring full of such
keys -- it beats giving out t-shirts as a door prize.
We could send a copy of alt.encrypted directly to Judge William
Sessions or Admiral Studeman to save them the time of having it
collected for them.
--
grady@netcom.com  2EF221 / 15 E2 AD D3 D1 C6 F3 FC  58 AC F7 3D 4F 01 1E 2F
From: ptrei@bistromath.mitre.org (Peter Trei)
Subject: Re: Screw the people, crypto is for hard-core hackers & spooks only
Nntp-Posting-Host: bistromath.mitre.org
Organization: The MITRE Corporation
Lines: 41
In article <strnlghtC5t4o3.K5p@netcom.com> strnlght@netcom.com (David Sternlight) writes:
>Actually the govrnment is telling you that if you want to use their
>"product" the manufacturer (actually better yet, some "trusted" pair
>of escrow agencies) has to have the key.
>
>Most of us already are in this situation--our car makers have keys to our
>cars (or can get them quickly from the VIN  number), and I have no doubt
>that if presented with a court order, they'd surrender copies to the
>government.
>Chances are that many locksmiths have the code numbers for house locks
>they've installed, and in an emergency can cut keys; thus they'd also
>provide such keys to the government pursuant to a court order.
Of course, nothing prevents you from buying a new lock with cash
and installing it yourself. Even modifying the core to match some
arbitrary key is not difficult to do at home. I once knew someone who
had fixed his locks in this way - his house, office and cars all took
the same key (which he took GOOD care of :-)
>The state has no difficulty gaining access to your safe deposit box if they
>have a court order.
>Bad analogy.
Very bad (yours, that is). Have you ever had a safety deposit box?
They work on a two-key system. The bank clerk has one, and you have
the other (they are different keys). The bank does NOT keep a copy of
your key. If you lose it, they have to drill out the lock, and replace
the door. This is a time consuming and expensive process (which they
will be happy to charge to your account :-).
This process is exactly analogous to having a private key which
is NOT in a escrow system, and the state having to crack your cipher
to get the data.
Please do not use false analogies.
Peter Trei
ptrei@mitre.org
From: langford@gems.vcu.edu
Subject: Re: Organized Lobbying for Cryptography
Organization: Medical College of Virginia
Lines: 29
In article <1993Apr20.213718.23129@husc3.harvard.edu>, kubo@zariski.harvard.edu (Tal Kubo) writes:
> Having mentioned the possible dangers of unwelcome political associations,
> I would be remiss not to suggest something in the opposite direction:
> gathering the support of the NRA by emphasizing the RKBA side of the
> issue as well as the First-Amendment side.
>
> Tal  kubo@math.harvard.edu
>
>
Hmmm, this gave me an interesting idea.  How about this argument:
1)  Second Amendment gives us the right to keep and bear arms.
2)  Strong cryptography is "arms", according to the U.S. government (that's
why it's so hard to export).
Therefore, we have a constituitional right to strong cryptography!
Q.E.D.
However, it's likely to be as hard or harder to exercise this right as it
is getting to exercise the other rights that the government is slowly
restricting.  Maybe the NRA _would_ be the best existing organization?
(Although I think a new one might be better, but perhaps would take too long
to start up.  I would certainly join.)
--
| From the electronic desk of Bob Langford          Health Sciences Computing
| 804-786-9843   (fax: 804-786-9807)         Virginia Commonwealth University
| e-mail:  langford@gems.vcu.edu     [or]     langford@vcuvax  (for BITNET)
From: steve-b@access.digex.com (Steve Brinich)
Subject: Re: Off the shelf cheap DES keyseach machine (Was: Re: Corporate acceptance of the wiretap chip)
Organization: Express Access Online Communications, Greenbelt, MD USA
Lines: 17
NNTP-Posting-Host: access.digex.net
> > :Thousands?  Tens of thousands?  Do some arithmetic, please...  Skipjack
> > :has 2^80 possible keys.
> >
> > We don't yet know if all 80 bits count.
>
> That doesn't worry me at all; they're not going to cheat at something
>they can get caught at.  And key size is one of the things that can be
>verified externally.  Feed lots of random key/input pairs into the
>chip, then see what happens to the output....
If the device is designed to use the key that's registered with the Feds,
I don't see how you -can- feed it a different key.  If the user can change
the key to any of the 2^80 possibilities, the main reason for regarding
this proposal as unacceptable disappears.
From: tom@ssd.csd.harris.com (Tom Horsley)
Subject: Re: Off the shelf cheap DES keyseach machine (Was: Re: Corporate acceptance of the wiretap chip)
Organization: Harris Computer Systems Division
Lines: 27
<1993Apr20.150531.2059@magnus.acs.ohio-state.edu>
<1993Apr20.192105.11751@ulysses.att.com> <C5sy1z.4tD@demon.co.uk>
<1993Apr21.132318.16981@ulysses.att.com>
NNTP-Posting-Host: amber.ssd.csd.harris.com
In-reply-to: smb@research.att.com's message of Wed, 21 Apr 1993 13:23:18 GMT
>I don't like the unit key generation process any better than you do.
>However -- S1 and S2 are supposed to be under control of the same
>escrow agents.  If they can't be trusted to keep the seed values secure,
>they can't be trusted to keep the half-keys secure.
I hope there is something I don't understand about this system, but can
someone tell me how these chips are going to be manufactured while maintaining
each half key under total control of the separate escrow agencies? Don't
both halfs of the key have to come together (in some form) at the time
the chip is constructed?
Or is it built like a fusable prom, with the chip being sent to the 1st
escrow agency to program its 1/2 key, then the 2nd agency to program its
1/2 key (but who invents the safeguards that prevent the 2nd agency from
reading the information already programmed by the 1st)?
This isn't intended to be a flame or anything, I am just really curious
how to manufacture these things while still maintaining the key escrow
security without simply saying "trust the manufacturer, they won't look".
--
======================================================================
domain: tahorsley@csd.harris.com       USMail: Tom Horsley
uucp: ...!uunet!hcx1!tahorsley               511 Kingbird Circle
Delray Beach, FL  33444
+==== Censorship is the only form of Obscenity ======================+
|     (Wait, I forgot government tobacco subsidies...)               |
+====================================================================+
From: angel@Foghorn_Leghorn.coe.northeastern.edu (Kirill Shklovsky)
Subject: Re: Once tapped, your code is no good any more.
Organization: Northeastern University
Distribution: na
Lines: 36
In article <1993Apr21.204036.13723@rick.dgbt.doc.ca> jhan@debra.dgbt.doc.ca (Jerry Han) writes:
>As one of the happily sleeping people, I would just like to ask this->
>aren't people just slightly overreacting to this?  Or are we all of a
>sudden going to draw parallels to Nazi Germany and Communist Russia?
>
>The point of the matter is that; yes this is a serious problem.  But it is
>not the end of the world.  Guess what?  We're doing something now you
>can't do in a Communist country or Nazi Germany.  We're complaining about
>it, (or rather, you're complaining about it) and nobody is shooting at us.
>
>(Or, rather, if they're shooting at me, they have real bad aim.  (:-) )
>
>GUESS WHAT PEOPLE?  You live in one of the few countries in the world
>where a person can complain without getting shot at.
>
>People are always complaining that somebody did this wrong, or somebody
>did that wrong, or whatever.  Sit down and figure out two things:
>
>1)  What have they done right?
>2)  How much worse can it get?
>
>And you'll find that you and I, are pretty damn lucky.
>
>So let's talk about it, get some action going, decide what's going on.
>But let's not overreact!
>
Us having the liberties to talk about this doesn't make the problem go
away.  It doesn't make it right.  Rather the opposite, if we do not do
anything about it, you can bet it's going to get worse.
*             Angel@foghorn_leghorn.coe.northeastern.edu
*   * *     *   BTW: These are my opinions, and not that of any other entity
- * * *   *   * * ------------------------------------------------------------*
*     * *               My god, its full of stars! - Dave
*        I don't know about you, but we've got company!  - Epidemic
From: sphughes@sfsuvax1.sfsu.edu (Shaun P. Hughes)
Subject: Re: Organized Lobbying for Cryptography
Organization: San Francisco State University
Distribution: inet
Lines: 27
In article <1r3jgbINN35i@eli.CS.YALE.EDU> jgfoot@minerva.cis.yale.edu writes:
>Tarl Neustaedter (tarl@coyoacan.sw.stratus.com) wrote:
>
>: It means that the EFF's public stance is complicated with issues irrelevant
>: to the encryption issue per se. There may well be people who care about
>: the encryption issue who don't care to associate themselves with the
>: network erotica issue (or may even disagree with the EFF's position).
>
>Perhaps these encryption-only types would defend the digitized porn if it
>was posted encrypted?
>
>These issues are not as seperable as you maintain.
>
Now why would anyone "post" anything encrypted? Encryption is only of
use between persons who know how to decrypt the data.
And why should I care what other people look at?
What does concern me is the continued erosion of my constitutional
rights. ( Amendments I, II, IV, and V to note a few. )
--
Shaun P. Hughes                          "Facts are Stupid Things."
sphughes@sfsuvax1.sfsu.edu                Ronald Reagan
Republican National
Finger for PGP 2.2 Public Key             Convention 1988
From: jgfoot@minerva.cis.yale.edu (Josh A. Goldfoot)
Subject: Re: Organized Lobbying for Cryptography
Organization: Yale University
Lines: 21
Distribution: inet
Reply-To: jgfoot@minerva.cis.yale.edu
NNTP-Posting-Host: minerva.cis.yale.edu
X-Newsreader: TIN [version 1.1 Minerva PL9]
Shaun P. Hughes (sphughes@sfsuvax1.sfsu.edu) wrote:
: In article <1r3jgbINN35i@eli.CS.YALE.EDU> jgfoot@minerva.cis.yale.edu writes:
[deletion]
: >Perhaps these encryption-only types would defend the digitized porn if it
: >was posted encrypted?
: >
: >These issues are not as seperable as you maintain.
: >
: Now why would anyone "post" anything encrypted? Encryption is only of
: use between persons who know how to decrypt the data.
: And why should I care what other people look at?
I was responding to another person (Tarl Neustaedter) who held that the
EFF wasn't the best organization to fight for crytography rights since the
EFF also supports the right to distribute pornography over the internet,
something some Crypto people might object to. In other words, he's
implying that there are people who will protect any speech, just  as long
as it is encrypted.
From: steve-b@access.digex.com (Steve Brinich)
Subject: Re: Once tapped, your code is no good any more.
Organization: Express Access Online Communications, Greenbelt, MD USA
Lines: 5
Distribution: na
NNTP-Posting-Host: access.digex.net
Agreed.  This is like the Bay of Pigs fiasco (planned by the Eisenhower
Administration but given the final green light by Kennedy).
To be sure, hen it all went down, Kennedy was at least man enough to take
full responsibility, which is not what I expect from Slick Willie Clinton....
From: arc@leland.Stanford.EDU (Andrew Richard Conway)
Subject: Re: Once tapped, your code is no good any more.
Organization: Society for the conservation of momentum
Distribution: na
Lines: 65
In article <1993Apr21.204036.13723@rick.dgbt.doc.ca> jhan@debra.dgbt.doc.ca (Jerry Han) writes:
>In article <bontchev.735404289@fbihh>
>
>As one of the happily sleeping people, I would just like to ask this->
>aren't people just slightly overreacting to this?  Or are we all of a
>sudden going to draw parallels to Nazi Germany and Communist Russia?
Yes. Reasonable parallels. (though I don't think Russia ever claimed to be
Communist)
>The point of the matter is that; yes this is a serious problem.  But it is
>not the end of the world.  Guess what?  We're doing something now you
>can't do in a Communist country or Nazi Germany.  We're complaining about
I must protest your "...in a Communist country". How do you know?
There haven't been any, and are unlikely to ever be any. In some Socialist
dictatorships, you can't, whilst in some socialist democracies
(such as France or Australia)
you can. Of course, some people may disagree about France & Australia being
socialist...
>it, (or rather, you're complaining about it) and nobody is shooting at us.
Yet.
>(Or, rather, if they're shooting at me, they have real bad aim.  (:-) )
>
>GUESS WHAT PEOPLE?  You live in one of the few countries in the world
>where a person can complain without getting shot at.
In some circumstances. I was at a public meeting last night (in the USA), where
a protester, who was very nice and calm, and just said before the
speaker started to beware of his opinions, was forced out of the meeting by
two armed policemen.
There are a lot of things that one cannot do in the USA. You may not
notice them, but as an Australian visitor, I notice them.
>People are always complaining that somebody did this wrong, or somebody
>did that wrong, or whatever.  Sit down and figure out two things:
>
>1)  What have they done right?
>2)  How much worse can it get?
>
>And you'll find that you and I, are pretty damn lucky.
Yes, we are lucky at the moment. I hope that is still true in
a few years time. Because it didn't just happen...it required concious
effort.
>So let's talk about it, get some action going, decide what's going on.
>But let's not overreact!
Of course don't over react --- but don't under react.
Andrew.
Disclaimer: All my opinions are my own, and do not represent the society
for the conservation of momentum or any other group. I hope I don't lose
my student Visa as a result of these opinions..
--
-----------------------------------------------------------------
Andrew Conway    arc@leland.stanford.edu  Phone: USA 415 497 1094
From: ebrandt@jarthur.claremont.edu (Eli Brandt)
Subject: Re: Off the shelf cheap DES keyseach machine (Was: Re: Corporate acceptance of the wiretap chip)
Organization: Harvey Mudd College, Claremont, CA 91711
Lines: 15
In article <1993Apr21.132318.16981@ulysses.att.com> smb@research.att.com (Steven Bellovin) writes:
>Remember that they've promised to let a committee of outside experts see
>the cryptosystem design.
I hope there are some silicon jocks on the committee who can follow
the algorithm through to hardware.  While I doubt the NSA would pull
any monkey business on this point -- they have to expect that the
chip will be reverse-engineered sooner or later -- it's an obvious
opportunity to introduce additional holes.
>		--Steve Bellovin
PGP 2 key by finger or e-mail
Eli   ebrandt@jarthur.claremont.edu
From: george@tessi.com (George Mitchell)
Subject: Re: Organized Lobbying for Cryptography
Organization: Test Systems Strategies, Inc., Beaverton, Oregon
Lines: 25
langford@gems.vcu.edu writes:
>In article <1993Apr20.213718.23129@husc3.harvard.edu>, kubo@zariski.harvard.edu (Tal Kubo) writes:
>> Having mentioned the possible dangers of unwelcome political associations,
>> I would be remiss not to suggest something in the opposite direction:
>> gathering the support of the NRA by emphasizing the RKBA side of the
>> issue as well as the First-Amendment side.
>Hmmm, this gave me an interesting idea.  How about this argument:
>1)  Second Amendment gives us the right to keep and bear arms.
>2)  Strong cryptography is "arms", according to the U.S. government (that's
>    why it's so hard to export).
>Therefore, we have a constituitional right to strong cryptography!
>Q.E.D.
>[. . .]  Maybe the NRA _would_ be the best existing organization?
I think a new organization would be a much better idea, as the NRA
carries as much undesireable baggage for me as the EFF and CPSR do
for others.
Are any hot-shot, reputable organizers reading this message?  If an
effective group comes into existence, it can count on me signing up.
-- George Mitchell (george@tessi.com)
From: A. Charles Gross <acg@eff.org>
Subject: I have seen the lobby, and it is us
X-Xxmessage-Id: <A7FAF1313A01AC87@l-b-johnson.eff.org>
X-Xxdate: Wed, 21 Apr 93 17:40:17 GMT
Nntp-Posting-Host: l-b-johnson.eff.org
Organization: Electronic Frontier Foundation
X-Useragent: Nuntius v1.1.1d17
Lines: 22
In article <1993Apr21.113152.395@gems.vcu.edu> , langford@gems.vcu.edu
writes:
>However, it's likely to be as hard or harder to exercise this right as it
>is getting to exercise the other rights that the government is slowly
>restricting.  Maybe the NRA _would_ be the best existing organization?
>(Although I think a new one might be better, but perhaps would take too
long
>to start up.  I would certainly join.)
The NRA is successful because (among a number of things), on the drop of
a hat, they can get a congresspersons office flooded with postcards,
faxes and phone calls.  Certainly, with our way-cool Internet powers of
organization, we can act in the same way, if such action is appropriate.
As long as we are kept informed of events, anyone on this bboard can make
a call to action.  Hopefully, we're a strong enough community to act on
those calls.  I realize this is a little optomistic, and I'm glad EFF is
working in the loop on these issues, but don't underestimate the
potential of the net for political action.
Adam
* I speak for myself
From: andyl@harlqn.co.uk (Andy Latto)
Subject: Re: Off the shelf cheap DES keyseach machine (Was: Re: Corporate acceptance of the wiretap chip)
In-Reply-To: smb@research.att.com's message of Wed, 21 Apr 1993 13:23:18 GMT
Nntp-Posting-Host: epcot.harlequin.com
Organization: Harlequin Limited, Cambridge, England
<1993Apr20.150531.2059@magnus.acs.ohio-state.edu>
<1993Apr20.192105.11751@ulysses.att.com> <C5sy1z.4tD@demon.co.uk>
<1993Apr21.132318.16981@ulysses.att.com>
Lines: 42
In article <1993Apr21.132318.16981@ulysses.att.com> smb@research.att.com (Steven Bellovin) writes:
In article <C5sy1z.4tD@demon.co.uk>, Graham Toal <gtoal@gtoal.com> writes:
> In article <1993Apr20.192105.11751@ulysses.att.com> smb@research.att.com (Steven Bellovin) writes:
> :Thousands?  Tens of thousands?  Do some arithmetic, please...  Skipjack
> :has 2^80 possible keys.
>
> We don't yet know if all 80 bits count.
That doesn't worry me at all; they're not going to cheat at something
they can get caught at.  And key size is one of the things that can be
verified externally.  Feed lots of random key/input pairs into the
chip, then try flipping random key bits, and see what happens to the
output.  We already know what *should* happen -- about half the output
bits should vary, on average, from a 1-bit key change or input change.
If they were out to build a weak cryptosystem, it might be the case that
some of the bits are much less powerful than others, in the sense that
they only enter into the encryption very late in the game.  By contrast,
DES was designed to use each key bit as early as possible; the 50% output
change rate appears as early as round 5.  Again, though, I don't think
NSA is going to cheat that crudely; they're likely to get caught.
Consider a cryptosytem that starts out by XORing bits 23 and 47, and
not using either of these bits except through this XOR. This system
makes early use of every bit. but an exhaustive key search would now
only have 2^79 keys to search. Your test by varying single key bits
wouldn't turn up anything interesting.
Remember that they've promised to let a committee of outside experts see
the cryptosystem design.  If you assume something DES-like, a biased
subkey generation schedule will stick out like a sore thumb.
The algorithm I suggest above would stick out like a sore thumb, but
I'm sure I could design a system with a more subtle key redundancy
which was well-hidden, but would still make an exhaustive key search
take far less than 2^80 encryptions. I don't believe your claim that
the real keysize can be verified externally.
Andy Latto
andyl@harlequin.com
From: caronni@nessie.cs.id.ethz.ch (Germano Caronni)
Subject: Re: Do we need the clipper for cheap security?
Organization: Swiss Federal Institute of Technology (ETH), Zurich, CH
Lines: 19
In article <9304201003.AA05465@pizzabox.demon.co.uk> gtoal@gtoal.com (Graham Toal) writes:
>Can someone tell me if hardware compression is or is not needed to run
>digital speech down 14.4K?  I think it is; I've heard it's not.  Lets
>say 8 bit samples.  Would *raw* data at the corresponding sampling rate
>be usable?  If not, how fancy does the compression need to be?
As far as I know ISDN (call it Swissnet here, and it's being plugged in) it's
8 bit 8000Hz (gives you one channel of 64kBit/sec) I guess you should not go
below a sampling rate of 6000 Hz if you want to have same quality as on an
analog-line. Anybody knows compression-algorithms & -factors for voice ?
Greetings,
Germano Caronni
--
Instruments register only through things they're designed to register.
Space still contains infinite unknowns.
PGP-Key-ID:341027
Germano Caronni caronni@nessie.cs.id.ethz.ch   FD560CCF586F3DA747EA3C94DD01720F
From: Tony Lezard <tony@mantis.co.uk>
Subject: Re: text of White House announcement and Q&As on clipper chip encryp
Distribution: world
Organization: Mantis Consultants, Cambridge. UK.
Lines: 13
gtoal@gtoal.com (Graham Toal) writes:
> Whatever happens though, the effect of this new chip will be to make private
> crypto stand out like a sore thumb.
ONLY IF this chip catches on. Which means alternatives have to be
developed. Which will only happen if Clipper is discredited.
--
Tony Lezard IS tony@mantis.co.uk | PGP 2.2 public key available from key
OR tony%mantis.co.uk@uknet.ac.uk | servers such as pgp-public-keys@demon.co.uk
OR EVEN      arl10@phx.cam.ac.uk | 172045 / 3C85783F 09BBEA0C B86CF9C6 7A5FA172
From: mathew <mathew@mantis.co.uk>
Subject: Re: text of White House announcement and Q&As on clipper chip encryption
Organization: Mantis Consultants, Cambridge. UK.
X-Newsreader: rusnews v1.02
Lines: 9
bena@dec05.cs.monash.edu.au (Ben Aveling) writes:
> Don't forget, you are in the country that wouldn't let the Russians
> buy Apple II's because of security concerns.
That's nothing.  They wouldn't let the British buy Inmos Transputer systems
because of security concerns.  And we designed the damn things!
mathew
From: psionic@wam.umd.edu (Haywood J. Blowme)
Subject: new encryption
Nntp-Posting-Host: rac3.wam.umd.edu
Organization: University of Maryland, College Park
Lines: 120
As promised, I spoke today with the company mentioned in a Washington
Times article about the Clipper chip announcement. The name of the company
is Secure Communicatiions Technology (Information will be given at the end
of this message on how to contact them).
Basically they are disturbed about the announcement for many reasons that
we are. More specifically however, Mr. Bryen of Secure Communications
brought to light many points that might interest most of the readers.
His belief is that AT&T was made known of the clipper well before the
rest of the industry. This is for several reasons, several of which are:
- A company of AT&T's size could never be able to make a decision to use
the new chip on the SAME DAY it was announced.
- Months ago they proposed using their own chip for AT&T's secure telephone
devices. AT&T basically blew them off as being not interested at all.
This stuck them as strange, until now...
Also I spoke with Art Melnick, their cryptographer, he expressed several
concerns over the new Clipper Chip:
- The obvious backdoor will be able to let many people decrypt the code.
- Once the key is released to authorities the security of the crypto
system is lost forever. These keys can end up in the hands of any agency
of the government.
- The fact that the escrowed keys never change means that the algorithm
is vulnerable over time to an attacker.
- The classified algorithm may hide another backdoor. But he feels that
it is probably to keep people from forging fake serial numbers, or
changing the keys themselves.
- Additionally he feels that the NSA has probably spent enough time and
money in working on a way to keep this chip from being reversed
engineered, that he feels that reverse engineering it will be very
difficult to do. He feels that they have developed a suitable technique
to protect the chip from this attack. Also he feels that the chip is
hardware encoded with the algorithm and not microcoded onto the chip.
Additonally I spoke with Mr. Melnick about their algorithm. He couldn't tell
me much about their new agorithm because it hasn't been patented yet.
However he told me a little:
- The algorithm will be released for public review after patents have been
granted for it. This is so the crypto community can see that it is
secure.
- The algorithm is called NEA for New Encryption Algorithm.
The details were sketchy because now it is held as a trade secret
until the patent was issued, but I was told that it will incorporate
the following:
- It will have fast encryption of data (Exact specs not given, but
Mr. Melnick stated "Much faster than what an RS-232 can put out.")
- It is a symmetric cipher, just like IDEA and DES.
- It will use 64 bit data blocks for encryption (like DES and IDEA).
- The key length was not given to me, but Mr. Melnick states that
it is _adujustable_ and is "More than adequate for security."
- The algorithm is written in C and Assembler in software form, and
can be ported to many platforms (Unlike the the Clipper Chip which
is hardware ONLY and cannot be made into software) This I
consider a definite plus for the NEA for widespread use.
- The algorithm will accomodate public key distribution techniques
such as RSA or Diffie-Hellman. This will also be supported in the
hardware chip.
- Right now the projected cost of the NEA chip will be about 10 dollars
for each!! (Clipper will run 25 each chip [that is if it is produced
enough, which probably won't happen]).
- They currently sell a program called C-COM that uses the algorithm
and a special streaming protocol that does not divide the encrypted
data into "blocks." This could prevent plaintext attacks if you know
what the block header is. This program operates at all supported
RS-232 speeds and uses the software implementation of the algorithm.
- Most importantly: IT DOES NOT HAVE A BACKDOOR!!
Right now the company is afraid that the new clipper chip will put them out
of business. This is a very real possibility. So they really need help in
stopping the clipper chip from becoming a standard. If you want to contact
them, they can be reached at..
Secure Communications Technology
8700 Georgia Ave. Suite 302
Silver Spring, MD
(301) 588-2200
I talked to Mr. Bryen who represents the company. He can answer any
questions you have.
Any factual errors occurring in this write up are my own and I apologize for
them ahead of time.
=============================================================================
///    | psionic@wam.umd.edu | Fight the WIRETAP CHIP!! Ask me how!
__  /// C=  | -Craig H. Rowland-  |
\\\/// Amiga| PGP Key Available   | "Those who would give up liberty for
\///  1200 | by request.         |  security deserve neither."
=============================================================================
A
From: neuhaus@vier.informatik.uni-kl.de (Stephan Neuhaus (HiWi Mattern))
Subject: Re: Do we need the clipper for cheap security?
Nntp-Posting-Host: vier.informatik.uni-kl.de
Organization: University of Kaiserslautern, Germany
Lines: 39
gtoal@gtoal.com (Graham Toal) writes:
>Can someone tell me if hardware compression is or is not needed to run
>digital speech down 14.4K?  I think it is; I've heard it's not.  Lets
>say 8 bit samples.  Would *raw* data at the corresponding sampling rate
>be usable?  If not, how fancy does the compression need to be?
Note: I am *not* a cable freak, so I might have completely
misunderstood what you said.  Also, my math is frequently noted for
being wrong, so you'll better check the calculations yourself.
I assume that 14.4K means 14.4K Bits.  So if we assume one start and
one stopbit, and no protocol overhead, the effective number of bytes
per second is 1.44K.
Let's also assume that you do not want to transmit your speech in
stereo, so that you can send 1,440 samples/sec.  This corresponds to a
Nyquist frequency of 720 Hz, which should be too low, especially if
you think about the 8-bit low quality sound.  Furthermore, your D/A
converter will probably not present you with a signal that has been
cut off at 720 Hz, but will instead alias in all the higher
frequencies.  (Although you can definitely build a filter to overcome
that problem.)
On the other hand, speech should be easily compressible.  For example,
you could form power spectra, or you could simply band-pass filter and
then linearize the fourier transforms.  It won't be CD quality sound,
but it'll be discernible.  The power spectrum method is very good in
that respect.  I have once programmed such a software compressor, and
compression rates of 90% with relative errors due to linearization of
less than 5% were common.  Although I must say that these were musical
sounds, not speech.
Have fun.
--
Stephan <neuhaus@informatik.uni-kl.de>
sig closed for inventory.  Please leave your pickaxe outside.
PGP 2.2 public key available on request.  Note the expiration date.
From: m.t.palmer@larc.nasa.gov (Michael T. Palmer)
Subject: Re: Once tapped, your code is no good any more.
Organization: NASA Langley Research Center, Hampton, VA
Lines: 52
Distribution: inet
NNTP-Posting-Host: oldtown.larc.nasa.gov
In article <1993Apr21.150815.6657@chpc.org> rboudrie@chpc.org (Rob Boudrie) writes:
>In article <C5so84.Hxv@demon.co.uk> Graham Toal <gtoal@gtoal.com> writes:
>>In article <2073@rwing.UUCP> pat@rwing.UUCP (Pat Myrto) writes:
>>:If the Clinton Clipper is so very good, why not make its algrithm public
>>:so many people can exchange ideas and examine it, rather than a few
>>:isolated 'respected experts' (respected by whom?  for what?  Perhaps a
>
>One more time...
>
>    If they released the algorithm, it would be possible for someone
>    to come up with an implementation which was identical, but
>    lacking an escrowed key.
>
>    Note that the press announcement mentioned that the algorithm was
>    being kept secret for security of the key escrow system.  In this
>    case security means "an escrowed key for EVERY clipper chip".
>
>
>    Assuming you believed all that is said about the effective of
>    the algorithm, and the escrow system, which would you buy :
>
>     (a)  Chip from firm A with the escrowed key
>     (b)  Second source chip from reputable firm B with no key
>          in government escrow.
>
>    There would obviously be powerful economic incentives for a second
>    source, non escrowed, vendor.
But what about second sources for pin-compatible non-Clipper algorithm
chips that also have escrowed keys?  If a "reputable firm" produces a
chip (with escrowed key) that is a pop-in replacement for the Clipper
chip in my phone, and uses an algorithm that is widely known and evaluated
and "trusted," then what's the problem?
The Clipper is going to be reverse engineered anyway by any organization
with sufficient resources (can you say "billions of cocaine dollars?") so
those drug dealers they're so worried about will be slipping through the
cracks.  We law-abiding (non-incredibly-wealthy) citizens, naturally, will
not have this recourse.  But claiming that the algorithm can't be
released to prevent people from using non-key-escrowed chips is plain
deceitful... analysis of the chip output will provide information on
the necessary headers and whatnot, so the "bad guys" could build chips
using a *different* algorithm and still not escrow their keys.
Or, they could just buy bunches of cheap phones at K-mart every week,
and play Swap-the-Clipper-Chip with their cellular phone every day.
Michael T. Palmer         |  "A man is crazy who writes a secret in any
m.t.palmer@larc.nasa.gov  |   other way than one which will conceal it
RIPEM key on server       |   from the vulgar." - Roger Bacon, 1220-1292
From: rboudrie@chpc.org (Rob Boudrie)
Subject: Re: How to detect use of an illegal cipher?
Organization: Center For High Perf. Computing of WPI; Marlboro Ma
Lines: 25
>As for my impressions of the whole scheme It seems that instead of trying to
>ban strong crypto, they are trying to co-opt it. Their contention that they
>need to keep the algorythm secret to protect the security of the key
>registration suggests possible inherent weakness to the algorythm. More likely
>is that they dont want anyone constructing black market devices which dont
>have the keys registered. Anyone else notice that in their Q&A session, they
Preventing black market chips w/non-escrowed keys IS exactly what they
mean by protecting the security of the key escrow system.  There are
two parts to the security of such a system:
(a) Preventing decruption by unauthorized personel
(b) Assuring that the gummit can always decrypt clipper
traffic when it authorizes itself to do so.
Of course, the ministry of propoganda will do a lot of tallking about
(a) and very little about (b).
rob boudrie
rboudrie@chpc.org
ps: Anyone care to guess what encryption scheme the gov't is using on
its newly formed database of anarch-cryptists who oppose this entire
lunacy?
Subject: Re: Screw the people, crypto is for hard-core hackers & spooks only
From: a_rubin@dsg4.dse.beckman.com (Arthur Rubin)
<1r0ausINNi01@senator-bedfellow.MIT.EDU> <1993Apr20.145338.14804@shearson.com> <1r47l1INN8gq@senator-bedfellow.MIT.EDU>
Organization: Beckman Instruments, Inc.
Nntp-Posting-Host: dsg4.dse.beckman.com
Lines: 24
In <1r47l1INN8gq@senator-bedfellow.MIT.EDU> jfc@athena.mit.edu (John F Carr) writes:
>In most cases information you come by properly is yours to use as you wish,
>but there are certainly exceptions.  If you write a paper which includes
>sufficiently detailed information on how to build a nuclear weapon, it is
>classified.  As I understand the law, nuclear weapons design is
>_automatically_ classified even if you do the work yourself.  I believe you
>are then not allowed to read your own paper.
This has now been thrown out by the courts.  (The "Progressive" case.)
>A less serious example: if you tell drivers about a speed trap they are
>about to run into, you can be fined, even though you might argue that you
>broke no law when you discovered the location of the policeman.  The charge
>is interfering with a police officer, which is quite similar what you would
>be doing by reverse engineering the Clipper chip.
This is outright illegal.  It DOES violate the first amendment.  If you
would, give a case in which your "speed trap" example has been upheld by
the courts.
--
Arthur L. Rubin: a_rubin@dsg4.dse.beckman.com (work) Beckman Instruments/Brea
216-5888@mcimail.com 70707.453@compuserve.com arthur@pnet01.cts.com (personal)
My opinions are my own, and do not represent those of my employer.
Subject: Re: Once tapped, your code is no good any more.
From: a_rubin@dsg4.dse.beckman.com (Arthur Rubin)
Distribution: na
Organization: Beckman Instruments, Inc.
Nntp-Posting-Host: dsg4.dse.beckman.com
Lines: 33
In <strnlghtC5uIJ4.76t@netcom.com> strnlght@netcom.com (David Sternlight) writes:
>In article <ELEE9SF.93Apr21095141@menudo.menudo.UH.EDU>
>elee9sf@menudo.menudo.UH.EDU (Karl Barrus) writes:
>>
>>Would you trust a black-box from the NSA versus an "open system" from
>>elsewhere?
>Absolutely, if I were assured by someone I trusted that the black box was
>more secure. I have nothing to conceal from the government, but I would like
>to be sure that any Russian, Japanese, French, or other competitors for my
>services can't read my traffic. I'd like to be sure that competitive bid
>information was safe from commercial competitors and foreign governments
>which would aid them.
>I believe the NSA has identical motivations with respect to my activities.
>The President and many other senior government officials have made it very
>clear that they share these motivations. Thus I'd trust them on the
>"coincidence of interests" argument as well as on a basic trust in their
>professionalism and a high confidence in their skills.
>David
>--
>David Sternlight         Great care has been taken to ensure the accuracy of
>                         our information, errors and omissions excepted.
Nothing but errors and omissions here!
--
Arthur L. Rubin: a_rubin@dsg4.dse.beckman.com (work) Beckman Instruments/Brea
216-5888@mcimail.com 70707.453@compuserve.com arthur@pnet01.cts.com (personal)
My opinions are my own, and do not represent those of my employer.
From: mbeckman@mbeckman.mbeckman.com (Mel Beckman)
Subject: Re: text of White House announcement and Q&As on clipper chip encryption
Organization: Beckman Software Engineering
Reply-To: mbeckman@mbeckman.com
Distribution: na,world
X-Mailer: uAccess LITE - Macintosh Release: 1.5v5
Lines: 47
In article <1993Apr17.032022.14021@clarinet.com> (sci.crypt,alt.security,comp.org.eff.talk,comp.security.misc,comp.org.acm,comp.org.ieee), brad@clarinet.com (Brad Templeton) writes:
> Let's assume, for the moment, that the system really is secure unless
> you get both halves of the encryption key from the two independent
> escrow houses.  Let's say you even trust the escrow houses -- one is
> the ACLU and the other is the EFF.  (And I'm not entirely joking about
> those two names)
The problem with "Let's assume" reasoning is that, taken to the extreme
(and you're close), you arrive at "Let's assume this is perfectly OK."
The assumptions you make are big ones. If the system is really secure, then
why does the government have to keep the algorithm secret?  There are plenty
of encryption algorithms that don't depend upon nondisclosure to be secure,
so why in the world use one that does?  There are reasons, of course, but
I certainly can't think of any honest ones.
Next, you assume we can "trust" the escrow houses. But the last time I checked,
EVERY SINGLE BRANCH OF GOVERNMENT has experienced unauthorized disclosure,
corruption, and even fabrication, of supposedly secure data. The govt is
saying "Yeah, but NOW we're serious, so you can trust us."  Bullcrypt.
And finally, although you didn't state it explicitly, you implicitly assume
that the warrant mechanism in this country is safe and reasonable. The case
in Ventura County of a man shot and killed by officers serving a deliberately
fraudulant warrant tells me that the govt has a long ways to go on this
score.
Remember that all this is to catch the drug dealers, right?  As others
have pointed out, the current proposal will, if deployed, render truly secure
encryption much more expensive and inconvenient than Uncle Sam's brand.
Who will be able to afford, and be sufficiently motivated, to purchase this
expensive, inconvenient higher protection?  Somebody with lots of extra
cash...
The following is more true than ever:
"When [strong] encryption is outlawed, only outlaws will have [strong]
encryption."
________________________________________________________________________
| Mel beckman                  |   Internet: mbeckman@mbeckman.com     |
| Beckman Software Engineering | Compuserve: 75226,2257                |
| Ventura, CA 93003            |  Voice/fax: 805/647-1641 805/647-3125 |
|______________________________|_______________________________________|
"You can observe a lot just by watching."  -Yogi Bera
From: mbeckman@mbeckman.mbeckman.com (Mel Beckman)
Subject: Re: An Open Letter to Mr. Clinton
Organization: Beckman Software Engineering
Reply-To: mbeckman@mbeckman.com
Distribution: world
X-Mailer: uAccess LITE - Macintosh Release: 1.5v5
Lines: 38
In article <strnlghtC5M2Cv.8Hx@netcom.com> (sci.crypt), strnlght@netcom.com (David Sternlight) writes:
> Here's a simple way to convert the Clipper proposal to an unexceptionable
> one: Make it voluntary.
>
> That is--you get high quality secure NSA classified technology if you agree
> to escrow your key. Otherwise you are on your own.
>
David,
As an economist, I'm sure you can see the flaws in this logic. If the (naive)
market is flooded with proprietary, but weak, encryption, then truly strong
encryption will be unable to compete. Suppose the govt had a secret TV broadcast
standard, and then sold TVs below cost. Private industry has a better standard,
but it's not as widespread due to the govt early flooding of the market
with cheap proprietary sets. Even though the industry's technology is better,
the programming is being broadcast to the govt's unduplicatable standard.
Who could compete?
The other flaw, of course, is that making something voluntary today ensures
that it will be voluntary in the future. I went to renew my CA drivers license
last week and was required not only to give my SSN, but to PRODUCE AN SSN
CARD to veryify the number!  Note that a federal law once said that no state
or local govt could ever require the use of SSNs for drivers license registration
(specifically!).
I do not trust the govt that says "trust me on this even though we could
have an arrangement that doesn't require your trust."  Something is big
time fishy. If you look more carefully, you'll see it.
-mel
________________________________________________________________________
| Mel beckman                  |   Internet: mbeckman@mbeckman.com     |
| Beckman Software Engineering | Compuserve: 75226,2257                |
| Ventura, CA 93003            |  Voice/fax: 805/647-1641 805/647-3125 |
|______________________________|_______________________________________|
"You can observe a lot just by watching."  -Yogi Bera
From: rschnapp@metaflow.com (Russ Schnapp)
Subject: Re: Once tapped, your code is no good any more.
Nntp-Posting-Host: habu
Organization: Metaflow Technologies Inc.
Lines: 19
It might be nice to:
1. cut out the ad hominem attacks on Prof. Denning, Mr. Sternlight,
etc.  If you have something objective to say about their views, go
ahead and say it (subject to point 2.).  Personal attacks reflect more
on the attacker more than on the attackee.  Throw light, not heat!
2. restrict the discussion to appropriate newsgroups. I submit that
comp.org.acm and comp.org.ieee are not appropriate for this
discussion.  You have now made subscribers to these newsgroups aware of
the issue.  If they want to know more or participate in the discussion,
they can easily join sci.crypt, comp.security.misc, alt.security, or
comp.org.eff.talk.
--
...Russ Schnapp
Email: netcom!metaflow!rschnapp or rschnapp@Metaflow.com or rschnapp@BIX.com
Metaflow Technologies   Voice: 619/452-6608x230;  FAX: 619/452-0401
La Jolla, California    Unless otw specified, I`m speaking only for myself!
From: mbeckman@mbeckman.mbeckman.com (Mel Beckman)
Subject: Re: Secret algorithm [Re: Clipper Chip and crypto key-escrow]
Organization: Beckman Software Engineering
Reply-To: mbeckman@mbeckman.com
Distribution: world
X-Mailer: uAccess LITE - Macintosh Release: 1.5v5
Lines: 35
In article <1993Apr17.090731.18680@clarinet.com> (sci.crypt), brad@clarinet.com (Brad Templeton) writes:
> Interestingly enough, in designing the escrow, we may want to use some
> rather unusual technology, such as sealed boxes of paper, or
> destructive read memory, rather than typical computer databases, which
> is fun for a database of hundreds of millions of keys.
>
To me, a larger problem is that once disclosed, your keys could be used
to decrypt any previously recorded conversations. I gather that from this
proposal a warrant would be required to get the keys, but not to collect
conversations! Consider the scenario where an agency collects preemptively
all encrypted conversations for certain people likely to be targets (and
not necessarily "legitimate" targets), then arranges for some unrelated
incident that can trigger a warrant:
"Your honor, we know that the suspect has received calls from noted
crime figure Bugsy Butthead [said calls arranged by the agency] and we must
therefore have this warrant to determine whether this suspect, in a
sensitive govt post, is corrupt."
I suppose that it is conceivable that there are session keys involved
somewhere, but that doesn't seem likely; if there are, why wouldn't the
technical overview mention them when it goes to such details as the number
of bits held by each escrow authority?
This scheme is full of holes, and stinks to high heaven.
-mel
________________________________________________________________________
| Mel beckman                  |   Internet: mbeckman@mbeckman.com     |
| Beckman Software Engineering | Compuserve: 75226,2257                |
| Ventura, CA 93003            |  Voice/fax: 805/647-1641 805/647-3125 |
|______________________________|_______________________________________|
"You can observe a lot just by watching."  -Yogi Bera
From: ifarqhar@laurel.ocs.mq.edu.au (Ian Farquhar)
Subject: Re: Screw the people, crypto is for hard-core hackers & spooks only
Organization: Macquarie University, Sydney Australia
Lines: 46
NNTP-Posting-Host: laurel.ocs.mq.edu.au
In article <1r0ausINNi01@senator-bedfellow.MIT.EDU> jfc@athena.mit.edu (John F Carr) writes:
>The chip and algorithm are classified.  If you reverse engineer it and
>tell people, you are likely to go to jail.
I don't find this a credible argument, for two reasons.  One you have
supplied below: unless I care about entering the USA at any time in the
future (eg. the Taiwanese backyard cloners - who BTW have been known to
decap custom silicon and reproduce it on daughterboards when pirating
high-profit arcade machines and the like - who wouldn't care less), I am not
going to care much about US confidentiality, am I?  Only people like the
real me, who does care about travelling to various countries for business
reasons, will sit up and follow laws like this, but I would contend that
we're not the main threat.
I also have grave doubts whether an algorythm widely distributed in silicon
could possibly be called "classified."  It's like handing out military
secrets to the whole world in envelopes marked "don't open me."  I can
imagine several credible defences which could be employed if it came to
a trial.  One would be the stupidity of the government's actions.
>Perhaps some foreign governments or corporations could help us out by
>cracking the system outside the USA.  The US government could probably
>stop importation of clone hardware, but a software implementation
>should be practical.
Amusing thought: could they have employed an algorythm which is infeasable
for a fast software implementation, but which is easy in custom hardware?
In DES, the extensive use of permutation tables (trivial in hardware: you
just swap bus lines), but relatively slow in software have had a big effect
on the speed difference between hardware and software implementations of
that cipher (indeed, I suspect that Lucifer's designers were well aware that
it would be, and approved.)  Certain algorythms (usually parallel search
algorythms) can be very slow in software, yet can fly in custom hardware.
I have no proof of their employment in Clipper -- it is pure conjecture.
However, as a software implementation of this cipher is something that its
designers would have been trying to avoid at all costs, then the inclusion
of such techniques seems credible.
Hmmm... I also wonder what Intergraph thinks about the use of the name
"Clipper" for this device. :)
--
Ian Farquhar                      Phone : + 61 2 805-9400
Office of Computing Services      Fax   : + 61 2 805-7433
Macquarie University  NSW  2109   Also  : + 61 2 805-7420
Australia                         EMail : ifarqhar@laurel.ocs.mq.edu.au.
From: ifarqhar@laurel.ocs.mq.edu.au (Ian Farquhar)
Subject: Re: Screw the people, crypto is for hard-core hackers & spooks only
Organization: Macquarie University, Sydney Australia
Lines: 35
NNTP-Posting-Host: laurel.ocs.mq.edu.au
In article <19930419.155204.305@almaden.ibm.com> ameline@vnet.IBM.COM (Ian Ameline) writes:
>  I also believe that someone will reverse engineer the clipper chip,
>and knowlege of the algorithm will likely be fairly widespread. Any back-
>doors or weaknesses would further discredit the scheme, and help grow
>the market demand for a secure alternative.
I must admit that this point has been running through my mind for most of
the discussion: one the dice are out there, it won't be long before someone
decaps it and, after a bit of work, has full details of the Clipper
algorythm.  This isn't trivial to do, but then again, it is not impossibly
difficult either.  Any half way decent VLSI design student should be able
to take a photograph of a technology s/he is familiar with, and given a
description of the input, output, control and supply lines, figure out
the function of various subsystems on the die.  Indeed, this is not an
uncommon exercise performed during training (because it makes you think
about design decisions made by other designers.
I could speculate that these chips are going to be manufactured using
"tamperproof" carriers (unlikely - such techniques are *very* expensive
and this thing is supposed to be relatively cheap to produce), or that
there will be some legal or legislative framework to prevent publication
of the algorythm (unlikely - please correct me if I am wrong but aren't these
supposed to be sold internationally?).  I suppose that the most likely
reason the algorythm is remaining secret for the moment is that some idiot
bureaucrat, untrammeled by the realities of the situation, decided that
"well, we should keep it a secret because it is supposed to be secret,
isn't it?"
Just some random thoughts...
--
Ian Farquhar                      Phone : + 61 2 805-9400
Office of Computing Services      Fax   : + 61 2 805-7433
Macquarie University  NSW  2109   Also  : + 61 2 805-7420
Australia                         EMail : ifarqhar@laurel.ocs.mq.edu.au.
From: Lyle_Seaman@transarc.com
Subject: Re: Once tapped, your code is no good any more.
Organization: Mail to News Gateway at Wang Labs
Distribution: na
Lines: 47
jhan@debra.dgbt.doc.ca (Jerry Han) writes:
> The point of the matter is that; yes this is a serious problem.  But it is
> not the end of the world.  Guess what?  We're doing something now you
> can't do in a Communist country or Nazi Germany.
Or John Edgar Hoover's USA.
> We're complaining about
> it, (or rather, you're complaining about it) and nobody is shooting at us.
yet.
> GUESS WHAT PEOPLE?  You live in one of the few countries in the world
> where a person can complain without getting shot at.
yet.
> People are always complaining that somebody did this wrong, or somebody
> did that wrong, or whatever.  Sit down and figure out two things:
>
> 1)  What have they done right?
> 2)  How much worse can it get?
>
> And you'll find that you and I, are pretty damn lucky.
so far.
> So let's talk about it, get some action going, decide what's going on.
> But let's not overreact!
What harm is there in overreacting?
This may be the largest single threat to civil liberties yet in my
lifetime.  The US has done some pretty heinous things in the past,
and we haven't yet recovered from all of them.  There certainly seems
to be a historical trend towards less liberty, with occasional
perturbations.
Time to break out the quotes from American political radicals.
Lyle		Transarc		707 Grant Street
412 338 4474	The Gulf Tower		Pittsburgh 15219
There are more instances of the abridgement of the freedom of the
people by the gradual and silent encroachment of those in power,
than by violent and sudden usurpation.          -- James Madison
From: amolitor@nmsu.edu (Andrew Molitor)
Subject: Re: The [secret] source of that announcement
Organization: Department of Mathematical Sciences
Lines: 29
Distribution: inet
NNTP-Posting-Host: moink.nmsu.edu
In article <gradyC5uAMw.BnG@netcom.com> grady@netcom.com (1016/2EF221) writes:
>I guess the cryptowranglers read this group too.  But of
>course I knew that because it is so easy to do.  There is
>not a single doubt in my mind that every byte that passes
>every significant gateway or 'bone is captured for the
>colligation of data about __________?  (Maybe your name is here).
I really like these claims. Where did they come from? We hear,
practically daily, that the NSA monitors, oh, everything. They can
crack anything. They'd never release a cryptosystem they couldn't crack.
Where do people get these fascinating facts? 'The Puzzle Palace'?
If you can get it for a buck, 2nd hand, it must be true, eh? I'm pretty
sure the NSA is supposed to, among many other things, provide high-quality
cryptosystems to a variety of places. I don't recall reading anywhere
reliable that they're supposed to:
1) Monitor my phonecalls.
2) Monitor usenet.
3) Provide only cryptosystems they can easily crack.
4) etc etc.
This is not to say that they *don't*, they might. But you don't
know that they do, and you have no evidence that they do, for almost
all values of you. It follows, therefore, that for most values of 'you',
your claims about the NSA border on paranoia.
Andrew
From: rbrand@usasoc.soc.mil (Raymond S. Brand)
Subject: "Clipper Chip" facts: a request
Organization: is a nice thing...
Lines: 28
Having read the various "Clipper" announcements on the net over the last few
days and a LOT of uninformed speculation about the chip, its uses,
government plots, etc, I have the following questions.
1) What does the "Clipper chip" actually implement? Just the Skipjack
cryptographic algorithm? Or does it also implement a "chip to chip"
communications protocol? If it does implement a communications
protocol, can it be used as just a "crypt chip" also.
2) Where can the chip specifications and spec sheets be obtained?
3) Who may purchase them and under what conditions?
4) Are there restrictions as to how the chip may be used in a system?
5) The security of the algorithm and the encrypted communications does
not appear to require that the "Family key" be a secret. Why is
it a secret? What happens when the "family key" becomes well known?
If it's a secret to make traffic analysis more difficult, does
the "Law enforcement message" contain any random information?
How much and how random is it?
6) Can the chip be programmed to reveal the "Unit key"? The chip "serial
number"? Any of the programming parameters?
-----------------------------------------------------------------------------
Raymond S. Brand					rbrand@usasoc.soc.mil
-----------------------------------------------------------------------------
From: holland@CS.ColoState.EDU (douglas craig holland)
Subject: Re: Once tapped, your code is no good any more.
Distribution: na
Nntp-Posting-Host: beethoven.cs.colostate.edu
Organization: Colorado State University, Computer Science Department
Lines: 40
In article <bontchev.735404289@fbihh> bontchev@fbihh.informatik.uni-hamburg.de writes:
>andersom@spot.Colorado.EDU (Marc Anderson) writes:
>
>> methods.  ``This year's crime bill will have teeth, not bare gums,''
>> Clinton said.  In particular, his administration will place strict
>> controls on data formats and protocols, and require the registration
>> of so-called ``cryptographic keys,'' in the hope of denying drug
>> dealers the ability to communicate in secret.  Clinton said the
>> approach could be used for crackdowns on other forms of underground
>> economic activity, such as ``the deficit-causing tax evaders who
>> live in luxury at the expense of our grandchildren.''
>
>And some people thought that I am exaggerating when claiming that the
>Cripple Chip is just a first step in a totalitarian plot against the
>civil liberties in the USA... It seems that I've even been an optimist
>- the things are happening even faster than I expected.... That's
>another of the dirty tricks they used to apply on us under the
>communist regime - do something secret, THEN tell the people about is
>(after the fact, when nothing can be done any more), and of course,
>explaining them how much better the situation is now...
>
>In my previous messages I wrote that the Americans should wake up and
>fight against the new proposal. Now it seems to me that it is already
>too late - it has already happened, the civil liberties have been
>violated, no, stollen from the American people, while the most part of
>this people has been sleeping happily... :-((( Too sad...
>
I'm definitely going to write my Congressman, and nobody's ever
going to make me respect a law that violates my freedom of speech, and
if the feds try to enforce this law on me, I will protect my freedoms, with
force if it ever comes to that. (Hopefully, it won't)
Doug Holland
--
----------------------------------------------------------------------------
|  Doug Holland                | Anyone who tries to take away my freedom  |
|  holland@cs.colostate.edu    | of speech will have to pry it from my     |
|  PGP key available by E-mail | cold, dead lips!!                         |
From: ebrandt@jarthur.claremont.edu (Eli Brandt)
Subject: Re: Do we need the clipper for cheap security?
Organization: Harvey Mudd College, Claremont, CA 91711
Lines: 56
In article <1r466c$an3@news.intercon.com> amanda@intercon.com (Amanda Walker) writes:
>Agreed.  Remember, I don't even think of Clipper as encryption in any real
>sense--if I did, I'd probably be a lot more annoyed about it.
I agree with this assessment.  Furthermore, its promotion as
providing greater protection than bare voice is quite true, as far
as it goes.  However, the only way for it to fulfill its stated goal
of letting LE wiretap "terrorists and drug dealers" is to restrict
stronger techniques.
Wiretap targets presently use strong encryption, weak encryption, or
(the vast majority) no encryption.  The latter two classes can be
tapped.  With weak encryption in every phone, the no-encryption
class is merged into the weak-encryption class.  Will the
introduction of Clipper cause targets presently enjoying strong
privacy to give up on it?  that is, to rely for privacy on a system
expressly designed to deny it to people like them?  I doubt it.  The
mere introduction of this scheme will give the government *nothing*.
The stated goal of preventing the degradation of wiretapping
capabilities can be fulfilled by restriction of domestic
cryptography, and only by this restriction.  "Clipper" appears to be
no more than a sop, given to the public to mute any complaints.  We
would find this a grossly inadequate tradeoff, but I fear the public
at large will not care.  I hate to even mention gun control, but
most people seem to think that an `assault weapon' (as the NYT uses
the word) is some sort of automatic weapon, .50 caliber maybe.  Who
wants to have such a thing legal?  Well, people know even less about
cryptology; I suspect that strong cryptography could easily be
labeled "too much secrecy for law-abiding citizens to need".
>That's not for Clinton (or anyone under him) to say, though.  Only the
>federal and supreme courts can say anything about the constitutionality.
>Anything the administration or any governmental agency says is opinion at
>best.
What they say is opinion, but what they do is what matters, and will
continue unless overturned.  And the courts are reluctant to annul
law or regulation, going to some length to decide cases on other
grounds.  Furthermore, Congress can get away with quite a bit.  They
could levy a burdensome tax; this would place enforcement in the
hands of the BATF, who as we've seen you really don't want on your
case.  They could invoke the Commerce Clause; this seems most
likely.  This clause will get you anywhere these days.  The 18th was
required because the Supreme Court ruled a prohibitory statute
unconstitutional.  In 1970 Congress prohibited many drugs, with a
textual nod to the Commerce Clause.  The Controlled Substances
Act of 1970 still stands.  I think the government could get away
with it.
>Amanda Walker
PGP 2 key by finger or e-mail
Eli   ebrandt@jarthur.claremont.edu
From: amanda@intercon.com (Amanda Walker)
Subject: Re: Would "clipper" make a good cover for other encryption method?
Organization: InterCon Systems Corporation - Herndon, VA  USA
Lines: 15
Distribution: world
Reply-To: amanda@intercon.com (Amanda Walker)
NNTP-Posting-Host: chaos.intercon.com
X-Newsreader: InterCon TCP/Connect II 1.1
amanda@intercon.com (Amanda Walker) writes:
> I don't get up in arms when
> the government fails to protect the interests of the people, because in
> my lifetime it never has--therefore, I have no expectation that it will.
Just to make sure everyone is clear on this: "it never has" refers to
"protects", not "fails to protect"; i.e., in my lifetime I have never seen
the U.S. government consistently protect the interest of U.S. citizens,
except by accident.
Amanda Walker
InterCon Systems Corporation
From: pmetzger@snark.shearson.com (Perry E. Metzger)
Subject: Re: Once tapped, your code is no good any more.
Organization: Partnership for an America Free Drug
Distribution: na
Lines: 14
res@colnet.cmhnet.org (Rob Stampfli) writes:
>
>Wouldn't a a second monitor of similar type scrolling gibberish and adjacent
>to the one being used provide reasonable resistance to tempest attacks?
It would be in a different location, so a directional antenna could
probably lock in on just the one monitor. Failing that, a phased array
could likely seperate the signals. Admittedly, this is expensive, but
so is all the rest of this stuff anyway.
--
Perry Metzger		pmetzger@shearson.com
--
Laissez faire, laissez passer. Le monde va de lui meme.
From: arussell@austin.ibm.com (AG Russell)
Subject: Re: Off the shelf cheap DES keyseach machine (Was: Re: Corporate acceptance of the wiretap chip)
Originator: arussell@pal500.austin.ibm.com
Organization: IBM Austin
Lines: 29
In article <1993Apr21.001230.26384@lokkur.dexter.mi.us>, scs@lokkur.dexter.mi.us (Steve Simmons) writes:
> smb@research.att.com (Steven Bellovin) writes:
>
> >Thousands?  Tens of thousands?  Do some arithmetic, please...  Skipjack
> >has 2^80 possible keys.  Let's assume a brute-force engine like that
> >hypothesized for DES:  1 microsecond per trial, 1 million chips.  That's
> >10^12 trials per second, or about 38,000 years for 2^80 trials.  Well,
> >maybe they can get chips running at one trial per nanosecond, and build
> >a machine with 10 million chips.  Sure -- only 3.8 years for each solution.
>
> Normally I'd be the last to argue with Steve . . . but shouldn't that
> read "3.8 years for *all* solutions".  I mean, if we can imagine the
> machine that does 1 trial/nanosecond, we can imagine the storage medium
> that could index and archive it.
At the company I worked for previously, I received a file that was des encryped
and the person that had sent it, went on vaction.  Rather than wait two weeks
I set up a straight frontal attack with one key at a time.  It only took two(2)
days to crack the file.  No, I don't have any faith in DES.
A.G.
--
A.G. Russell   Dept A06S  OLTP section of PALS Group   VM ID  SC39093 at AUSVM1
Email  arussell@austin.ibm.com       Phone 512-838-7953        TieLine 678-7953
These are my views, on anyone else they would look silly. FREE THE BERKELEY 4.4
From: pat@rwing.UUCP (Pat Myrto)
Subject: Re: White House Public Encryption Management Fact Sheet
Article-I.D.: rwing.2087
Distribution: na
Organization: Totally Unorganized
Lines: 52
In article <19APR199313020883@charon.gsfc.nasa.gov> paul@charon.gsfc.nasa.gov (Paul Olson) writes:
>In article <1qnav4$r3l@transfer.stratus.com>, cme@ellisun.sw.stratus.com (Carl Ellison) writes...
>>In article <C5LGAz.250@dove.nist.gov> clipper@csrc.ncsl.nist.gov (Clipper Chip Announcement) writes:
>>
>>>Further, the Attorney General
>>
> [ ... good post describing what is in store for us deleted ... ]
>
>It's also interesting to note that two months ago Rush Limbaugh said that
>Clinton would have the "plumbers" out in force shortly.  Clinton and his
>henchmen firmly believe in strong ubiquitous government control.  Anytime a
>leader believes in that, the leader will use every means possible to retain
>that control and take more.
>
>WE have to take OUR government back.  Otherwise we will end up living in the
>equivalent of a high-tech third world dictatorship.  We have to take
>responsibility for ourselves, our personal welfare, and our actions.
I totally agree.  But how do you propose we take government back?  They
obviously don't listen to the people or want the people to know who is
responsibile for what (a person telnetted the site of the Clipper chip
release, to see what the entity 'clipper' was, and got a few lists.
BUt when another person tried a bit later, the commands were disabled)
Does not sound like an Administration that wants to have any accountability
or information they don't control given to the people.  The secret
development and implimentation of the Clipper Chip decision further
backs that up.  You can bet unaurhorized encryption methods and software
will be considered 'terrorist tools' and also subject to civil forfeiture,
along with the systems that are running it.  YOU WATCH, SEE IF I AM WRONG.
The government is not going to be very cooperative about the people taking
it back.  And they have all the resources, unlimited access to the media
for propeganda, and almost all the guns (soon to be ALL the guns if
Clinton's agenda succeeds)...   Those that do not play ball?  Waco
might be a good example of what to expect...  The warrant (just released)
stated the reason for the raid was the BDs spent a very large sum
for weapons, over an undetermined amount of time.  I don't recall
spending a lot of money on guns, etc being illegal ... yet, that is.
Clinton might go down in history as the worst thing to ever happen to
the US of A. ... Now to be known as the 'Peoples Socalist Democratic
Republic of America'  (PSDRA).
Big Brother is LISTENING!!!
Hail Big Brother... (and Sister...?)  only ten years late!!!
--
pat@rwing.uucp      [Without prejudice UCC 1-207]     (Pat Myrto) Seattle, WA
If all else fails, try:       ...!uunet!pilchuck!rwing!pat
WISDOM: "Only two things are infinite; the universe and human stupidity,
and I am not sure about the former."              - Albert Einstien
From: cmsph02@nt.com  (Steven Holton)
Subject: Re: Do we need the clipper for cheap security?
Organization: Northern Telecom, Inc.
Lines: 25
In article <1r1f62$rh5@news.intercon.com>, amanda@intercon.com (Amanda
Walker) wrote:
> One thing that Clipper offers is interoperability, at a higher degree of
> security than we currently have in non-proprietary voice encryption systems.
> This means it will be cheaper than anyone's proprietary scheme, and easier to
^^^^^^^
Probably cheaper than you think.  I'll bet some of my (and yours)
tax dollars become a subsidy for these chips.  If these chips don't
sell well, what's to stop the US government from 'giving' them
away (in the interest of National Security)?
> deploy.  This is, of course, either a bug or a feature depending on how you
> look at it :).
>
> Amanda Walker
> InterCon Systems Corporation
--
Steven P. Holton
Network Administrator - RTP FAST
Northern Telecom, Inc.
Replies To:  cmsph02@nt.com
on bounce: [ sholton@aol.com | 70521.2430@compuserve.com ]
"Opinions expressed here are my own."
From: pdc@dcs.ed.ac.uk (Paul Crowley)
Subject: Re: Would "clipper" make a good cover for other encryption method?
Reply-To: pdc@dcs.ed.ac.uk (Paul Crowley)
Organization: Edinburgh University
Lines: 17
Quoting strnlght@netcom.com (David Sternlight) in article <strnlghtC5t3nH.Is1@netcom.com>:
>In article <1993Apr20.032623.3046@eff.org> kadie@eff.org (Carl M. Kadie) writes:
>
>
>>So, don't just think of replacements for clipper, also think of front
>>ends.
>
>This only makes sense if the government prohibits alternative non-escrowed
>encryption schemes. Otherwise, why not just use the front end without
>clipper?
Because that will make private encryption stick out like a sore thumb
and the government will start to take a sharp interest in everything you
do.
__                                  _____
\/ o\ Paul Crowley   pdc@dcs.ed.ac.uk \\ //
/\__/ Trust me. I know what I'm doing. \X/  Fold a fish for Jesus!
From: pat@rwing.UUCP (Pat Myrto)
Subject: Re: Once tapped, your code is no good any more.
Article-I.D.: rwing.2088
Distribution: na
Organization: Totally Unorganized
Lines: 52
In article <1993Apr20.161838.13213@coop.com> felixg@coop.com (Felix Gallo) writes:
<pat@rwing.UUCP (Pat Myrto) writes:
<
<>If the Clinton Clipper is so very good, [...]
<
<Please note that Bill Clinton probably has little if anything to do
<with the design, implementation or reasoning behind this chip or behind
<any "moves" being made using this chip as a pawn.
Uh, I notice he has not either asked for or allowed public input, and he damn
sure has not stopped it...
<Remember, when you elect a president of the united states, it's not
<the case that all the Republicans, etc. in the NSA and FBI and CIA
<immediately pack their bags and get replaced by a team of fresh young
<Democrats.  Most of the government -- say, 96% -- is appointed or
<hired rather than elected.  Since this Clipper device has been in
<production for over six months, it probably has little or no
<foundation in the currently elected Democratic Executive body.
Again, if it was something Clinton didn't like, how come he did not
stop it, or get PUBLIC input before implimenting the DECISION?  He
sure has asserted his authority on other things he did not agree with
from the Bush administrationk, I notice.   He is the president, therefore
he is RESPONSIBLE for the actions of the Execuitive Branch.  I have
not the slightest bit of doubt you would be holding Bush or Reagan
to that standard had they been in office when this thing was cast into
stone...
<>BTW - those who suggest that this is just an attack on Clinton, believe
<>this:  I would be going ballistic reagardless WHO seriously proposed
<>this thing.  It is just another step in a gradual erosion of our rights
<>under the Constitution or Bill of Rights.  The last couple of decades
<>have been a non-stop series of end-runs around the protections of the
<>Constitution.  It has to stop.  Now is as good a time as any, if it
<>isn't too late allready.
<
<Could be.  However, the sky hasn't fallen yet, Chicken Little.
Thanks for the name-calling.  That really makes your position higly
credible.  Lenin had a term for folks with your outlook.  Do you REALLY
have THAT MUCH faith in the trustworthiness and honesty of the government
that is primarily concerned with people control?   I suspect you will
be in for an unpleasant surprise.  I would just as soon see this nipped
in the bud while/if it still can be done, instead of waiting for yet
more abridgements of our Bill of Rights, thank you...
--
pat@rwing.uucp      [Without prejudice UCC 1-207]     (Pat Myrto) Seattle, WA
If all else fails, try:       ...!uunet!pilchuck!rwing!pat
WISDOM: "Only two things are infinite; the universe and human stupidity,
and I am not sure about the former."              - Albert Einstien
From: pat@rwing.UUCP (Pat Myrto)
Subject: Re: Once tapped, your code is no good any more.
Article-I.D.: rwing.2089
Distribution: na
Organization: Totally Unorganized
Lines: 45
In article <1993Apr19.193528.5655@cs.ucla.edu> geoff@ficus.cs.ucla.edu (Geoffrey Kuenning) writes:
>In article <2073@rwing.UUCP> pat@rwing.UUCP (Pat Myrto) writes:
>
>> fishing expeditions without the target's knowlege.  Don't give up the
>> right to be safe from that - that should be non-negotiable, and Clinton
>> and Co. know it (which is probably why they quietly developed this thing,
>> figuring if they get it this far, they can ram it on through).
>
>It always amazes me how quick people are to blame whatever
>administration is current for things they couldn't possibly have
>initiated.  This chip had to take *years* to develop, yet already
>we're claiming that the Clinton administration sneaked it in on us.
>Bullshit.  The *Bush* administration and the career Gestapo were
>responsible for this horror, and the careerists presented it to the
>new presidency as a fait accompli.  That doesn't excuse Clinton and
>Gore from criticism for being so stupid as to go for it, but let's lay
>the body at the proper door to start with.
You are so correct - Clinton did not initiate it.  He just cast it in
GRANITE by implimenting, NOT stopping the DECISION.  I also stated in another
post I don't give a damn what administration does it, I still find it
totally unacceptable, and whoever impliments it or rams it down our throats
ought to be run out of office.
Also, Bush was not trying to deprive us of our Second Amendment rights.
Clinton is BUSTING HIS BUTT in that regard.  That reveals a total difference
in philosophy.  Clinton appears to support the idea of TOTAL people
control.  Eavesdropping whenever they feel like it, no real security
for the common person, and no ability to defend oneself against illegal
attack, from whatever source.  "Trust us, we will protect (and control)
you... if we don't find it inconvenient..."
Clinton has also shown his utter contempt for public disclosure and
accountability, as well.  He had plenty of time to change the policy.
HE DIDN'T.  HE EXPANDED ON IT.
I bet had Bush been in office, you would be in there howling louder
than I.
--
pat@rwing.uucp      [Without prejudice UCC 1-207]     (Pat Myrto) Seattle, WA
If all else fails, try:       ...!uunet!pilchuck!rwing!pat
WISDOM: "Only two things are infinite; the universe and human stupidity,
and I am not sure about the former."              - Albert Einstien
From: pdc@dcs.ed.ac.uk (Paul Crowley)
Subject: Re: Organized Lobbying for Cryptography
Reply-To: pdc@dcs.ed.ac.uk (Paul Crowley)
Organization: Edinburgh University
Distribution: inet
Lines: 12
Quoting jgfoot@minerva.cis.yale.edu in article <1r3jgbINN35i@eli.CS.YALE.EDU>:
>Perhaps these encryption-only types would defend the digitized porn if it
>was posted encrypted?
>These issues are not as seperable as you maintain.
In fact, since effective encryption makes censorship impossible, they
are almost the same issue and they certainly fall into the brief of the
EFF.
__                                  _____
\/ o\ Paul Crowley   pdc@dcs.ed.ac.uk \\ //
/\__/ Trust me. I know what I'm doing. \X/  Fold a fish for Jesus!
From: denning@guvax.acc.georgetown.edu
Subject: REVISED TECHNICAL SUMMARY OF CLIPPER CHIP
Distribution: world
Organization: Georgetown University
Lines: 167
Here is a revised version of my summary which corrects some errors
and provides some additional information and explanation.
THE CLIPPER CHIP: A TECHNICAL SUMMARY
Dorothy Denning
Revised, April 21, 1993
INTRODUCTION
On April 16, the President announced a new initiative that will bring
together the Federal Government and industry in a voluntary program
to provide secure communications while meeting the legitimate needs of
law enforcement.  At the heart of the plan is a new tamper-proof encryption
chip called the "Clipper Chip" together with a split-key approach to
escrowing keys.  Two escrow agencies are used, and the key parts from
both are needed to reconstruct a key.
CHIP CONTENTS
The Clipper Chip contains a classified single-key 64-bit block
encryption algorithm called "Skipjack."  The algorithm uses 80 bit keys
(compared with 56 for the DES) and has 32 rounds of scrambling
(compared with 16 for the DES).  It supports all 4 DES modes of
operation.  The algorithm takes 32 clock ticks, and in Electronic
Codebook (ECB) mode runs at 12 Mbits per second.
Each chip includes the following components:
the Skipjack encryption algorithm
F, an 80-bit family key that is common to all chips
N, a 30-bit serial number (this length is subject to change)
U, an 80-bit secret key that unlocks all messages encrypted with the chip
The chips are programmed by Mykotronx, Inc., which calls them the
"MYK-78."  The silicon is supplied by VLSI Technology Inc.  They are
implemented in 1 micron technology and will initially sell for about
$30 each in quantities of 10,000 or more.  The price should drop as the
technology is shrunk to .8 micron.
ENCRYPTING WITH THE CHIP
To see how the chip is used, imagine that it is embedded in the AT&T
telephone security device (as it will be).  Suppose I call someone and
we both have such a device.  After pushing a button to start a secure
conversation, my security device will negotiate an 80-bit session key K
with the device at the other end.  This key negotiation takes place
without the Clipper Chip.  In general, any method of key exchange can
be used such as the Diffie-Hellman public-key distribution method.
Once the session key K is established, the Clipper Chip is used to
encrypt the conversation or message stream M (digitized voice).  The
telephone security device feeds K and M into the chip to produce two
values:
E[M; K], the encrypted message stream, and
E[E[K; U] + N; F], a law enforcement field ,
which are transmitted over the telephone line.  The law enforcement
field thus contains the session key K encrypted under the unit key U
concatenated with the serial number N, all encrypted under the family
key F.  The law enforcement field is decrypted by law enforcement after
an authorized wiretap has been installed.
The ciphertext E[M; K] is decrypted by the receiver's device using the
session key:
D[E[M; K]; K] = M .
CHIP PROGRAMMING AND ESCROW
All Clipper Chips are programmed inside a SCIF (Secure Compartmented
Information Facility), which is essentially a vault.  The SCIF contains
a laptop computer and equipment to program the chips.  About 300 chips
are programmed during a single session.  The SCIF is located at
Mykotronx.
At the beginning of a session, a trusted agent from each of the two key
escrow agencies enters the vault.  Agent 1 enters a secret, random
80-bit value S1 into the laptop and agent 2 enters a secret, random
80-bit value S2. These random values serve as seeds to generate unit
keys for a sequence of serial numbers.  Thus, the unit keys are a
function of 160 secret, random bits, where each agent knows only 80.
To generate the unit key for a serial number N, the 30-bit value N is
first padded with a fixed 34-bit block to produce a 64-bit block N1.
S1 and S2 are then used as keys to triple-encrypt N1, producing a
64-bit block R1:
R1 = E[D[E[N1; S1]; S2]; S1] .
Similarly, N is padded with two other 34-bit blocks to produce N2 and
N3, and two additional 64-bit blocks R2 and R3 are computed:
R2 = E[D[E[N2; S1]; S2]; S1]
R3 = E[D[E[N3; S1]; S2]; S1] .
R1, R2, and R3 are then concatenated together, giving 192 bits. The
first 80 bits are assigned to U1 and the second 80 bits to U2.  The
rest are discarded.  The unit key U is the XOR of U1 and U2.  U1 and U2
are the key parts that are separately escrowed with the two escrow
agencies.
As a sequence of values for U1, U2, and U are generated, they are
written onto three separate floppy disks.  The first disk contains a
file for each serial number that contains the corresponding key part
U1.  The second disk is similar but contains the U2 values.  The third
disk contains the unit keys U.  Agent 1 takes the first disk and agent
2 takes the second disk.  Thus each agent walks away knowing
an 80-bit seed and the 80-bit key parts.  However, the agent does not
know the other 80 bits used to generate the keys or the other 80-bit
key parts.
The third disk is used to program the chips.  After the chips are
programmed, all information is discarded from the vault and the agents
leave.  The laptop may be destroyed for additional assurance that no
information is left behind.
The protocol may be changed slightly so that four people are in the
room instead of two.  The first two would provide the seeds S1 and S2,
and the second two (the escrow agents) would take the disks back to
the escrow agencies.
The escrow agencies have as yet to be determined, but they will not
be the NSA, CIA, FBI, or any other law enforcement agency.  One or
both may be independent from the government.
LAW ENFORCEMENT USE
When law enforcement has been authorized to tap an encrypted line, they
will first take the warrant to the service provider in order to get
access to the communications line.  Let us assume that the tap is in
place and that they have determined that the line is encrypted with the
Clipper Chip.  The law enforcement field is first decrypted with the
family key F, giving E[K; U] + N.  Documentation certifying that a tap
has been authorized for the party associated with serial number N is
then sent (e.g., via secure FAX) to each of the key escrow agents, who
return (e.g., also via secure FAX) U1 and U2.  U1 and U2 are XORed
together to produce the unit key U, and E[K; U] is decrypted to get the
session key K.  Finally the message stream is decrypted.  All this will
be accomplished through a special black box decoder.
CAPSTONE: THE NEXT GENERATION
A successor to the Clipper Chip, called "Capstone" by the government
and "MYK-80" by Mykotronx, has already been developed.  It will include
the Skipjack algorithm, the Digital Signature Standard (DSS), the
Secure Hash Algorithm (SHA), a method of key exchange, a fast
exponentiator, and a randomizer.  A prototoype will be available for
testing on April 22, and the chips are expected to be ready for
delivery in June or July.
ACKNOWLEDGMENT AND DISTRIBUTION NOTICE.  This article is based on
information provided by NSA, NIST, FBI, and Mykotronx.  Permission to
distribute this document is granted.
From: ns111310@LANCE.ColoState.Edu (Nathaniel Sammons)
Subject: Re: I have seen the lobby, and it is us
Nntp-Posting-Host: casco.lance.colostate.edu
Organization: Colorado State U. Engineering College
Lines: 33
In article <1993Apr21.163929.21149@eff.org> A. Charles Gross <acg@eff.org> writes:
>Certainly, with our way-cool Internet powers of
>organization, we can act in the same way, if such action is appropriate.
>
>As long as we are kept informed of events, anyone on this bboard can make
>a call to action.  Hopefully, we're a strong enough community to act on
>those calls.  I realize this is a little optomistic, and I'm glad EFF is
>working in the loop on these issues, but don't underestimate the
>potential of the net for political action.
>
>Adam
>* I speak for myself
I second the motion.
All in favor?
BTW>> a few days ago, Charles Fee <CXF111@psuvm.psu.edu> posted the names,
addresses, and phone numbers (voice and fax) of almost all the 103rd
congress's members.  This info, along witha great number of cabinet men, etc...
I captured it, as did many others, I am sure.
We should single out a few of the people on the list, and bombard them
with lobbying against the Clipper Chip, et al.
-nate
o---------------------------+======================================o
| "I hate quotations.       |     This message brought you by      |
|   Tell me what you know." |   Nate Sammons, and the number 42.   |
|    --Ralph Waldo Emerson  |  ns111310@longs.lance.colostate.edu  |
o---------------------------+======================================o
From: ariel@world.std.com (Robert L Ullmann)
Subject: Re: Why the algorithm is secret
Organization: The World in Boston
Distribution: na
Lines: 27
Exactly.
But I'll add another observation: if the chip does become a standard,
the algorithm won't _remain_ secret.
Leaving the government with the only remaining option: to make use
of un-escrowed keys illegal. Which won't begin to bother the terrorists
and child abusers the government is so fond of referring to.
Note that the Federalist papers stress _one_ reason for the right
of citizens to bear arms: to defend themselves _against_ the army.
_Our_ army.
IMHO the _primary_ purpose of private crypto is defend ourselves
_against_ the government. The odd terrorist I'm not worried about;
the goverment damages my quality of life every day.
Rob
--
Robert Ullmann		Ariel@World.STD.COM	+1 508 879 6994 x226
Quand Maigret poussa la porte du Tabac Fontaine, vers une heure et demie,
le patron du bar, qui venait de se lever, descendait lentement un escalier
en colima��on qui s'amor��ait dans l'arri��re-salle. ... Arriv�� derri��re le
comptoir, il repousa le gar��on d'un geste n��gligent de la main, saisit
une bouteille de vin blanc, un verre, m��langea au vin de l'eau min��rale et,
la t��te renvers��e en arri��re, se gargarisa.  -- Simenon
[text is ISO 10646 UTF-1 universal character set]
From: carl@lvsun.com (Carl Shapiro)
Subject: Re: Estimating Wiretap Costs/Benefits
Summary: Benefits probably greater than thought
Organization: Las Vegas Sun
Lines: 16
In article <1993Apr20.203756.20667@kronos.arc.nasa.gov> hanson@kronos.arc.nasa.gov (Robin Hanson) writes:
>A rough estimate suggests that wiretaps are worth about five million
>dollars per year to U.S. law enforcement agencies.  (In 1990, 872 U.S.
>wiretaps led to 2057 arrests, while total police expenditures of $28
>billion led to 11.25 million arrests [ref US Statistical Abstracts].)
>I'm working on estimating this wiretap benefit more accurately, but
You seem to be assuming that all arrests are of equal value, and that
the use of wiretaps is spread uniformly among them.
Given this comparatively tiny number of wiretaps, and the associated
difficulty and cost involved (judges, technicians, etc) I expect that
law enforcement reserves the use of wiretaps for the most valuable
cases.  Since the "value" of an arrest can vary over an enormous range
(eg. jaywalking -> mass murder) I think your $5 million estimate may
be too low by a couple of orders of magnitude.
From: ebrandt@jarthur.claremont.edu (Eli Brandt)
Subject: Re: The [secret] source of that announcement
Organization: Harvey Mudd College, Claremont, CA 91711
Lines: 12
In article <1r3hgqINNdaa@uwm.edu> Rick Miller <rick@ee.uwm.edu> writes:
>jbotz@mtholyoke.edu (Jurgen Botz) writes:
>>Seems like sombody didn't like your snooping around, Marc.
>
>Or, the more *likely* explanation is that Marc is spoofing.
While I didn't try the expansion personally, I know of at least two
other people who did and got the same results.  Your allegation is
incorrect at best.
PGP 2 key by finger or e-mail
Eli   ebrandt@jarthur.claremont.edu
From: mrr@scss3.cl.msu.edu (Mark Riordan)
Subject: DOS 6.0 compression API: partial answer
Organization: Michigan State University
Lines: 21
NNTP-Posting-Host: scss3.cl.msu.edu
X-Newsreader: TIN [version 1.1 PL8]
For those of you looking for information on MS-DOS 6.0's
file system compression API:
Today I called Microsoft's DOS 6.0 hotline at (800)228-7007.
They told me that the DOS 6.0 Resource Kit had the specifications
for the compression interface.  The Resource Kit costs $19.95,
plus tax and $5 shipping.
I ordered a copy and will post further when I get it and know more
about it.  I am posting now because the order turnaround is 15
working days.
If anyone knows for sure where's there's a good
source of info on this API, please speak up.  I am
slightly skeptical about the Resource Kit's likelihood
of having detailed programming info.
Mark R.  mrr@ripem.msu.edu
(posted also to sci.crypt, since the API could presumably also
be used for file system encryption.)
From: eachus@spectre.mitre.org (Robert I. Eachus)
Subject: Re: Off the shelf cheap DES keyseach machine (Was: Re: Corporate acceptance of the wiretap chip)
In-Reply-To: mjr@tis.com's message of 21 Apr 1993 21:28:13 GMT
Nntp-Posting-Host: spectre.mitre.org
Organization: The Mitre Corp., Bedford, MA.
<1993Apr20.192105.11751@ulysses.att.com>
<1993Apr21.001230.26384@lokkur.dexter.mi.us> <1r4e9d$pdo@sol.TIS.COM>
Lines: 19
Don't get fooled by exponents 2^80 (possible keys) is not in the
same league with 10^80 (particles in the universe).  2^80 < 10^25.
Remember Avagadro's number?  There are about that many elementary
particles (not molecules) in one mole.  Pretty small universe!  Or if
you can put 5 Gigabytes on one tape, you would need about 10 trillion
tapes (allowing several bytes per entry).  Still more than all of the
existing magnetic media on the planet, but wait a few years.  (I'm
including existing audio and video cassettes in the total.  Ten
trillion is about 2,000 per person worldwide...  Gives new meaning to
the suspicions of hiden messages.)
--
Robert I. Eachus
with Standard_Disclaimer;
use  Standard_Disclaimer;
function Message (Text: in Clever_Ideas) return Better_Ideas is...
From: dcd@se.houston.geoquest.slb.com (Dan Day)
Subject: Re: The Escrow Database.
Nntp-Posting-Host: castor.se.houston.geoquest.slb.com
Organization: GeoQuest System, Inc. Houston
Lines: 17
In article <1993Apr20.021846.2423@shearson.com> pmetzger@snark.shearson.com (Perry E. Metzger) writes:
>
>each of the two escrow databases. Fits conveniently on a single very
>valuable Exabyte tape. This can only get easier with time, but who
>cares -- I can already hold all the clipper keys in the country in my
>pocket on two 8mm tapes.
Excellent point, and there's a related point I'd like to make.
They'll have to back up these databases themselves, won't they?
How many tape copies will there be, and how secure will the
tapes be?  If they store them off-site, it wouldn't be too
hard to hijack them in transit.  If they're all kept on-site,
one good bomb attack by some group intent on freeing us from
the threat of government snooping will take care of the problem
once and for all.  I can see it now -- "Hi, we're from the
government and we, um, misplaced our copy of your key.  Could
you mail us a copy?"
From: ebrandt@jarthur.claremont.edu (Eli Brandt)
Subject: Re: Would "clipper" make a good cover for other encryption method?
Organization: Harvey Mudd College, Claremont, CA 91711
Lines: 22
In article <1993Apr20.032623.3046@eff.org> kadie@eff.org (Carl M. Kadie) writes:
>Clipper might be a good way to cover the use of another layer of
>encryption.
Could somebody provide an overview of the proposed systems using the
chip?  (Ought to see if ATT has a spec sheet)  Skipjack sounds like a
normal digital encryption algorithm, so the data path will have to be
voice --> digitize --> compress --> encrypt
Compression will be necessary to fit the data on the wire, unless
they want to wait for ISDN (that we should be so lucky...).  Feeding
pre-encrypted data into the compressor will cause it to chuckle at
you; you'd have to tap into the guts of the phone and hack either
the compressed data stream, or selected parts of the output stream
before it hits the modem.  Unless you want to pay for two fast
modems on top of the encryption, and just plug the box in between
your phone and the wall.
>- Carl
PGP 2 key by finger or e-mail
Eli   ebrandt@jarthur.claremont.edu
From: habs@panix.com (Harry Shapiro)
Subject: Re: The [secret] source of that announcement
Organization: PANIX Public Access Unix, NYC
Lines: 65
In <1r1om5$c5m@slab.mtholyoke.edu> jbotz@mtholyoke.edu (Jurgen Botz)
writes:
>Even more interesting: the SMTP server at csrc.ncsl.nist.gov no longer
>recognizes the 'expn' and 'vrfy' commands...
>   telnet csrc.ncsl.nist.gov smtp
>   Trying 129.6.54.11...
>   Connected to csrc.ncsl.nist.gov.
>   Escape character is '^]'.
>   220 first.org sendmail 4.1/NIST ready at Tue, 20 Apr 93 17:01:34 EDT
>   expn clipper
>   500 Command unrecognized
>Seems like sombody didn't like your snooping around, Marc.
Then it is a good thing we already have this:
The csspub mailing list: csspab@mail-gw.ncsl.nist.gov, and address on
the clipper mailing list, seems to contain basically the members of
the NIST security board.
In addition to the names already posted, their true names are as
follows:
burrows@ecf = James Burrows a director of NIST's National Computer
Systems Laboratory
mcnulty@ecf = F. Lynn McNulty an associate director for computer
security at the National Institute of Standards and Technology's
Computer Systems Laboratory
Gangemi@dockmaster.ncsc.mil = Gaetano Gangemi is director of the
secure systems program at Wang Laboratories Inc. He wrote: Computer
Security Basics by Deborah Russell and G. T.  Gangemi, Sr. -1991,
O'Reilly and Associates
slambert@cgin.cto.citicorp.com = Sandra Lambert is vice-president of
information security at Citibank, N.A.
lipner@mitre.org = Lipner is Mitre Corp.'s director of information
systems.
gallagher@dockmaster.ncsc.mil = Patrick Gallagher, director of the
National Security Agency's National Computer Security Center and a
security board member
walker@tis.com = Stephen Walker a computer security expert and
president of Trusted Information Systems, Inc. in Glenwood, Md
willis@rand.org = Willis H.  Ware a the Rand Corp.  executive who
chairs the security board.
whitehurst@vnet.ibm.com = William Whitehurst is a security board
member and director of IBM Corp.'s data security programs.
--
Harry Shapiro  				      habs@panix.com
List Administrator of the Extropy Institute Mailing List
Private Communication for the Extropian Community since 1991
--
Harry Shapiro  				      habs@panix.com
List Administrator of the Extropy Institute Mailing List
Private Communication for the Extropian Community since 1991
From: tfs@gravity.gmu.edu (Tim Scanlon)
Subject: Re: Secret algorithm [Re: Clipper Chip and crypto key-escrow]
Summary: Whatever...
Keywords: Hmm...
Organization:  George Mason University, Fairfax Va.
Distribution: world
Expires: 06/31/93
Lines: 65
After reading the debate over the Clipper, I have a few things to
add.
First, most of the people I know who activly use encryption
privately do not care about most of the issues that surround this debate,
and any questions about what is or is not ok to use in the US. All they
care about is wether or not what they are using is secure or not. That,
after all IS the bottom line.
Second, if I look at all the people I know who use any form
of encryption at all, and this group spans people from the morons who
still insist that the DES is a good and secure standard, to people
looking at trying to improve upon existing strategies, I can not think
of anyone of them who would approve blindly of a strategy that leaves
their methods open to abuse. The Clipper does this, because people make
mistakes by nature, and the US government is made up of people who are
just as vulnerable to mistakes as everyone else.
Third, since most of the people I know are at least marginaly
familiar with the vulnerabilities present in current software encryption
stratigies, I can't see how most of them are going to blindly trust that
someone will not figure out a good way to compromise the Clipper Chip.
That despite any strengths or weaknesses that may exist in it. So, I can
not see a high degree of confidence developing in the chip.
Fourth, when it comes to criminal abuse, sure there are many stupid
people out there. And yes, some will be open to being caught via the
built in back door of the Clipper Chip. However, anyone who is going to
do any serious investigation of how best to secure their data is going
to run into that problem pretty damned fast and, I would assume, start
looking around for other easily obtainible methods of encryption.
If nothing else were avalible, none of this would be an issue. However,
the truth is that most private encryption users that I've ever run into
simply do not give a damn about the legal status of RSA or PGP or anything
else. If it works, they use it. This is not going to change either. I do
not think for a moment that anyone with serious criminal intent will be
slowed down by the advent of the Clipper Chip. It is all to easy to
convert encrypted data into unintellgible garbage as it is, if anything,
the Clipper Chip just adds another tool to the user.
The bottom line here is that people will use what works, and
unavoidibly, I'm sure most criminals would rather face an encryption
related charge than one which could potentialy lead to death penalty
charges in the case of criminals who murder as part of their conspiricy.
The other thing that has struck me since the advent and wide
useage of public encryption has begun is that quite simply the cat is
out of the bag (Or if you have an interest in snooping, Pandora's Box
has been opened), and this is not going to change. I've seen a blindness
to this that I've found utterly stunning, and the Clipper Chip, along
with the way it has been presented only confirms this to me to a larger
degree.
Sincerly,
Tim Scanlon
--
tfs@gravity.gmu.edu
From: ebrandt@jarthur.claremont.edu (Eli Brandt)
Subject: Re: Estimating Wiretap Costs/Benefits
Organization: Harvey Mudd College, Claremont, CA 91711
Lines: 23
In article <rlglendeC5t133.En3@netcom.com> rlglende@netcom.com (Robert Lewis Glendenning) writes:
>First, what the fuck is NASA doing wasting my tax dollars doing
>policy papers on stuff far outside of their purvew/mission?
I don't think they're paying for it.
>Do us a favor.  Resign rather than right this paper for NASA.  Go
>do useful work for the society.
Useful?  I find his estimate of the annual value to law enforcement
of $5 million quite useful, if rough (e.g. wiretaps may be
preferentially used on otherwise-hard-to-catch criminals, resulting
in an underestimate).  This comes to twenty cents a head over the
U.S. population.  I would find some rigorous numbers on this quite
useful -- it would make for nice slogans: "Your privacy is worth
$0.37", or whatever it turns out to be.
>Lew Glendenning		rlglende@netcom.com
PGP 2 key by finger or e-mail
Eli   ebrandt@jarthur.claremont.edu
From: makey@VisiCom.COM (Jeff Makey)
Subject: Re: Once tapped, your code is no good any more.
Distribution: na
Organization: VisiCom Laboratories, Inc., San Diego, California
Lines: 15
In article <C5so84.Hxv@demon.co.uk> Graham Toal <gtoal@gtoal.com> writes:
>I am *completely* baffled by why Dorothy Denning has chosen
>to throw away her academic respectability like this.
She hasn't.  Dorothy Denning has spent many years earning the
professional respect of her colleagues, and something won in this
manner is not easily lost.  Her support of the clipper -- no matter
how unpopular that position may be -- serves far more to enhance the
clipper's respectability than to diminish her own.
:: Jeff Makey
Department of Tautological Pleonasms and Superfluous Redundancies Department
Disclaimer: All opinions are strictly those of the author.
Domain: makey@VisiCom.COM    UUCP: nosc!visicom!makey
From: koontzd@phobos.lrmsc.loral.com (David Koontz )
Subject: Will FEDs troll for mutilated law enforcement blocks?
Originator: koontzd@phobos
Organization: Loral Rolm Computer Systems
Lines: 121
From Denning:
the Skipjack encryption algorithm
F, an 80-bit family key that is common to all chips
N, a 30-bit serial number
U, an 80-bit secret key that unlocks all messages encrypted with the chip
E[M; K], the encrypted message stream, and
E[E[K; U] + N; F], a law enforcement block.
Where the session key is K, and is transmitted encrypted in the unit Key U.
Which along with the serial number N is encrypted in the Family key F.
Presumably the protocol can be recovered (if by nothing else, differential
analysis).
Postulate if you will, a chip (or logic) sitting between the clipper chip
and its communications channel.  The function of this spoof chip is twofold:
1) Transmit Channel
The spoof chip XORs the 30 bit encrypted serial number with
a secondary keying variable.  This renders the serial number
unrecoverable with just the family key
2) Receive Channel
The spoof chip XORs the incoming encrypted serial number
with a secondary keying variable (assuming integrity of the
law enforcement block is necessary for local operation -
checksums, sequence control, etc.).
This has the net result of hiding the serial number.  It is probable theere is
a known plaintext pattern used as a filler in the block containing N (34 bits
as used in generating U, U1,U2) correctness of the law enforcement block
can be determined with only the family key F.  Whereas, no one has proposed
Federal Agencies be denied F, and because they could recover it themselves,
The correctness of the serial number can be tested by examining the pad bits
of N in E[N; F].
The one could selectively alter the law enforcement block as above, but the
mutilation could be detected.  A better approach would be to mutilate the
entire law enforcement block.  If it were done with a group encryption scheme
such as DES or (presumably) Skipjack, the chances the law enforcement block
can be recovered are lessened.
What do you want to bet the transmission protocol can be recognized and the
serial numbers decrypted in a target search?  When digital transmission
becomes widely available, would there be a requirement that clipper protocol
transmissions be refused when containing mutilated law enforcement blocks?
One way to avoid notice, would be to spoof protocol information of the block
containing M, as well as spoofing the law enforcement block.
The goal is to use a secure communications scheme, without redress to
detection or key K interception (contained encrypted within the law
enforcement block).  The data stream is returned to its original state
for use by the clipper chip (or system) if required, for proper operation.
It is somewhat improbable that the entire protocol will be contained within
the clipper chip, yet likely that sequence of events will be tested for,
requiring a valid law enforcement block to be received before accepting
and decrypting E(M; K);
The spoof chip could be implemented anywhere in the protocols, including
on the resulting serial data stream.  Existing clipper products could
be subborned.  After all, they are high security encryption systems right?
Super encipherment/encryption could allow the chip to be used without
redress to detection of the use of the chip, or disclosure of the serial
number.  Security must be adequate to deny the serial number, which should
not be recoverable by other means.  One can see the use of cut outs for
procurring clipper phones, or once the number of units is high enough,
stealing them.  It would be a mistake on the part of authority, but nice
from a point of privacy, if the serial number N were not associated with
a particular clipper chip or lot of chips through the manufacturing and
distribution process.  Hopefully the list of known missing or stolen
clipper serial numbers N encrypted with F, and the protocols are not
sufficient plaintext to attact the super encrypted clipper stream.
This could be further made difficult by altering the temporal and or
spatial relationship of the clipper stream to that of the super encrypted
stream.
Detection of an encrypted stream could tip off the use of the aforementioned
scheme.
******************************************************************************
If you could capture valid law enforcement blocks not your own, and use
them in a codebook sustitution with your own, where they point to a valid
law enforcement block stored in a library utilizing a session key matching
the remainder of the transmission, you could simply out and out lie, yet
deliver to monitoring and/or hostile forces a seemingly valid law enforcement
block.   These captured law enforcement blocks would be used as authenticators,
such as in a manually keyed encryption system.  Fending this off would require
escalation in examining the protocols and blocks in the transmission.
The M code stream  might be independently attacked based on knowledge of
clipper chip protocols as revealed plaintext.  This could be invalidated
by changing the temporal and or spatial relationship of the clipper M stream
and the actual transmitted stream, under the control of a secure key
generator synchronized between endpoints.
The useful life time of captured law enforcement blocks might be limited
based on hostile forces using them as targets following transmission
interception.  You would need a large number of them, but, hey there's
supposed to be millions of these things, right?  Adding time stamps to
the encrypted law enforcement block is probably impractical, who wants
an encryption chip with a real time clock?
*****************************************************************************
The entire idea of the law enforcement block can be invalidated.
From: koontzd@phobos.lrmsc.loral.com (David Koontz )
Subject: Re: Will FEDs troll for mutilated law enforcement blocks?
Organization: Loral Rolm Mil-Spec Computers
Lines: 43
The M code stream  might be independently attacked based on knowledge of
clipper chip protocols as revealed plaintext.  This could be invalidated
by changing the temporal and or spatial relationship of the clipper M stream
and the actual transmitted stream, under the control of a secure key
generator synchronized between endpoints.
The useful life time of captured law enforcement blocks might be limited
based on hostile forces using them as targets following transmission
interception.  You would need a large number of them, but, hey there's
supposed to be millions of these things, right?  Adding time stamps to
the encrypted law enforcement block is probably impractical, who wants
an encryption chip with a real time clock?
*****************************************************************************
The entire idea of the law enforcement block can be invalidated.
I just had the thought, that you could capture your own law enforcement blocks
for session keys K that you will not use in actual transmissions as
the session key authenticators.  The proviso that you don't mind your own
serial number being discovered.
d. denning just sent out further information of a new version of the clipper
chip.	If a hash function were to be embedded in a clipper M transmission
block reflecting the law enforcement block, it better not fall on 64 bit block
boundaries.  If it were a recognizeable datum, you could lie with it too.
I like the randomizer inclusion in the MYK-80.  I remember reading that
Intel had an approved random noise source on silicon, hence the ability
to put it Inside.
You ever think that Mykotronx sounds like one of those made up names of
companies used as fronts for intelligence organizations?
From: tuinstra@signal.ece.clarkson.edu.soe (Dwight Tuinstra)
Subject: political point of attack: Clipper infrastructure
Reply-To: tuinstra@signal.ece.clarkson.edu.soe
Organization: Sun Microsystems, Inc.
Lines: 37
Nntp-Posting-Host: signal.ece.clarkson.edu
My earlier argument that "Clipper will encourage state and local cops
to commit criminal acts" is largely moot, now that we've learned that
the FBI will perform the actual tap.  [It will encourage the *FBI* to
commit (even more) criminal acts, but that's not the point here.]
But this gives another avenue of attack on the Clipper proposal.  When
the EFF/ACLU/CPSR FOIA requests are made, they should ask for details
on the bureaucratic and equipment infrastructure that is proposed (or
even already budgeted) for the FBI to service tapping requests -- for now
and the projected future.
From these figures, estimate the number of Clipper-tap requests the FBI
is expecting.  Publish this figure.  Compare it on a per-capita basis
with the amount of tapping now known or suspected.
Also estimate how expensive it would be for the FBI to install more
Clipper-tapping stations, and how rapidly they could be built and
installed ... ie, get the "plus or minus" epsilon for the near future.
Might be a mite disturbing for J. Q. Public to know these things.
And despite all the technical details [BTW, thanks to those who've been
providing them!], we still don't know
1) how the tapping requests will be transmitted and authenticated (though
it isn't too hard to guess a good scheme).
2) how the results will be securely transmitted (Fed Ex the audio tapes?)
3) how privacy will be re-established when an investigation is complete.
+========================================================================+
|  dwight tuinstra             best:  tuinstra@sandman.ece.clarkson.edu  |
|                         tolerable:  tuinstrd@craft.camp.clarkson.edu   |
|                                                                        |
|        "Homo sapiens: planetary cancer??  ...  News at six"            |
+========================================================================+
From: smb@research.att.com (Steven Bellovin)
Subject: Re: Clipper will corrupt cops (was WH proposal from Police point of view)
Organization: AT&T Bell Laboratories
Lines: 65
In article <1993Apr21.041033.16550@news.clarkson.edu>, tuinstra@signal.ece.clarkson.edu.soe (Dwight Tuinstra) writes:
> The clear implication is that there are "legal" authorizations other
> than a court order.  Just how leaky are these?
I don't have the wiretap statute handy.  But here's what the law says
on pen registers.  This is all from Title 18 of the U.S. Code.  Note
how vague S. 3125(a)(1)(B) is....  I haven't had a chance to check
out 50 U.S.C. 1801 yet.
----
18 USC  S. 3121 Pen Registers (as of 4/93)
S. 3121. General prohibition on  pen register  and trap and trace device
use; exception
(a) In general. Except as provided in this section, no person may
install or use a  pen register  or a trap and trace device without first
obtaining a court order under section 3123 of this title or under the
Foreign Intelligence Surveillance Act of 1978 (50 U.S.C. 1801 et seq.).
.....
S. 3125.  Emergency  pen register  and trap and trace device
installation
(a) Notwithstanding any other provision of this chapter , any
investigative or law enforcement officer, specially designated by the
Attorney General, the Deputy Attorney General, the Associate Attorney
General, any Assistant Attorney General, any acting Assistant Attorney
General, or any Deputy Assistant Attorney General, or by the principal
prosecuting attorney of any State or subdivision thereof acting pursuant
to a statute of that State, who reasonably determines that--
(1) an emergency situation exists that involves--
(A) immediate danger of death or serious bodily injury to any person;
or
(B) conspiratorial activities characteristic of organized crime,
that requires the installation and use of a  pen register  or a trap
and trace device before an order authorizing such installation and use
can, with due diligence, be obtained, and
(2) there are grounds upon which an order could be entered under this
chapter to authorize such installation and use "may have installed and
use a  pen register  or trap and trace device if, within forty-eight
hours after the installation has occurred, or begins to occur, an order
approving the installation or use is issued in accordance with section
3123 of this title."
(b) In the absence of an authorizing order, such use shall
immediately terminate when the information sought is obtained, when the
application for the order is denied or when forty-eight hours have
lapsed since the installation of the  pen register  or trap and trace
device, whichever is earlier.
(c) The knowing installation or use by any investigative or law
enforcement officer of a  pen register  or trap and trace device
pursuant to subsection (a) without application for the authorizing order
within forty-eight hours of the installation shall constitute a
violation of this chapter.
From: smb@research.att.com (Steven Bellovin)
Subject: Re: Clipper considered harmful
Distribution: inet
Organization: AT&T Bell Laboratories
Lines: 19
In article <1r24us$oeh@agate.berkeley.edu>, shirriff@sprite.berkeley.edu (Ken Shirriff) writes:
> Imagine archiving all pay-phone conversations, so if someone turns out
> to be a drug dealer, you can listen to all their past drug deals.  And
> archive calls to/from suspected Mafia members, potential terrorists,
> radicals, etc.  Imagine the convenience for the police of being able to
> get a warrant now and listening to all the calls the World Trade Center
> bombers made in the past year.
>
> Since archiving would be such a powerful tool and so easy to do, why
> wouldn't it happen?
Apart from the storage and search requirements, because the evidence
is inadmissible:  wiretaps require a warrant.  And as soon as one
such case comes to light, all previous cases are likely to be discovered,
and thrown out.  There was an article in the NY Times a few months ago
about how many convictions in the state might be invalidated because
they relied on pen registers -- and the Court of Appeals ruled that
pen registers were equivalent to wiretaps, and hence required warrants
under New York law.
From: eab@msc.edu (Edward Bertsch)
Subject: Re: I have seen the lobby, and it is us
Organization: Minnesota Supercomputer Center, Minneapolis, MN
Lines: 18
I agree that notifying your elected officials of your feelings on this
(and any other, for that matter) issue is the way to go.  And by the
way, the phone #s on the list posted the other day were all in Washington
D.C.  --  For most of you, your elected officials will also maintain
a local office in your area code.
When I 'manage' my elected officials, I use their local office #'s
exclusively, and my fax modem and windows-print-capture software are
my tool of choice.  They see my words as I have stated them, rather
than a summary as they would if I called in /voice/ and left a
comment with the office staff.
--
Edward A. Bertsch (eab@msc.edu)   Minnesota Supercomputer Center, Inc.
Operations/User Services          1200 Washington Avenue South
(612) 626-1888 work               Minneapolis, Minnesota  55415
(612) 645-0168 voice mail         [DISCLAIMER: MY OPINIONS; NOT MSCI'S]
From: Marc VanHeyningen <mvanheyn@cs.indiana.edu>
Subject: Re: freely distributable public key cryptography c++ code:  where?
Organization: Computer Science Dept, Indiana University
Lines: 43
Thus said ee92jks@brunel.ac.uk (Jonathan K Saville):
>D. Wigglesworth (smhanaes@gpu.utcc.utoronto.ca) wrote:
>
>: Do you know of any freely distributable c++ (or c) code for public
>: key cryptography (such as RSA)?
>
>: I've tried various archie searches to no avail.
>
>Have you heard of PGP? I assume from your post that you have not. PGP 2.2
>is a freeware RSA encryption program which includes digital signatures and
>comprehensive key management facilities. Most sites also keep the source code.
>A growing number of people are using this excellent software to encrypt (to
>a very high standard) their email and data. Get it before Clinton outlaws it.
>
>Two of the many sites are:
>      rsa.com     /pub/pgp
>      soda.berkeley.edu      /pub/cypherpunks/pgp
PGP is not available on the archive site rsa.com.  If it were, it
would be highly amusing, since rsa.com (actually Public Key Partners,
but it's the same entity) is the organization holding the patents
which they claim are violated if you actually "make, use or sell" PGP.
I believe those patents also apply in Canada, but I'm not a patent
lawyer or anything.
There is no such thing as freely redistributable code for RSA which
can be used in North America without legal entanglements.  You may
wish to consider RSAREF, however, which *is* available from the FTP
site rsa.com in /rsaref but probably doesn't meet your definition of
"freely redistributable" (it's readily available in source, in C, and
does RSA, MD5, etc. and comes with a license allowing noncommercial
use.  Like any other strong crypto software, it's not exportable
legally.  It can be modified with permission from RSADSI, which a
number of people have received in the past.)  For reasons that aren't
entirely clear to me, RSA says that only U.S. people should take
RSAREF from its server, although there aren't ITAR issues regarding
Canada.  The RIPEM distribution site (ripem.msu.edu) has RSAREF in its
distribution, and is OK for Canadians.
--
Marc VanHeyningen   mvanheyn@cs.indiana.edu   MIME & RIPEM accepted
"Barney the Dinosaur is simply Rush Limbaugh in a Dinosaur Suit."  - Lost Boy
From: caronni@nessie.cs.id.ethz.ch (Germano Caronni)
Subject: Some Questions (was: REVISED SUMMARY)
Organization: Swiss Federal Institute of Technology (ETH), Zurich, CH
Lines: 90
> Here is a revised version of my summary that corrects some errors and
> provides some additional information and explanation.
Thank you very much. After reading the text some distinct questions
arised to me, which I guess will also be asked by other people. Perhaps
would it be interesting to find an answer to these questions ?
>                      THE CLIPPER CHIP: A TECHNICAL SUMMARY
>    N, a 30-bit serial number (this length is subject to change)
shorter or longer ?
> Once the session key K is established, the Clipper Chip is used to
> encrypt the conversation or message stream M (digitized voice).  The
> telephone security device feeds K and M into the chip to produce two
> values:
>    E[M; K], the encrypted message stream, and
>    E[E[K; U] + N; F], a law enforcement field ,
> which are transmitted over the telephone line.  The law enforcement
> field thus contains the session key K encrypted under the unit key U
> concatenated with the serial number N, all encrypted under the family
> key F.  The law enforcement field is decrypted by law enforcement after
> an authorized wiretap has been installed.
First question: When will the LawEnforcmentField be transmitted, and how
does the remote Clipper Chip handle it? Is it transmitted periodically
in the stream of encrypted blocks, or just at the beginning ? Does the
phone at the other side discard those packets via a protocol whatsoever,
or tries it to turn them into voice-output ? (Which would not be disturbing)
> At the beginning of a session, a trusted agent from each of the two key
> escrow agencies enters the vault.  Agent 1 enters a secret, random
> 80-bit value S1 into the laptop and agent 2 enters a secret, random
> 80-bit value S2. These random values serve as seeds to generate unit
> keys for a sequence of serial numbers.  Thus, the unit keys are a
> function of 160 secret, random bits, where each agent knows only 80.
Second question: Why!?!? Why is such a strange procedure used, and not
a real RNG ? This turns those S1,S2 in a kind of bottleneck for system-
security.
> When law enforcement has been authorized to tap an encrypted line, they
> will first take the warrant to the service provider in order to get
> access to the communications line.  Let us assume that the tap is in
> place and that they have determined that the line is encrypted with the
> Clipper Chip.  The law enforcement field is first decrypted with the
> family key F, giving E[K; U] + N.  Documentation certifying that a tap
> has been authorized for the party associated with serial number N is
> then sent (e.g., via secure FAX) to each of the key escrow agents, who
> return (e.g., also via secure FAX) U1 and U2.  U1 and U2 are XORed
> together to produce the unit key U, and E[K; U] is decrypted to get the
> session key K.  Finally the message stream is decrypted.  All this will
> be accomplished through a special black box decoder.
So no (technical) provision will be taken to place a 'timeout' on these
warrants? This would be a unique possibility to realize such a technical
restriction, by letting the escrow-agencies perform the decoding of the
session key. Just take modem-lines instead of secure fax. Is this such
a bad idea ?
> A successor to the Clipper Chip, called "Capstone" by the government
> and "MYK-80" by Mykotronx, has already been developed.  It will include
> the Skipjack algorithm, the Digital Signature Standard (DSS), the
> Secure Hash Algorithm (SHA), a method of key exchange, a fast
> exponentiator, and a randomizer.  A prototoype will be available for
> testing on April 22, and the chips are expected to be ready for
> delivery in June or July.
Wow! (How does the randomizer work?) Are the SHA (and Key exchange) secret,
or publicly known ? Key-Exchange is DH, I guess ?
It seems that those who are opposed to this chip shall have a tough time,
your government realy means to act. :-(
Friendly greetings,
Germano Caronni
--
Instruments register only through things they're designed to register.
Space still contains infinite unknowns.
PGP-Key-ID:341027
Germano Caronni caronni@nessie.cs.id.ethz.ch   FD560CCF586F3DA747EA3C94DD01720F
From: holland@CS.ColoState.EDU (douglas craig holland)
Subject: Re: Screw the people, crypto is for hard-core hackers & spooks only
Nntp-Posting-Host: beethoven.cs.colostate.edu
Organization: Colorado State University, Computer Science Department
Lines: 42
In article <1r47l1INN8gq@senator-bedfellow.MIT.EDU> jfc@athena.mit.edu (John F Carr) writes:
>
>In most cases information you come by properly is yours to use as you wish,
>but there are certainly exceptions.  If you write a paper which includes
>sufficiently detailed information on how to build a nuclear weapon, it is
>classified.  As I understand the law, nuclear weapons design is
>_automatically_ classified even if you do the work yourself.  I believe you
>are then not allowed to read your own paper.
>
Hate to mess up your point, but it is incredibly easy to learn how
to make a nuclear weapon.  The hard part is getting the radioactives to
put in it.  Have you ever read Tom Clancy's _The Sum of All Fears_?  It
describes in great detail how a Palestinian terrorist group constructed a
nuclear bomb using stolen (actually found) plutonium, with some help from
an East German nuclear physicist.  For some non fiction, read Tom Clancy's
article _Five Minutes Till Midnight_.  It shows how a terrorist group could
construct a nuke using Neptunium, a low grade radioactive waste product
dumped in toxic waste sites and forgotten about.  He also claims information
on constructing a nuke is easily found in any large library.  Sounds
kind of scary, doesn't it? :-(
>A less serious example: if you tell drivers about a speed trap they are
>about to run into, you can be fined, even though you might argue that you
>broke no law when you discovered the location of the policeman.  The charge
>is interfering with a police officer, which is quite similar what you would
>be doing by reverse engineering the Clipper chip.
>
>Don't tell me that you think this violates the Constitution -- find some
>court cases which have struck down such laws.  Many people would not be
>comforted by the fact that the government violated their rights when it
>imprisoned them.
>
Don't know whether you could get busted for warning of a speedtrap.
Doug Holland
--
----------------------------------------------------------------------------
|  Doug Holland                | Anyone who tries to take away my freedom  |
|  holland@cs.colostate.edu    | of speech will have to pry it from my     |
|  PGP key available by E-mail | cold, dead lips!!                         |
From: brad@optilink.COM (Brad Yearwood)
Subject: Re: Would "clipper" make a good cover for other encryption method?
Organization: Optilink Corporation, Petaluma, CA
Lines: 19
In article <strnlghtC5t42t.J9B@netcom.com>, strnlght@netcom.com (David Sternlight) writes:
>
> Chances are the government has thought of this, and "just anyone" won't be
> permitted access to enough of the internals to make a "fake" clipper chip.
> Chances are that the government has classified some details of the internals
> at a very high level, and manufacturers are required to observe security
> safeguards and clearances corresponding to that level.
Assume in this case the usual canard-adversary of narcotraficantes.  They
probably have more cash than the KGB did, and they're probably more generous
at handing it out.  It will be easier than ever to find or cultivate Walkers
and Pollards for the keys, and it will be easy enough to find someone to
reverse-engineer the chip (unless the tamper proofing is damned clever and
effective).
Brad Yearwood     brad@optilink.com     {uunet, pyramid}!optilink!brad
Petaluma, CA
From: djb@silverton.berkeley.edu (D. J. Bernstein)
Subject: Re: Off the shelf cheap DES keyseach machine
Organization: IR
Lines: 12
In article <1993Apr21.132318.16981@ulysses.att.com> smb@research.att.com (Steven Bellovin) writes:
> And key size is one of the things that can be
> verified externally.
Gee. Say they feed the 80-bit key through Snefru-8 and take the first 60
bits of the result, then use those 60 bits as the real key. How do you
figure out that each key is one of 2^20 ``equal'' keys? You can try a
birthday attack, but if the key can be changed only once a second then
you will need several lifetimes to get reliable statistics. Somehow I
don't think you could catch the NSA at this sort of skulduggery.
---Dan
From: bear@tigger.cs.Colorado.EDU (Bear Giles)
Subject: Re: The [secret] source of that announcement
Nntp-Posting-Host: tigger.cs.colorado.edu
Organization: National Oceanic & Atmospheric Adminstration / Boulder Labs
Distribution: inet
Lines: 33
>Andrew Molitor (amolitor@nmsu.edu) wrote:
>:
>: 	1) Monitor my phonecalls.
>: 	2) Monitor usenet.
They may collect the data, but making sense of it is another matter.
On sci.crypt I'm a graduate CS major (with strong math background) and
experienced programmer taking a cryptology course.  (<< keyword for
alleged NSA filters).
On sci.skeptic I'm an ex-physics major who's a new-age flake, talking
about silly things like how a person's expectations colors what he
sees.
On talk.religion.newage I'm a physics geek who enjoys squashing
interesting idea with WASP science, although I do write occasional
posts showing a minimal knowledge of Zen, mythology, etc.
I could go on, but I'm sure you see my point.  I'm a single person,
but I react differently on different groups (admittedly, in part
because I'm a contrarian you always shouts "but, on the other hand...").
On top of that, I _loath_ certainty and have taken public positions
in the past for no reason other than to challenge "conventional wisdom".
I wish them luck in figuring out who "I" am based on that information.
(They can probably figure out I'm liberal, with a technical degree
but humanistic interests, from a common thread throughout my posts.
But that describes a fair portion of the users of Internet).
--
Bear Giles
bear@cs.colorado.edu/fsl.noaa.gov
From: wcs@anchor.ho.att.com (Bill Stewart +1-908-949-0705)
Subject: Re: An Open Letter to Mr. Clinton
Organization: Sorcerer's Apprentice Cleaning Services
In-Reply-To: strnlght@netcom.com's message of Sat, 17 Apr 1993 04:41:19 GMT
Nntp-Posting-Host: rainier.ho.att.com
Lines: 26
In article <strnlghtC5M2Cv.8Hx@netcom.com> strnlght@netcom.com (David Sternlight) writes:
Here's a simple way to convert the Clipper proposal to an unexceptionable
one: Make it voluntary.
That is--you get high quality secure NSA classified technology if you agree
to escrow your key. Otherwise you are on your own.
That's the disturbing part - use of other products IS voluntary, for now,
and the press releases talk about the White House's unwillingness to
decide that citizens have a right to good commercial crypto gear,
and about how commercial alternatives will be permitted as long as
they provide key escrow services.  That's a clear implication that
they're considering banning alternatives.
Additionally, use of real alternatives ISN'T totally legal -
you're not allowed to export really good crypto equipment except to
the government's friends (e.g. the Australian government)
you can only export even BAD crypto equipment with their permission,
and the regulators who control the cellular telephone companies make
sure there are only two competitors, so Joe's Garage Cellular can't
start offering a secure service.
--
#				Pray for peace;      Bill
# Bill Stewart 1-908-949-0705 wcs@anchor.att.com AT&T Bell Labs 4M312 Holmdel NJ
#	              No, I'm *from* New Jersey, I only *work* in cyberspace....
# White House Commect Line 1-202-456-1111  fax 1-202-456-2461
From: wcs@anchor.ho.att.com (Bill Stewart +1-908-949-0705)
Subject: Re: Clipper considered harmful
Organization: Sorcerer's Apprentice Cleaning Services
Distribution: inet
In-Reply-To: shirriff@sprite.berkeley.edu's message of 21 Apr 1993 00:36:44 GMT
Nntp-Posting-Host: rainier.ho.att.com
Lines: 24
In article <1r24us$oeh@agate.berkeley.edu> shirriff@sprite.berkeley.edu (Ken Shirriff) writes:
In article <15469@optilink.COM> brad@optilink.COM (Brad Yearwood) writes:
>Finally, because there is essentially no possibility of intercepting in
>realtime the scrutable content of communications between stolen instruments,
>there will exist strong motivation to record and archive _all_ communications
>in the network for ex-post-facto scrutiny (once some criminal act is
>discovered, and the instruments involved have been identified).
"All" is a *very* big number.  The AT&T Long Distance network has
around 20,000 T3 trunks (45 Mbit/sec), which is on the order of 10**12 bits/sec.
That doesn't even count the amount of traffic in the LOCAL phone companies,
or our long-distance competitors.  It's about 200 Exabytes tapes / second,
which is pretty large even for the NSA :-)
On the other hand, I can easily see them recording the traffic for
"interesting" people, such as dissidents, suspected criminals,
foreign telephone calls, and anybody noticed using encryption.
As Ken Shiriff speculates, recording encrypted traffic will probably
be judged not to be an invasion of privacy pretty soon ....
--
#				Pray for peace;      Bill
# Bill Stewart 1-908-949-0705 wcs@anchor.att.com AT&T Bell Labs 4M312 Holmdel NJ
#	              No, I'm *from* New Jersey, I only *work* in cyberspace....
# White House Commect Line 1-202-456-1111  fax 1-202-456-2461
From: andersom@spot.Colorado.EDU (Marc Anderson)
Subject: **Sorry folks** (read this)
Nntp-Posting-Host: spot.colorado.edu
Organization: University of Colorado, Boulder
Distribution: na
Lines: 32
In article <1993Apr21.001707.9999@ucsu.Colorado.EDU> andersom@spot.Colorado.EDU (Marc Anderson) writes:
[...]
>
>(the date I have for this is 1-26-93)
>
>note Clinton's statements about encryption in the 3rd paragraph..  I guess
>this statement doesen't contradict what you said, though.
>
>--- cut here ---
>
>        WASHINGTON (UPI) -- The War on Drugs is about to get a fresh
>start, President Clinton told delegates to the National Federation
>of Police Commisioners convention in Washington.
>        In the first speech on the drug issue since his innaugural,
>Clinton said that his planned escalation of the Drug War ``would make
>everything so far seem so half-hearted that for all practical
[...]
I just found out from my source that this article was a joke.  Heh heh..
It seemed pretty damn convincing to me from the start -- I just didn't
notice the smiley at the end of the article, and there were a few other
hints which I should of caught.
Anyway -- I guess this 'joke' did turn out to resemble Clinton's true
feelings at least to some extent.
Sorry about that...
-marc
andersom@spot.colorado.edu
From: anthonyf@microsoft.com (Anthony Francisco)
Subject: Re: Clipper and Ranting Libertarians
Organization: Microsoft Corp.
Keywords: clipper clinton rant rave libertarians
Distribution: usa
Lines: 11
Just a little nitpicking. Wasn't it the government that required
a standard railway gauge ? Didn't that improve things ?
Please don't misunderstand. I'm utter suspicious of this Clipper
chip. Why hold the design TOP SECRET ? Was this a work around the
law that says that any discoveries made by people working for the
government is public domain. ( e.g. NIH Class Library, etc. )
DES has its designs published all over the place and it is considered
fairly strong ( although could be stronger ).
- Ants
From: steve-b@access.digex.com (Steve Brinich)
Subject: Fear, Uncertainty, Doubt
Organization: Express Access Online Communications, Greenbelt, MD USA
Lines: 10
NNTP-Posting-Host: access.digex.net
I suspect that the decisive element in the political battle will be the
FUD (Fear, Uncertainty, Doubt) factor.
If the people who would be end users of the Cripple Chip hear of the whole
debate only vaguely -- the government says it's solid; other people in the
field say it's Swiss cheese -- the balance of doubt could shift against the
Feds.  Any attempt to limit other forms of encryption could then be presented
as the government covering its own butt by protecting its poor product from
superior competition.
Comments?
Subject: Re: How large are commercial keys?
From: pgut1@cs.aukuni.ac.nz (Peter Gutmann)
Organization: Computer Science Dept. University of Auckland
Lines: 17
In <1993Apr20.182038.12009@ee.eng.ohio-state.edu> butzerd@maumee.eng.ohio-state.edu (Dane C. Butzer) writes:
>What are the typical sizes for keys for commercial secret key algorithms?
>I know DES is 56 bits ("tripple DES" is 112 bits) and IDEA is 128 bits.  Is
>there anything made in the US that has 128 bit keys?  Anything anywhere
>that has larger keys?  I've heard that RC2 can be scaled to arbitrarily
>large keys, but is this actually implemented anywhere?
My MDC cipher (which uses any one-way hash function as a CFB-mode stream
cipher, the current implementation uses MD5) uses a key of up to 2048 bits
(that is, you can use a 1-bit key if you want and copy it over the entire
2048-bit range, or you can use the entire 2048 bits).  Runtime is
independant of key size, the system runs slightly slower than MD5 itself.
I presume RC2 and RC4 use a similar system (or possibly they just hash an
arbitrary-length key down to n bits, maybe 128, using something like MD5).
Peter.
From: rita@eff.org (Rita Marie Rouvalis)
Subject: Re: **Sorry folks** (read this)
Originator: rita@eff.org
Nntp-Posting-Host: eff.org
Organization: Enormes_Rebajas_Online
Distribution: na
Lines: 15
In article <1993Apr22.014646.28445@ucsu.Colorado.EDU> andersom@spot.Colorado.EDU (Marc Anderson) writes:
>I just found out from my source that this article was a joke.  Heh heh..
>It seemed pretty damn convincing to me from the start -- I just didn't
>notice the smiley at the end of the article, and there were a few other
>hints which I should of caught.
People took this article seriously?  I mean, I know it's the
Net and all, but the prankster didn't even have Clinton's sound-bites
right.
--
Rita Rouvalis
rita@village.com
Subject: Re: Once tapped, your code is no good any more.
From: pgut1@cs.aukuni.ac.nz (Peter Gutmann)
Organization: Computer Science Dept. University of Auckland
Lines: 48
In <1993Apr21.001707.9999@ucsu.Colorado.EDU> andersom@spot.Colorado.EDU (Marc Anderson) writes:
>(the date I have for this is 1-26-93)
>note Clinton's statements about encryption in the 3rd paragraph..  I guess
>this statement doesen't contradict what you said, though.
>--- cut here ---
>        WASHINGTON (UPI) -- The War on Drugs is about to get a fresh
>start, President Clinton told delegates to the National Federation
>of Police Commisioners convention in Washington.
>        In the first speech on the drug issue since his innaugural,
>Clinton said that his planned escalation of the Drug War ``would make
>everything so far seem so half-hearted that for all practical
>purposes this war is only beginning now.'' He repeatedly emphasized
>his view that ``regardless of what has been tried, or who has tried
>it, or how long they've been trying it, this is Day One to me.''
>The audience at the convention, whose theme is ``How do we spell
>fiscal relief?  F-O-R-F-E-I-T-U-R-E,'' interrupted Clinton frequently
>with applause.
>        Clinton's program, presented in the speech, follows the
>outline given in his campaign position papers: a cabinet-level Drug
>Czar and ``boot camps'' for first-time youthful offenders.  He did,
>however, cover in more detail his plans for improved enforcement
>methods.  ``This year's crime bill will have teeth, not bare gums,''
>Clinton said.  In particular, his administration will place strict
>controls on data formats and protocols, and require the registration
>of so-called ``cryptographic keys,'' in the hope of denying drug
>dealers the ability to communicate in secret.  Clinton said the
>approach could be used for crackdowns on other forms of underground
>economic activity, such as ``the deficit-causing tax evaders who
>live in luxury at the expense of our grandchildren.''
>        Clinton expressed optimism that the drug war can be won
>``because even though not everyone voted for Bill Clinton last
>November, everyone did vote for a candidate who shares my sense of
>urgency about fighting the drug menace.  The advocates of
>legalization -- the advocates of surrender -- may be very good at
>making noise,'' Clinton said.  ``But when the American people cast
>their ballots, it only proved what I knew all along -- that the
>advocates of surrender are nothing more than a microscopic fringe.''
Just doing a quick reality check here - is this for real or did someone
invent it to provoke a reaction from people?  It sounds more like the
sort of thing you'd have heard, suitably rephrased, from the leader of a
certain German political party in the 1930's....
Peter.
From: rlglende@netcom.com (Robert Lewis Glendenning)
Subject: Re: Estimating Wiretap Costs/Benefits
Organization: Netcom - Online Communication Services (408 241-9760 guest)
Lines: 13
I am most embarassed that my irrate, intemperate post is still
circulating.
I have been chided by experts for my behavior.  I now agree with
all of them, although some were no more restrained in their
speech than I was 8)
I have apologized to Robin Hanson.
Lew
--
Lew Glendenning		rlglende@netcom.com
"Perspective is worth 80 IQ points."	Niels Bohr (or somebody like that).
From: duck@nuustak.csir.co.za (Paul Ducklin)
Subject: Re: Do we need the clipper for cheap security?
Organization: CSIR, South AFrica
Lines: 27
NNTP-Posting-Host: nuustak.csir.co.za
X-Disclaimer: None of the opions expressed herein are the official
X-Disclaimer: opinions of the CSIR or any of its subsidiaries.
X-Disclaimer: **  So don't freak out at _us_ about anything  **
gtoal@gtoal.com (Graham Toal) writes:
>Can someone tell me if hardware compression is or is not needed to run
>digital speech down 14.4K?  I think it is; I've heard it's not.  Lets
>say 8 bit samples.  Would *raw* data at the corresponding sampling rate
>be usable?  If not, how fancy does the compression need to be?
It's all easy with a DSP. The Olivetti Quaderno, for example [*great* 1kg
subnotebook/palmtop PC -- sorry for the plug, folks, but Olivetti don't
seem to be doing a good job marketing it themselves :-)] includes sound
digitisation hardware; they provide vocoders for their DSP which produce
varous bit-rates. There's one which gives pretty acceptable voice
quality at 13Kbit/sec, just right for a V.32bis modem.
Their DSP can play and record at the same time, too -- so you wouldn't
need to play "two-way-radio". You can also download code to the DSP
subunit, though you'd need a software development kit for the DSP in
question [dunno which it is...] if you wanted to produce your own
vocoder for, say, V.32 speeds.
Paul
/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\  Paul Ducklin                         duck@nuustak.csir.co.za  /
/  CSIR Computer Virus Lab + Box 395 + Pretoria + 0001 S Africa  \
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
From: TSOS@uni-duesseldorf.de (Detlef Lannert)
Subject: Re: Facinating facts: 30 bit serial number, possibly fixed S1 and S2
Organization: Universitaetsrechenzentrum, Heinrich-Heine-Universitaet, Duesseldorf
Lines: 40
NNTP-Posting-Host: lannert.rz.uni-duesseldorf.de
In article <PMETZGER.93Apr20065402@snark.shearson.com> pmetzger@snark.shearson.com (Perry E. Metzger) writes:
>Hmmm. We must assume that generating the unit key U from the serial
>number N rather than generating it from a randomly selected U1 and U2
>is an intentional way of assuring a "fail safe" for the government --
>U is completedly determined given S1, S2 and N.
[...]
>If S1 and S2 do not change, even if they remain secret I wonder if
>they can somehow be back-derived given enough unit key/serial number
>pairs. [...]
Maybe 300 such pairs suffice to reconstruct S1 and S2? By such a back-
door (in the encryption algorithm perhaps) it would be possible (for
the manufacturer) to get the keys of all chips that were programmed in
one session. This would not, btw, enable anybody else to retrieve the
keys in the same way because they'll never get a bunch of 300 (N,U)
pairs with identical S1 and S2. (Note that these have to be constant
for the whole batch by the very nature of the procedure, i.e., they
have to be typed in manually by the `random number supplying agents'!)
And I was wondering why they'll always do 300 chips in one session ...
Since the procedure described by Ms Denning imposes high costs on the
production of every chip (at least three persons for one hour each,
plus the cost of a laptop finally blown to pieces in a spectacular,
Hollywood-like bonfire; add travelling expenses, drinks and lighting,
divide the sum by 300) there won't be a larger demand -- not from the
private sector anyway.
And let me mention one other thought that certainly has occurred to all
the notoriously paranoid people in this group before: Who is going to
verify that _no_ interested party will perform tempest attacks on the
vault??
Where there's so much smoke and mirrors -- there can't be a nice, honest
fire but something really worth hiding ...
--
Detlef Lannert       DC3EK       E-Mail: tsos@rz.uni-duesseldorf.de
PGP 2.2 key via server or finger lannert@clio.rz.uni-duesseldorf.de
"I am Psmith." - "Oh, you're Smith, are you?" - "With a preliminary
P. Which, however, is not sounded."                   P.G.Wodehouse
From: smb@research.att.com (Steven Bellovin)
Subject: Re: Off the shelf cheap DES keyseach machine
Organization: AT&T Bell Laboratories
Lines: 16
In article <7020.Apr2207.05.3993@silverton.berkeley.edu>, djb@silverton.berkeley.edu (D. J. Bernstein) writes:
> In article <1993Apr21.132318.16981@ulysses.att.com> smb@research.att.com (Steven Bellovin) writes:
> > And key size is one of the things that can be
> > verified externally.
>
> Gee. Say they feed the 80-bit key through Snefru-8 and take the first 60
> bits of the result, then use those 60 bits as the real key. How do you
> figure out that each key is one of 2^20 ``equal'' keys? You can try a
> birthday attack, but if the key can be changed only once a second then
> you will need several lifetimes to get reliable statistics.
You're right, and I retract the suggestion.  Still, I wonder.  That
there are only 60 bits of key information should, in principle, be
detectable.  Maybe some variant of the tests Rivest et al. did to
demonstrate that DES was probably not a group?  It should make an
interesting paper -- a black-box analysis of a cryptosystem.
From: whughes@lonestar.utsa.edu (William W. Hughes)
Subject: Re: Tempest
Nntp-Posting-Host: lonestar.utsa.edu
Organization: University of Texas at San Antonio
Distribution: na
Lines: 32
In article <1993Apr22.105915.5584@infodev.cam.ac.uk> rja14@cl.cam.ac.uk
(Ross Anderson) writes:
>res@colnet.cmhnet.org (Rob Stampfli) writes:
>> Wouldn't a a second monitor of similar type scrolling gibberish and adjacent
>> to the one being used provide reasonable resistance to tempest attacks?
>We've got a tempest receiver in the lab here, and there's no difficulty in
>picking up individual monitors. Their engineering tolerances are slack enough
>that they tend to radiate on different frequencies. Even where they overlap, you
>can discriminate because they have different line synch frequencies - you can
>lock in on one and average the others out.
>
>The signals are weird in any case, with varying polarisations and all sorts
>of interactions with the building. Just moving a folded dipole around is also
>highly effective as a (randomised) means of switching from one monitor to
>another,
>
Hell, just set up a spark jammer, or some other _very_ electrically-noisy
device. Or build an active Farrady cage around the room, with a "noise"
signal piped into it. While these measures will not totally mask the
emissions of your equipment, they will provide sufficient interference to
make remote monitoring a chancy proposition, at best. There is, of course,
the consideration that these measures may (and almost cretainly will)
cause a certain amount of interference in your own systems. It's a matter
of balancing security versus convenience.
BTW, I'm an ex-Air Force Telecommunications Systems Control Supervisor and
Telecommunications/Cryptographic Equipment Technician.
--
REMEMBER WACO!
Who will the government decide to murder next? Maybe you?
[Opinions are mine; I don't care if you blame the University or the State.]
From: pom@anke.imsd.uni-mainz.DE (Prof. Dr. Klaus Pommerening)
Subject: DES: init vector as additional key?
Keywords: DES, CBC, CFB, key search
Nntp-Posting-Host: anke.imsd.uni-mainz.de
Organization: Johannes Gutenberg Universitaet Mainz
Lines: 15
The recent discussion in this news group suggests that a key search attack
against DES is quite feasible now. But normally DES is applied in CBC or CFB
mode where one chooses a random init vector of 8 bytes. Questions:
- Makes it sense to handle the init vector as an additional key? Then we have
a 56 + 64 = 120 bit key.
- If yes: Is anything known about the security of this key scheme? Can we
break it faster than by exhaustive search through the 120 bit key space?
--
Klaus Pommerening
Institut fuer Medizinische Statistik und Dokumentation
der Johannes-Gutenberg-Universitaet
Obere Zahlbacher Strasse 69, W-6500 Mainz, Germany
From: lfoard@hopper.Virginia.EDU (Lawrence C. Foard)
Subject: Re: Once tapped, your code is no good any more.
Organization: ITC/UVA Community Access UNIX/Internet Project
Lines: 16
In article <1993Apr22.065357.9667@cs.aukuni.ac.nz> pgut1@cs.aukuni.ac.nz (Peter Gutmann) writes:
[article deleted]
>
>Just doing a quick reality check here - is this for real or did someone
>invent it to provoke a reaction from people?  It sounds more like the
>sort of thing you'd have heard, suitably rephrased, from the leader of a
>certain German political party in the 1930's....
It sounds like a joke (but then the war on drugs has always been a joke...).
--
------          Join the Pythagorean Reform Church!               .
\    /        Repent of your evil irrational numbers             . .
\  /   and bean eating ways. Accept 10 into your heart!        . . .
\/   Call the Pythagorean Reform Church BBS at 508-793-9568  . . . .
From: harryb@phred.UUCP (harry barnett)
Subject: Re: text of White House announcement and Q&As on clipper chip encryption
Reply-To: harryb@phred.UUCP
Organization: Physio-Control
Lines: 48
In article 29778@yuma.ACNS.ColoState.EDU, holland@CS.ColoState.EDU (douglas craig holland) writes:
>In article <1993Apr19.130132.12650@afterlife.ncsc.mil> rlward1@afterlife.ncsc.mil (Robert Ward) writes:
>>In article <bontchev.734981805@fbihh> bontchev@fbihh.informatik.uni-hamburg.de writes:
>>>and since the US constitutions guarantees the right to every American
>>>to bear arms, why is not every American entitled, as a matter of
>>
>>Have you read the applicable part of the Constitution and interpreted it IN
>>CONTEXT?  If not, please do so before posting this misinterpretation again.
>>It refers to the right of the people to organize a militia, not for individuals
>>to carry handguns, grenades, and assault rifles.
>
>Read the Constitution yourself.  The Second Amendment says the right to bear
>arms shall not be infringed, so a well regulated militia may be more easily
>formed.  I have an interpretation of the Second that shows there are no
>qualifications to the right to keep and bear arms.  If you want, I can E-mail
>it to you.  By the way, gun talk belongs in talk.politics.guns.
>							Doug Holland
Mr. Ward, before you start blathering about your skill "interpreting"
the Constitution, it might be helpful to learn to read.  After a review
with a high school English teacher emphasizing participial phrases, you
might start with the Second Amendment, and follow it up with:
97th Congress, 2nd Session, Committee Print, *The Right To Keep and
Bear Arms*, of the Subcomittee on the Constitution of the Committee on
the Judiciary, United States Senate, 97th Congress, Second Session,
February, 1982.  GPO No. 88-618-O
This authoritative, heavily researched and annotated document clearly
turns your "interpretation" into specious claptrap, which is a polite
way of saying utter bullshit.  In spite of your false assertion to the
contrary, the Second Amendment DOES protect the right of the individual
citizen, in his capacity as an individual, to keep and bear arms.
And, Mr. Holland, IMHO, blatantly and harmfully false information,
asserted as fact and globally distributed, deserves globally
distributed rebuttal in the forum in which it is posted.
(And besides, this site doesn't carry t.p.g...:-)
harryb%phred@data-io.com
phred!harryb@data-io.com
-----------------------------------------------------------------------
No free man shall ever be debarred the use of arms.  The strongest
reason for the people to retain the right to keep and bear arms is,
as a last resort, to protect themselves against tyranny in government.
--Thomas Jefferson
-----------------------------------------------------------------------
From: Borut.B.Lavrencic@ijs.si
Subject: Re: The [secret] source of that announcement
Reply-To: Borut.B.Lavrencic@ijs.si
Distribution: inet
Organization: J. Stefan Institute, Lj, Slovenia
Lines: 61
In article <gradyC5unp0.D21@netcom.com>,
grady@netcom.com (1016/2EF221) writes:
> Andrew Molitor (amolitor@nmsu.edu) wrote:
> :
> : 	1) Monitor my phonecalls.
> : 	2) Monitor usenet.
> : 	3) Provide only cryptosystems they can easily crack.
> : 	4) etc etc.
> :
> : 	This is not to say that they *don't*, they might. But you don't
> : know that they do, and you have no evidence that they do, for almost
> : all values of you. It follows, therefore, that for most values of 'you',
> : your claims about the NSA border on paranoia.
> :
> : 	Andrew
.....
.....
.....
>
> Or maybe the Germans should have been a little more 'paranoid' about
> their Engima with respect to Turing and the British.
>
> How about the cracking of the Zimmerman telegram?  Would a little
> more paranoia have helped the Germans here?
>
> Maybe the NSA should have been a little more 'paranoid' about
> Emma Woikin, or Joseph Sidney Petersen, Jr., or  ...
>
> Maybe you want to talk about Macmillan publishers cooperation
> with the CIA and NSA to suppress Yardley's Japanese Diplomatic
> Secrets or even Kahn's The Codebreakers.. paranoia, right?
>
> The most popular cipher systems in captured soviet spies was
> the one-time pad, even with the necessity of keeping incriminating
> evidence about, is known to be the only proven unbreakable system.
> Soviet paranoia, right?
>
> And what do you think the NSA does with its Wullenwebers?  And
> huge Rhombics pointed embassy row?  And their sites near
> satellite uplink and downlink sites?  Duh.
>
.....
> --
> grady@netcom.com  2EF221 / 15 E2 AD D3 D1 C6 F3 FC  58 AC F7 3D 4F 01 1E 2F
>
One case of Slovenian paranoia.
Once upon a time a tried to walk over the (famous) Marathon field, not far away
from Athens. I could not do that mostly becouse the field is now a huge
antenna farm. Probably a Greek COMINT installation, would you agree?
--
Borut B. Lavrencic, D.Sc.     | X.400   :C=si;A=mail;P=ac;O=ijs;S=lavrencic
J. Stefan Institute           | Internet:Borut.B.Lavrencic@ijs.si
University of Ljubljana,      | Phone   :+ 386 1 159 199
SI-61111 Ljubljana, Slovenia  |	    PGP Public Key available on request
DOLGO SMOIS KALIS OVRAZ NIKEI NJIHK OCNOO DKRIL IVSEB IPIKA
From: pdc@dcs.ed.ac.uk (Paul Crowley)
Subject: Re: Do we need the clipper for cheap security?
Reply-To: pdc@dcs.ed.ac.uk (Paul Crowley)
Organization: Edinburgh University
Lines: 12
Quoting pmetzger@snark.shearson.com (Perry E. Metzger) in article <1993Apr21.012011.27470@shearson.com>:
>Whats the difference between a V.32bis modem and a V.32bis modem?
How fast do the fastest modems go?
How far can voice be compressed?
I've seen various assertions about this, but anyone with the
straightforward bits-per-second figures will be my friend forever...
__                                  _____
\/ o\ Paul Crowley   pdc@dcs.ed.ac.uk \\ //
/\__/ Trust me. I know what I'm doing. \X/  Fold a fish for Jesus!
From: pdc@dcs.ed.ac.uk (Paul Crowley)
Subject: Re: Hard drive security for FBI targets
Reply-To: pdc@dcs.ed.ac.uk (Paul Crowley)
Organization: Edinburgh University
Lines: 14
If "I forgot" doesn't have as much credibility as you'd like, consider
this alternative.  Somewhere on the hard disk, duplicated a few times,
keep a 128-bit random number.  When the 128-bit digest of your
passphrase is computed, it is XORred with the random number before being
used as the key for your hard disk.  Writing random junk over the random
numbers makes the hard disk unreadable by anyone.
Now, if you were merely to *claim* that you have written random junk
over the XOR key, no-one would be able to tell whether or not you were
telling the truth.  This is (a) perjury, and (b) vunerable to
rubber-hose cryptography, but otherwise effective.
__                                  _____
\/ o\ Paul Crowley   pdc@dcs.ed.ac.uk \\ //
/\__/ Trust me. I know what I'm doing. \X/  Fold a fish for Jesus!
From: gtf1000@cus.cam.ac.uk (G.T. Falk)
Subject: alt.security.pgp
Nntp-Posting-Host: bootes.cus.cam.ac.uk
Organization: U of Cambridge, England
Lines: 25
-----BEGIN PGP SIGNED MESSAGE-----
Hi all..
Does anyone know of a UNIX utility allowing encrypted telnet sessions using
public-key? I'd like something so that nobody can snoop my password or
session text while I'm logging in remotely over the network.
Thanks
g.
- -------------------------------------------------------------------------
PLEASE REPORT UNSIGNED (HENCE UNAUTHORISED) MESSAGES PURPORTEDLY FROM ME,
SENT AFTER 22/04/93.                                gtf1000@cus.cam.ac.uk
- -------------------------------------------------------------------------
-----BEGIN PGP SIGNATURE-----
Version: 2.2
iQBVAgUBK9ZxMTQRcjh0adt3AQFHrwH9HwBPyWwr+/O+pEocO9glPOZ5odKHynW8
AJIiF6Tsm+YMqBwmVHoLm7bUb4JPybQanpkmz8tdd4tYuinSX68cVg==
=Gw7z
-----END PGP SIGNATURE-----
From: abaum@armltd.uucp (Allen Baum)
Subject: Re: 80-bit keyseach machine
Organization: Advanced RISC Machines Ltd
Lines: 13
jebright@magnus.acs.ohio-state.edu (James R Ebright) writes:
(regarding NSA monitoring of US military code traffic)
>[BTW, folks, NSA wasn't being given the keys.  And the Walker spy case
>shows for some of the systems, the KGB didn't need them either.]
On the contrary- The Walker spy case is one where the KGB was
given keys (as I recall)
--
----------------
Allen J. Baum		Apple Computer		baum@apple.com, abaum@armltd.co.uk
From: pdh@netcom.com (P D H)
Subject: Re: An Open Letter to Mr. Clinton
Organization: NETCOM On-line Communication Services (408 241-9760 guest)
Lines: 105
ld231782@LANCE.ColoState.Edu (L. Detweiler) writes:
>I'm quite astonished, shocked, and appalled at this serious frontal
>assault on emerging American freedoms.  The Clinton administration
>nor any other government agency has any legitimate role whatsoever
>in regulating cryptography. To do so is tantamount to regulating
>`acceptable' speech, and is blatantly unconstitutional. Perhaps we
>should rename this year `1984' in honor of such an illustrious
>proposal.  Let the Crappy Chip live in infamy, and the adminstration
>receive great shame and discredit for this bizarre misadventure.
IMHO, encryption is (also) protected under the SECOND amendment of
the Constitution of the United States.
>I am outraged that my tax money is being used to develop technology
>to restrict my freedoms far beyond reasonable measures.  The U.S.
>government will have my full uncooperation and disobedience on any
>serious threat to my liberties such as this, and I call on everyone
>with an interest in a sensible government to resist and defy this
>proposal.  The administration does not seem to understand that they
>are merely a subservient instrument to implement the will of the
>public, and hence anyone involved in this proposal in this respect is
>wholly negligent and remiss in performing their lawful duty.
I am not surprised that this administration is doing this.
I could have told you so.
>Cryptography is neutral technology. If everybody has strong
>cryptography (including policemen, bureacrats, businessmen,
>housewives, thugs and hoodlums), we have a sustainable
>equilibrium.  Anything less is an unworkable anti-egaltarian
>arrangement, intrinsically antithetical to American freedoms, and
>guaranteed to collapse under its own weight of inherent
>impracticality. We don't need to compromise on issues of freedom.
Privacy has ALWAYS been something that has the effect of restricting
out ability to prosecute criminals.  We are supposed to have the
presumption of innocence.
I have the right to pull the curtains over my windows and close my
door, and the police may not come in.  If I perform a crim in my home,
they will have to find out by means other than simply looking.
Encryption is to my data as the window curtains are to my home.
Simple enough?
>For too long our government has demonstrated itself to be
>increasingly hostile and a serious obstacle to economic vitality
>and protecting Americans.
And yet the people vote for these people because they come out a lie
to them about promising to fix things.
>The administration has to be committed to leaving private
>industries alone, esp. on this issue.  The government has no
>legitimate role in regulating the content of communications.
>Law enforcement agencies must be prepared to forfeit their
>surveillance bludgeon; they are soon and inevitably to be
>disarmed of it.
You mean they might have to go back to actually WORKING to do their job?
Oh heavens.
>No such laws can be constitutionally sound, and this is equivalent
>to a veiled threat, which I don't appreciate.  This kind of
>extortion tends to agitate me and others into radicalism. I will
>trade threats for threats, and violation for violation.
Perhaps the FIRST amendment.  Definitely the SECOND and FIFTH.
>If the administration did say this, it would find itself
>impeached for reckless and outrageous disregard of essential,
>established, entrenched, and explicit constitutional privacy
>guarantees. The administration would have no legal standing
>whatsoever; such an action would be egregiously illegal and
>criminal, and wholly untolerated and disregarded by vast
>segments of the population.
Unfortunately, the vast segments of the population are misinformed.
They just haven't appended -SR to the name of out country, yet.
>This is an outright Dingaling Denning lie.  The two aims of
>privacy and surveillance are intrinsically and fundamentally
>incompatible, and you have to work for the NSA to think otherwise.
>Americans are about to discover ways, through the use of technology,
>to preserve their inalienable but forgotten freedoms that have slowly
>been eroded away by an increasingly distant and unresponsive and
>*unrepresentative* government.
I seriously doubt that the NSA thinks that privacy and surveillance are
compatible.  I doubt of any smart person in any other agency thinks
so, either.  The PROBLEM is that they simply hold PRIVACY to be of no
value at all.
--
| Phil Howard,  pdh@netcom.com,  KA9WGN         Spell protection?  "1(911)A1" |
| Right wing conservative capitalists are out to separate you from your MONEY |
| Left wing liberal do gooders are out to separate you from EVERYTHING ELSE!! |
+-----------------------------------------------------------------------------+
From: jhan@debra.dgbt.doc.ca (Jerry Han)
Subject: Overreacting (was Re: Once tapped, your code is no good any more)
Nntp-Posting-Host: debra.dgbt.doc.ca
Organization: Communications Research Centre, Ottawa
Distribution: na
Lines: 36
In this giant bally-ho over this Clipper chip I noticed a rather
disturbing trend in some of the E-mail and posts I've tossing back and
forth.
Somebody asked me what was wrong about overreacting in cases such as this.
The reason is very simple:  How many people do you want to die in a riot?
In a new Civil War?
Everybody is jumping up and down and screaming about it, and I'm worried
that people are going to reach for their hammers and rifles before their pens
and paper.
Can people work within the system before trying to break it?  Examine your
history books, and find out how many armed revolutions led to Democratic
(or Democratic style) governments.  I think you'll only find one in over
five thousand years of written history.
That's not very good odds.
Somebody once said something like: "Armed Violence is meant only to be
used in response to an armed attack.  It is not meant to be used in
agression.  This is the difference between self-defence and murder."
Let's try to avoid killing things, eh?  There's enough blood shed in the
world, without adding a couple of riots, Civil Wars, etc.
I'm probably overreacting.  But what I've read scared me a lot.  I don't
want my children growing up in a War Zone.
--
Jerry Han-CRC-DOC-Div. of Behavioural Research-"jhan@debra.dgbt.doc.ca"
///////////// These are my opinions, and my opinions only. \\\\\\\\\\\\\
\\\\\\\\\ A proud and frozen member of the Mighty Warriors Band ////////
"Memories of those I've left behind, still ringing in my ears."-Genesis-
From: rja14@cl.cam.ac.uk (Ross Anderson)
Subject: Re: Tempest
Nntp-Posting-Host: ely.cl.cam.ac.uk
Organization: U of Cambridge Computer Lab, UK
Distribution: na
Lines: 19
res@colnet.cmhnet.org (Rob Stampfli) writes:
> Wouldn't a a second monitor of similar type scrolling gibberish and adjacent
> to the one being used provide reasonable resistance to tempest attacks?
We've got a tempest receiver in the lab here, and there's no difficulty in
picking up individual monitors. Their engineering tolerances are slack enough
that they tend to radiate on different frequencies. Even where they overlap, you
can discriminate because they have different line synch frequencies - you can
lock in on one and average the others out.
The signals are weird in any case, with varying polarisations and all sorts
of interactions with the building. Just moving a folded dipole around is also
highly effective as a (randomised) means of switching from one monitor to
another,
Ross
From: smb@research.att.com (Steven Bellovin)
Subject: Re: (new) reason for Clipper alg'm secrecy
Organization: AT&T Bell Laboratories
Lines: 31
In article <1993Apr20.155924.29995@news.clarkson.edu>, tuinstra@signal.ece.clarkson.edu.soe (Dwight Tuinstra) writes:
> First, note that the "experts" will only look at "details", and of just
> the algorithm:
>
>     In addition, respected experts from outside the
>     government will be offered access to the confidential details of
>     the algorithm to assess its capabilities and publicly report
>     their findings.
>
> Why not the chip design?  Well, here's the possiblity:  in addition to
> encryption, the chip pre-processes voice signals to make them easier
> to analyze/transcribe electronically.  The chip, once widespread, might
> effectively be part of a massively parallel computer for "voice-
> grepping" the US phone network (or the criminal & wrong-thinking patrons
> thereof).
First of all, the chip doesn't do that.  It runs at 16 megabits/second,
which is far beyond what you need for voice.  It's obviously intended
for data as well, and on high-speed lines at that.
Second -- what advantage is there to doing the processing in the phone?
I don't care how fancy that chip is; it's not as fancy as the roomful
of analyzers at Fort Meade running the program they'll have 5 years from
now.  They can't update every Clipper chip that's out there.
Third -- if they did do this preprocessing in the chip, it would probably
have a serious effect on recognizability of the voice patterns.  If
nothing else, that would hurt the acceptability of the product.  The
V.32bis modems are just barely fast enough to do a good job on properly-
massaged voice as is; add any more to the mix, and you're completely out
of the ballpark.
From: steve-b@access.digex.com (Steve Brinich)
Subject: S1, S2
Organization: Express Access Online Communications, Greenbelt, MD USA
Lines: 13
NNTP-Posting-Host: access.digex.net
> Second question: Why!?!? Why is such a strange procedure used, and not
>a real RNG ? This turns those S1,S2 in a kind of bottleneck for system-
>security.
The only theory that makes any sense is that S1 and S2 are either the
same for all chips, or vary among very few possibilities, so that anyone
trying to break the encryption by brute force need only plow through the
possible serial numbers (2^30, about one billion), multiplied by the number
of different S1, S2 combinations.
From: rj@ri.cadre.com (Rob deFriesse)
Subject: Can DES code be shipped to Canada?
Article-I.D.: fripp.1993Apr22.125402.27561
Reply-To: rj@ri.cadre.com
Organization: Cadre Technologies Inc.
Lines: 13
Nntp-Posting-Host: 192.9.200.19
Someone in Canada asked me to send him some public domain DES file
encryption code I have.  Is it legal for me to send it?
Thanx.
--
Eschew Obfuscation
Rob deFriesse                    Mail:  rj@ri.cadre.com
Cadre Technologies Inc.          Phone:  (401) 351-5950
222 Richmond St.                 Fax:    (401) 351-7380
Providence, RI  02903
I don't speak for my employer.
From: throopw%sheol@concert.net
Subject: Re: Clipper considered harmful
Lines: 59
: From: shirriff@sprite.berkeley.edu (Ken Shirriff)
: Message-ID: <1r24us$oeh@agate.berkeley.edu>
: It seems likely to me that that a large subset of encrypted communications
: would be archived to tape so they could be read if sometime in the future
: probable cause arises and a warrant is obtained.
I think it is unlikely that data like this could be used in court.
Currently LEAs can install wiretaps on large numbers of phones, record
calls without listening to them, and then post-facto obtain warrants
and listen to calls after probable cause is established.  But this
strategy wouldn't get the stuff admitted in court.  (At least, not
in the near term.)
In other words, near as I can tell, the thing that makes such evidence
inadmissable is the interception without a warrant, not the attempt to
interpret what was intercepted without a warrant.  I'd be surprised
that archiving data without consent would be interpreted as anything
but analogous to a wiretap by the courts.
Note that that doesn't mean I think it won't be done if technically
feasible.  Just as I'm sure many wiretaps are done now without
warrants, just to fish for avenues to investigate.  So in the future,
start surveilance, start archiving data, trump up some probable cause,
decrypt post-facto after the warrant is in hand, and the investigation
gets a boost from data that, sadly, won't ever be presented to a jury.
While I'm posting...  for an interesting cautionary tale projecting this
archiving scenario to extremes, read "Lacey and his Friends", a
collection of sf stories by David Drake.  The US starts down the
slippery slope by archiving *everyghing*.  But don't worry folks, it's
stored in a secure repository where nobody but LEAs with warrants can
get to it.  And by the way, we'll be installing cameras on all major
streets.  Hey, this is nothing new, we already have cameras in banks and
teller machines, don't we?
And then we'll pass laws requiring cameras covering *all* public
places.  Then in some private places.  Then we'll make it a crime ever
to be out of range of a camera, except in legally licensed privacy
cubicles.  Only alone.  And with a thorough body search before and
after.  But, see, there's still a right to privacy.  We haven't
curtailed any rights, not really.  And just think how much easier it'd
be to solve crimes in such a situation: just obtain a warrant, put on a
VR helmet and take a walk down memory lane.
And hey, nobody'll be tracking *you* or *me*, no need to be self-conscious.
After all, if you're not doing anything illegal...
Funny, though.  While speeding and the radar detector industry became
pretty much a thing of the past, somehow all this didn't elminate all
crime in the story.  And somehow, politicians got exemptions on grounds
of national security, and rich corporations got exemptions for their
execs on grounds of industrial espionage and the preservation of
competition.  And not everybody was exactly happy with the system.
I can't imagine why.
--
Wayne Throop   throopw%sheol@concert.net
throop%aurgate@concert.net
From: grady@netcom.com (1016/2EF221)
Subject: IDEA vectors?
Organization: capriccioso
X-Newsreader: TIN [version 1.1 PL6]
Lines: 11
I am testing IDEA block cipher implementations for correctness
and needs some golden test vectors.  I've looked through
the postscript IDEA chapter but the single example gives me
zero degrees of freedom.  I'll contact the inventor if necessary
but since we are NOT paying him money for use of his invention,
I'd like to offload this from him.  Anybody got vectors?
(No disease vectors, please).
--
grady@netcom.com  2EF221 / 15 E2 AD D3 D1 C6 F3 FC  58 AC F7 3D 4F 01 1E 2F
From: clipper@csrc.ncsl.nist.gov (Clipper Chip Announcement)
Subject: Re: The [secret] source of that announcement
Organization: National Institute of Standards & Technology
Lines: 65
In article <C5uxGv.Dv7@panix.com> habs@panix.com (Harry Shapiro) writes:
>In <1r1om5$c5m@slab.mtholyoke.edu> jbotz@mtholyoke.edu (Jurgen Botz)
>writes:
>
>>Even more interesting: the SMTP server at csrc.ncsl.nist.gov no longer
>>recognizes the 'expn' and 'vrfy' commands...
>
>>   telnet csrc.ncsl.nist.gov smtp
>>   Trying 129.6.54.11...
>>   Connected to csrc.ncsl.nist.gov.
>>   Escape character is '^]'.
>>   220 first.org sendmail 4.1/NIST ready at Tue, 20 Apr 93 17:01:34 EDT
>>   expn clipper
>>   500 Command unrecognized
>
>>Seems like sombody didn't like your snooping around, Marc.
>
>Then it is a good thing we already have this:
>
>The csspub mailing list: csspab@mail-gw.ncsl.nist.gov, and address on
> [rest of names deleted]
Sigh... my version of 'rn' asked me whether I really want to send this
posting!
You may as well know that all this stuff about the secret source of the
Clipper announcement is because of a silly mistake.  I am the administrator
of csrc.ncsl.nist.gov, alias first.org.  It's a system set up to help out
the needs of FIRST, a Forum of Incident Response and Security Teams, which
includes a number of world-wide incident response teams such as CERT/CC and
other places in Europe.  As to the VRFY and EXPN commands, they are normally
disabled, since early on we didn't want crackers to find out the names of
incident response folks on our mailing lists.  We had a disk crash several
months ago which required completely rebuilding the O/S files - same old
story, our backups weren't especially helpful.  As you can guess, I didn't
remember to re-disable VRFY and EXPN until I saw people on the net trying to
find out who was behind clipper@csrc...  When I saw people's names posted
here, I felt it was time to clear things up.  So, EXPN and VRFY on csrc have
always been disabled in the past for reasons having nothing to do with
Clipper.
I posted the White House announcements at the request of policy folks here
because csrc also provides Usenet service.  I posted them from an account
called 'clipper.'  I also created an alias called 'clipper' that contains
the addresses of members of the NIST Computer Security Privacy and Advisory
Board, set up under law of the Computer Security Act of 1987, and addresses
of other individuals not affiliated with NIST but involved in cryptography,
security, and privacy - I believe that these individuals were included on
this list because NIST felt it important to get them the Clipper information
first-hand.
The 'clipper' alias is there for the benefit of those named above.  It is
not a source for information, it was set up solely to monitor any initial
traffic.  Individuals on the list have requested that they continue to get
traffic that is not already duplicated on Usenet.
While you can rightfully say we were a bit disorganized in handling this,
I would ask that people stop speculating about any hidden agendas or motives
of the individuals on the 'clipper' alias - I've already apologized to them
for what's happened.  Disabling EXPN and VRFY is an increasingly common
practice (albeit unfriendly to some), and any effect of disabling it again
was unintentional.
-John Wack
From: karl@genesis.MCS.COM (Karl Denninger)
Subject: Re: Do we need the clipper for cheap security?
Organization: MCSNet, Chicago, IL
Lines: 39
NNTP-Posting-Host: localhost.mcs.com
In article <9304201003.AA05465@pizzabox.demon.co.uk> gtoal@gtoal.com (Graham Toal) writes:
>	gtoal@gtoal.com (Graham Toal) writes:
>	>
>	>In the UK, it's impossible to get approval to attach any crypto device
>	>to the phone network.  (Anything that plugs in to our BT phone sockets
>	>must be approved - for some reason crypto devices just never are...)
>	>
>
>	Whats the difference between a V.32bis modem and a V.32bis modem?
>
>	I'm not being entirely silly here: what I'm pointing out is that the
>	modems that they have already approved for data transmission will work
>	just fine to transmit scrambled vocoded voice.
>
>Absolutely.  I just meant that no secure *dedicated* crypto device has
>ever been given approval.  Guerrilla underground devices should be well
>possible with today's high-speed modems (not that I can think of many v32bis
>modems that are approved either mind you - just the overpriced Couriers)
>
>Can someone tell me if hardware compression is or is not needed to run
>digital speech down 14.4K?  I think it is; I've heard it's not.  Lets
>say 8 bit samples.  Would *raw* data at the corresponding sampling rate
>be usable?  If not, how fancy does the compression need to be?
Reasonably fancy.
Standard "voice" circuits run at 56kbps inter-exchange in the US.
Therefore, you need to achieve 4:1 to get standard voice quality.
If you're willing to give up some quality, you need only 2:1.  This is still
acceptable from a speech standpoint; it will be a little less faithful to
the original, but certainly intelligable.  That's all you really need for
this application.
--
Karl Denninger (karl@genesis.MCS.COM) 	| You can never please everyone except
Data Line: [+1 312 248-0900]		| by bankrupting yourself.
LIVE Internet in Chicago; an MCSNET first!
From: croley@magic.mcc.com (David Croley)
Subject: Re: new encryption
Organization: MCC Experimental Systems Lab
Lines: 48
In article <1993Apr21.225435.6292@wam.umd.edu>, psionic@wam.umd.edu (Haywood J. Blowme) writes:
|>    As promised, I spoke today with the company mentioned in a Washington
|> Times article about the Clipper chip announcement. The name of the company
|> is Secure Communications Technology (Information will be given at the end
|> of this message on how to contact them).
|>
|>     ...
|>
|>    His belief is that AT&T was made known of the clipper well before the
|> rest of the industry. This is for several reasons, several of which are:
|>
This is a very good point.  AT&T obviously knew and participated in the
development of the Clipper chip.  This amounts to unfair business practice and
gives AT&T an early monopoly on the market [hopefully a non-existant market].
Other companies that compete with AT&T in the cellular market (Motorola, NEC, etc)
have grounds to file a complaint over this.
|>
|> Right now the company is afraid that the new clipper chip will put them out
|> of business. This is a very real possibility. So they really need help in
|> stopping the clipper chip from becoming a standard. If you want to contact
|> them, they can be reached at..
|>
|> Secure Communications Technology
|> 8700 Georgia Ave. Suite 302
|> Silver Spring, MD
|>
|> (301) 588-2200
|>
|>  ...
It would seem that the one fact that the government has overlooked in this
whole fiasco is the economic standpoint.  As others have mentioned, the most
difficulty the Clipper chip faces is an economic one.  Let's face it, the
average consumer doesn't care or know that the Clipper is a bad idea.  If
there is a perceived need for cellular encryption, then the companies will
provide one.  Most likely, a standard will emerge.  But if the Clipper is
too expensive (and $25 a chip is way too much) then they will develope their
own or buy a cheaper one.  I give SCT my full support, and hope the
Clipper chip goes the way of the Beta video tape format.
Also hope they get sued over re-using the name Clipper.
--
---------------------------------------Cyberspace:--------------------------
| David T. Croley | MCC - Exp Sys Lab | A place not real, no stone, no steel.|
| croley@mcc.com  | UT Austin, Texas  | A ghost unseen...the world "between".|
----------------------------------------------------------------------------
From: gregb@den.mmc.com (gregb)
Subject: Looking for crypto paper
Distribution: usa
Organization: Martin Marietta Astronautics, Denver
Lines: 17
Nntp-Posting-Host: tosgcla.den.mmc.com
Looking for PostScript or Tex version of a paper called:
"PUBLIC-KEY CRYPTOGRAPHY"
Written by:
James Nechvatal
Security Technology Group
National Computer Systems Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899
December 1990
The version I obtained is plain text and all symbolic character
formatting has been lost.
--
gregb@tosgcla.den.mmc.com
From: steve-b@access.digex.com (Steve Brinich)
Subject: Re: Overreacting (was Re: Once tapped, your code is no good any more)
Organization: Express Access Online Communications, Greenbelt, MD USA
Lines: 13
Distribution: na
NNTP-Posting-Host: access.digex.net
> Somebody asked me what was wrong about overreacting in cases such as this.
>
> The reason is very simple:  How many people do you want to die in a riot?
>In a new Civil War?
Not me -- which is precisely why the government must be cut off at the
knees when it pulls stunts like this, lest the situation worsen to the point
where extreme measures are required.
From: msnyder@nmt.edu (Rebecca Snyder)
Subject: public awareness (wasRe: text of White House announcement and Q&As on clipper chip encryption)
Organization: New Mexico Tech
Distribution: na
Lines: 50
In article <2076@rwing.UUCP> pat@rwing.UUCP (Pat Myrto) writes:
>I think this is no accident.  It comes from the same philosophy that
>the government rules/controls the people, not the people controlling
>the government, that the unconnected citizens are not sophisticated enough
>to know what is best for them, so the government must tell the people
>what they need or do not need ... "we know best...".  And the idea that
>that a commoner can defend himself against government eavesdropping
>or unlawful attack is totally unacceptable to people with this outlook.
>
>
>Combine this all with pushing for national identity cards with 'smart
>chips' to encode anything they please (internal passport) under the
>guise of streamlining the State People's Health Care System, and with
>(you can be certain) more jewels yet to come, and one sees an extremely
>ominous trend.  So what if "1984" will be ten years late... it still is
>turning out to be an amazingly accurate prophecy... unless a LOT of
>people wake up, and in a hurry.
>
>One should ALWAYS have every red warning light and bell and danger flag
>come up when the government seeks to set itself apart in regard to
>rights, etc.  from the unconnected/unprivileged citizen (or should we
>now be saying 'subject' instead?)...  Why SHOULDN'T the average person
>have a good, secure system of data security, not dependent on nebulous
>'safeguards' for maintaining that security?  Why SHOULDN'T the average
>person be able to defend himself from an agency gone rogue?  0I am sure
>the Feds could break into any data they really wanted to (but it would
>take some WORK), and using the same logic, one should not be allowed to
>have a good safe, unless a duplicate of the key(s) or combination are
>submitted for 'safekeeping' by the government?  I don't really see a
>difference, philosophically.  Encrypted data sure won't evaporate, not
>with such high-tech tools as a TAPE RECORDER...
>
The average amerikan today seems to think that the government should be
able to eavesdrop on everyone (else).  Opinion polls show that most
people belive the Bill of Rights to grant too much freedom to people,
when it is not identified as such (BTW, if anyone knows of a cite for that,
I'd love to have it).  Not only does this mean that these people are
willing to give up everyone (else's) rights, they don't even know what
the Bill of Rights actually says.
How can we show the average person (not the average USENET reader) that
people are actually entitiled to these rights?  So many people don't
care if the government is taking more and more control of us all, a little
at a time.
If there was some sort of awareness of what the government is trying
to do by a majority of the US population... Just think about what
could be accomplished - but there are so many that trust, unthinkingly,
in whatever the media and government tell them.
From: "Jon C. R. Bennett" <jb7m+@andrew.cmu.edu>
Subject: Ideas on Clipper
Organization: Robotics Institute, Carnegie Mellon, Pittsburgh, PA
Lines: 92
NNTP-Posting-Host: andrew.cmu.edu
I have an idea as to why the encryption algorithm needs to be keep secret,
and some things that i think it implies. (Of course these could all be
wrong.....)
from
THE CLIPPER CHIP: A TECHNICAL SUMMARY
Dorothy Denning
Revised, April 21, 1993
.
.
.
The Clipper Chip contains a classified single-key 64-bit block
encryption algorithm called "Skipjack."  The algorithm uses 80 bit keys
(compared with 56 for the DES) and has 32 rounds of scrambling
(compared with 16 for the DES).  It supports all 4 DES modes of
operation.  The algorithm takes 32 clock ticks, and in Electronic
Codebook (ECB) mode runs at 12 Mbits per second.
Each chip includes the following components:
the Skipjack encryption algorithm
F, an 80-bit family key that is common to all chips
N, a 30-bit serial number (this length is subject to change)
U, an 80-bit secret key that unlocks all messages encrypted with the chip
.
.
.
ENCRYPTING WITH THE CHIP
To see how the chip is used, imagine that it is embedded in the AT&T
telephone security device (as it will be).  Suppose I call someone and
we both have such a device.  After pushing a button to start a secure
conversation, my security device will negotiate an 80-bit session key K
with the device at the other end.  This key negotiation takes place
without the Clipper Chip.  In general, any method of key exchange can
be used such as the Diffie-Hellman public-key distribution method.
Once the session key K is established, the Clipper Chip is used to
encrypt the conversation or message stream M (digitized voice).  The
telephone security device feeds K and M into the chip to produce two
values:
E[M; K], the encrypted message stream, and
E[E[K; U] + N; F], a law enforcement field ,
which are transmitted over the telephone line.  The law enforcement
field thus contains the session key K encrypted under the unit key U
concatenated with the serial number N, all encrypted under the family
key F.  The law enforcement field is decrypted by law enforcement after
an authorized wiretap has been installed.
------------------
suppose i knew how the algorithm worked and knew the N for my chip, but
did not know F, then by cryptanalysis i might be able to determine F from
if law enforcement field
E[E[K; U] + N; F]
not knowing N would might make this much harder.
Now suppose that I know F, (either legitimately or not),
If I know K (either because I am involved in the conversation, or I know U
for a party in the conversation), I may now be able to determine U for the
other party.
If I know F I can also defeat the law enforcement field, since I could
make my own, with a different K then the one I am using. Knowing F also
allows traffic analysis to be performed. So I might not know what you are
saying but I could know who you are saying it too.
Now I admit that someone trying to compute U will not have lots of
messages to work from, but since we have no way of knowing that the key
generation method does not (deliberately?) generate weak keys, or for that
matter that the published method is in fact used, perhaps the U's will be
chosen from know weak keys for the system.
Obviously the compromise of F would be a disaster, both to law enforcement
for whom this whole thing is designed, and for the people who believe that
it is giving them security. F is but one number, and I sure that alot of
people (more then 1) know what it is (and if some "panel of experts" is
going to check it over for flaws then many more will know F, forget
grinding chips, bribery and blackmail work just fine.
So, am I wrong? Or are these problems.
jon
From: pat@rwing.UUCP (Pat Myrto)
Subject: Re: Once tapped, your code is no good any more.
Article-I.D.: rwing.2091
Distribution: na
Organization: Totally Unorganized
Lines: 17
In article <1r21t1$4mc@access.digex.net> steve-b@access.digex.com (Steve Brinich) writes:
<
< > I wonder if she landed such a fat fee from cooperation with the NSA in
< >the design and propoganda stages that she doesn't care any more?
<
<  Which is to say: is the NSA -totally- perfidious, or does it at least
<have the redeeming virtue of taking care of its own? <g>
Of course they take care of their own ... very well ... until the person
has 'outlived his/her/undefined usefulness'... then 'elimination' becomes
a consideration...  :-)
--
pat@rwing.uucp      [Without prejudice UCC 1-207]     (Pat Myrto) Seattle, WA
If all else fails, try:       ...!uunet!pilchuck!rwing!pat
WISDOM: "Only two things are infinite; the universe and human stupidity,
and I am not sure about the former."              - Albert Einstien
From: ted@nmsu.edu (Ted Dunning)
Subject: Re: Off the shelf cheap DES keyseach machine (Was: Re: Corporate acceptance of the wiretap chip)
Organization: Computing Research Lab
Lines: 36
<1993Apr21.001230.26384@lokkur.dexter.mi.us>
<C5uvn4.MF7@austin.ibm.com> <strnlghtC5wCMo.Fx5@netcom.com>
NNTP-Posting-Host: lole.nmsu.edu
In-reply-to: strnlght@netcom.com's message of Thu, 22 Apr 1993 17:59:12 GMT
In article <strnlghtC5wCMo.Fx5@netcom.com> strnlght@netcom.com (David
Sternlight) writes:
>At the company I worked for previously, I received a file that was
>des encryped and the person that had sent it, went on vaction.
>Rather than wait two weeks I set up a straight frontal attack with
>one key at a time.  It only took two(2) days to crack the file.
>No, I don't have any faith in DES.
Taking this at face value (though it seems quite dissonant with
much else that has been published here about brute force DES
cracking, unless Russell was lucky with respect to the key), I'd be
very interested in whether the program Russell used is available?
key search is very practical in many real situations since people use
such stupid keys on the average.  password crackers know this well.
Depending on his answer, this could be an appalling development
calling into question both DES and RSA/DES.
not really.  in fact, public key based communication systems very
often pick keys automatically which are much better than passwords or
pass phrases.
If any bright programmer with a little idle machine time can crack
a single DES message in a couple of days (assuming no tricks that
are message-specific),
if a person picked the password or pass phrase, then the key search is
pretty straightforward.  in running english text, the average content
of a single word is about 8 bits.  in pass phrases, this may increase
to 10 bits or so.  searching 30bit spaces is semi-practical even in
software and searching 40bit spaces isn't outrageous to imagine with
hardware assists of moderate size.
Subject: Re: Organized Lobbying for Cryptography
From: kubo@zariski.harvard.edu (Tal Kubo)
Distribution: inet
Organization: Dept. of Math, Harvard Univ.
Nntp-Posting-Host: zariski.harvard.edu
Lines: 27
In article <C5uprt.GMq@dcs.ed.ac.uk> pdc@dcs.ed.ac.uk (Paul Crowley) writes:
>
>>Perhaps these encryption-only types would defend the digitized porn if it
>>was posted encrypted?
>
>>These issues are not as seperable as you maintain.
>
>In fact, since effective encryption makes censorship impossible, they
>are almost the same issue and they certainly fall into the brief of the
>EFF.
It also falls within the purview of the ACLU, but that doesn't mean
the ACLU (or the EFF) would be the most effective instrument to
"win the hearts and minds" in favor of access to cryptography.
It's precisely slogans like "cryptography makes censorship impossible"
which stand to torpedo any attempt to generate a broad consensus in favor
of encryption.  It is not true, and in the context of a public debate it
would be a dangerous red herring.  Advocates of strong crypto had better
prepare themselves to answer such charges in pragmatic terms that laypeople
and politicians can sympathize with. The usual mumblings about
Constitutional amendments are not enough.
Tal  kubo@math.harvard.edu
From: davidc@montagar.com (David L. Cathey)
Subject: Re: The [secret] source of that announcement
Organization: Montagar Software Concepts, Plano TX
Lines: 19
In article <gradyC5uAMw.BnG@netcom.com>, grady@netcom.com (1016/2EF221) writes:
> Maybe we should start a newsgroup for the distribution of encrypted
> posts intended of members of affinity groups with a shared private
> key.  For example at the coming up Cypherpunks meeting, a private
> key corresponding to that particular meeting could be passed out
> by a moderator.  Minutes, followup comments to other participants,
> and so on could be posted to the alt.encrypted group for the use
> of the people who attended. Communiques intended by the group for
> non-attendees could of course just be signed using the private key
> but otherwises not encrypted.
I like it.  PGP would be useful, I guess.  Although I don't have
a working version for VMS yet... :-(
> grady@netcom.com  2EF221 / 15 E2 AD D3 D1 C6 F3 FC  58 AC F7 3D 4F 01 1E 2F
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
David L. Cathey		                |INET: davidc@montagar.com
Montagar Software Concepts              |UUCP: ...!montagar!davidc
P. O. Box 260772, Plano TX  75026-0772  |Fone: (214)-618-2117
From: redsonja@olias.linet.org (Red Sonja)
Subject: Re: Once tapped, your code is no good any more.
Distribution: na
Organization: Utter Chaos in Islip, Long Island, New York (we think)
Lines: 26
In article <1993Apr20.054308.15985@Celestial.COM> bill@Celestial.COM (Bill Campbell) writes:
>In <strnlghtC5p7zp.3zM@netcom.com> strnlght@netcom.com (David Sternlight) writes:
>
>:In article <Apr18.194927.17048@yuma.ACNS.ColoState.EDU>
>:holland@CS.ColoState.EDU (douglas craig holland) writes:
>
>:>Note that measures to protect yourself from
>:>TEMPEST surveillance are still classified, as far as I know.
>
>:I think this to be inaccurate. One can buy TEMPEST equipment commercially.
>:Even Macs.
>
>Sure you can buy a TEMPEST approved Mac -- if you have enough
>money.  I haven't had any reason to look at this type of pricing
>for about 10 years, but a TEMPEST rating in 1982 would raise the
>price of a $2,495.00 Radio Shack Model III to something around
>$15,000.00.
>
Or just dig a deep enough hole in the ground. 50 feet should do it.
--
redsonja@olias.linet.org     \\\RS///     Self possession is 9/10 of the law.
Alien: "We control the laws of nature!" | "How come when it's human, it's an
Joel: "And you still dress that way?"   | abortion, but when it's a chicken,
(MST3K#17 - Gamera vs Guiron)           | it's an omelet?" - George Carlin
From: gtoal@gtoal.com (Graham Toal)
Subject: Let's build software cryptophones for over the internet...
Lines: 92
Well, after a lot of trawling through archives, I found the post
I reproduce in full below.  Is it time to get together to develop
a tcp/ip standard for crypto voice that we could then layer on
point-to-point SLIP as *the* free standard for crypto voice like
pgp is for mail?
(PS Note the date of this post.  Appropriate, huh? :-) )
---
From jpcampb@afterlife.ncsc.mil Thu Jul  9 11:50:11 1992
From: jpcampb@afterlife.ncsc.mil (Joe Campbell)
Newsgroups: comp.compression.research
Subject: Re: sound compression algorithms
Date: 4 Jul 92 14:46:04 GMT
Organization: The Great Beyond
In article <1992Jun26.165210.15088@sequent.com> lff@sequent.com (Lou Fernandez) writes:
>The techniques for production systems revolve around Code Excited Linear
>Prediction (CELP) algorithms which capture 20 ms or so of speech and
>attempt to match the speech with a combination of signals from a
>codebook, choosing the combination which minimizes the error....
In case you'd like to experiment with CELP, you can obtain a software
implementation of the 4800 bps Fed Std CELP coder for free:
The U.S. DoD's Federal-Standard-1016 based 4800 bps code excited linear
prediction voice coder version 3.2 (CELP 3.2) Fortran and C simulation source
codes are now available for worldwide distribution at no charge (on DOS
diskettes, but configured to compile on Sun SPARC stations) from:
Bob Fenichel
National Communications System
Washington, D.C.  20305
1-703-692-2124
1-703-746-4960 (fax)
In addition to the source codes, example input and processed speech files
are included along with a technical information bulletin to assist in
implementation of FS-1016 CELP.  (An anonymous ftp site is being considered
for future releases.)
Copies of the actual standard "Federal Standard 1016, Telecommunications:
Analog to Digital Conversion of Radio Voice by 4,800 bit/second Code
Excited Linear Prediction (CELP)" are available for $2.50 each from:
GSA Rm 6654
7th & D St SW
Washington, D.C.  20407
1-202-708-9205
The following articles describe the Federal-Standard-1016 4.8-kbps CELP
coder (it's unnecessary to read more than one):
Campbell, Joseph P. Jr., Thomas E. Tremain and Vanoy C. Welch,
"The Federal Standard 1016 4800 bps CELP Voice Coder," Digital Signal
Processing, Academic Press, 1991, Vol. 1, No. 3, p. 145-155.
Campbell, Joseph P. Jr., Thomas E. Tremain and Vanoy C. Welch,
"The DoD 4.8 kbps Standard (Proposed Federal Standard 1016),"
in Advances in Speech Coding, ed. Atal, Cuperman and Gersho,
Kluwer Academic Publishers, 1991, Chapter 12, p. 121-133.
Campbell, Joseph P. Jr., Thomas E. Tremain and Vanoy C. Welch, "The
Proposed Federal Standard 1016 4800 bps Voice Coder:  CELP," Speech
Technology Magazine, April/May 1990, p. 58-64.
For U.S. FED-STD-1016 (4800 bps CELP) _realtime_ DSP code
and information about products using this code, contact:
John DellaMorte
DSP Software Engineering
165 Middlesex Tpk, Suite 206
Bedford, MA  01730
1-617-275-3733
1-617-275-4323 (fax)
dspse.bedford@channel1.com
DSP Software Engineering's code can run on a DSP Research's Tiger 30 board
(a PC board with a TMS320C3x and analog interface suited to development work)
or on Intellibit's AE2000 TMS320C31 based 3" by 2.5" card.
DSP Research                Intellibit
1095 E. Duane Ave.          P.O. Box 9785
Sunnyvale, CA  94086        McLean, VA  22102-0785
(408)773-1042               (703)442-4781
(408)736-3451 (fax)         (703)442-4784 (fax)
--
.............................................................................
; Joe Campbell  N3JBC  jpcampb@afterlife.ncsc.mil  74040.305@compuserve.com ;
; My opinions are mine!   Happiness = Reality - Expectations, Click & Clack ;
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From: sean@sdg.dra.com
Subject: Re: Fighting the Clipper Initiative
Organization: Data Research Associates, St. Louis MO
Lines: 22
In article <he1pb02@rhyolite.wpd.sgi.com>, vjs@rhyolite.wpd.sgi.com (Vernon Schryver) writes:
> In article <strnlghtC5toC6.KIu@netcom.com>, strnlght@netcom.com (David Sternlight) writes:
>>              Even the Department of Agriculture has successfully kept crop
>> forecasts from leaking prematurely.
>
> Sheesh!  Remember the big scandal a year or two (or 3?) ago about
> exactly such leaks?
My choice for the escow house would be the Smithsonian, and someplace on
the west coast.  My biggest concern isn't that the escrow house could
be compromised (it will be), but the fact it has been compromised will
be kept secret.
The keys could be kept under glass, with 24-hour C-SPAN coverage.  If you
thought your key had been stolen just turn on the cable, and wait until
the roving camera reachs the musuem case with your key.  Or if you think the
C-SPAN satellite has been compromised, take a tour of the Smithsonian
yourself, and view the seal on your key.
--
Sean Donelan, Data Research Associates, Inc, St. Louis, MO
Domain: sean@sdg.dra.com, Voice: (Work) +1 314-432-1100
From: gtoal@gtoal.com (Graham Toal)
Subject: Re: Let's build software cryptophones for over the internet...
Lines: 27
I forwarded an old posting about CELP speech compression:
In case you'd like to experiment with CELP, you can obtain a software
implementation of the 4800 bps Fed Std CELP coder for free:
The U.S. DoD's Federal-Standard-1016 based 4800 bps code excited linear
prediction voice coder version 3.2 (CELP 3.2) Fortran and C simulation source
codes are now available for worldwide distribution at no charge (on DOS
diskettes, but configured to compile on Sun SPARC stations) from:
I've since been told that the source of this is on cygnus.com
in /pub/celp.speech.tar.Z
I'm not in a position to; any Sun tcp/ip gurus out there who think they
can marry this with netfone by the end of the week? ;-)  Seriously.  I
think someone with real net access and two sparcs could have this running
by the end of the week.  Then we ask the pgp guys to add a bytestream
crypto filter.  Two weeks at the most.  [Damn, I wish I had my sparc
back... I'm stuck on a 25mhz 386sx]
Share and Enjoy!
G
PS  You'll have to use archie to find netfone - I have a copy but no note
of where it's from; author in the docs is kelvin@autodesk.com and he
appears to be located in France
From: gtoal@gtoal.com (Graham Toal)
Subject: Re: Do we need the clipper for cheap security?
Lines: 43
: From: caronni@nessie.cs.id.ethz.ch (Germano Caronni)
: In article <9304201003.AA05465@pizzabox.demon.co.uk> gtoal@gtoal.com (Graham Toal) writes:
: >Can someone tell me if hardware compression is or is not needed to run
: >digital speech down 14.4K?  I think it is; I've heard it's not.  Lets
: >say 8 bit samples.  Would *raw* data at the corresponding sampling rate
: >be usable?  If not, how fancy does the compression need to be?
: As far as I know ISDN (call it Swissnet here, and it's being plugged in) it's
: 8 bit 8000Hz (gives you one channel of 64kBit/sec) I guess you should not go
: below a sampling rate of 6000 Hz if you want to have same quality as on an
: analog-line. Anybody knows compression-algorithms & -factors for voice ?
I've posted some info on CELP coding on sci.crypt.  Looks like you can
squeeze speech into 4000bps if you have a fast enough computer like a
sparcstation (or a Newton with the Acorn Risc Machine in it :-) )
This drops the bandwidth to so low a figure that it's feasible to run
speech over tcp/ip running on top of slip down a v32bis modem.  Not only
will this let us run point to point encrypted speech, it'll let us
run speech internationally over the internet if no-one stops us by
getting *very* heavy about regulations.  The thought of this, if the
administration realised, would probably scare them shitless.
Now of course the trick is to develop and define a standard protocol
for internet speech *damn fast*, allowing anyone who feels brave to
inplement custom handheld hardware as well as us hacking it on our
workstations.  Shouldn't be too difficult.  The CELP stuff is standardised,
we use tcp/ip streams, and a protocol allowing silences to be used to
catch up on any net lag, and also to avoid sending any data during
silences (ie it's not wise to be synchronised real-time on each end
because any net delays would add up to big voice-lags)
As for me, I'm going to press ahead on trying this stuff as soon as
I get my sparc back from being loaned out and buy the necessary microphone.
It'll save me a fortune in calling my friend in texas every night :)
(whether encrypted or not)
You know, surely *someone* is working on this.  Who?  It's so obvious,
why doesn't it exist already?  I've only seen netphone for Suns and
it didn't do the CELP compression so was restricted to ether connections.
G
From: gtoal@gtoal.com (Graham Toal)
Subject: Re: Would "clipper" make a good cover for other encryption method?
Lines: 22
: From: brad@optilink.COM (Brad Yearwood)
: Assume in this case the usual canard-adversary of narcotraficantes.  They
: probably have more cash than the KGB did, and they're probably more generous
: at handing it out.  It will be easier than ever to find or cultivate Walkers
: and Pollards for the keys, and it will be easy enough to find someone to
: reverse-engineer the chip (unless the tamper proofing is damned clever and
: effective).
If the administration *really* believes big-time drug dealers are the threat
(personally I thought it was the CIA and the air force that did all the real
drug shipping :-) ) then they *ought* to take this seriously: unlike the
KGB, drug dealers can make a most convincing argument for cooperation: "help
us and we'll be nice and give you some money, don't help us and we'll start
cutting off your favourite body parts"
After all, it was probably an argument like that that persuaded Jack Ruby to
shoot Oswald in full view of the police.  Life in jail probably seems much
more preferable to most people than several weeks of something nasty
followed by no life at all...
G
From: gtoal@gtoal.com (Graham Toal)
Subject: Re: Off the shelf cheap DES keyseach machine (Was: Re: Corporate acceptance of the wiretap chip)
Lines: 16
: At the company I worked for previously, I received a file that was des encryped
: and the person that had sent it, went on vaction.  Rather than wait two weeks
: I set up a straight frontal attack with one key at a time.  It only took two(2)
: days to crack the file.  No, I don't have any faith in DES.
: A.G.
Fun!  Three questions:
1) What hardware did you use?
2) When you found the key, was there anything about it that was special
that meant you had been lucky to find it early? (Like the first 30 bits
all being 0)
3) ... or did you mean a dictionary attack rather than a binary key attack?
G
From: gtoal@gtoal.com (Graham Toal)
Subject: Re: PGP ideas for IBM systems
Lines: 7
:    I've been thinking about how difficult it would be to make PGP available
: in some form on EBCDIC machines.
Don't encourage them.  Let EBCDIC machines die an honorable death :)
G
From: gtoal@gtoal.com (Graham Toal)
Subject: Re: Is key escrow enough?
Lines: 24
The points raised about checking what is actually -in- the chip, as
opposed to what is allegedly programmed therein, raise yet another trust
issue.  Even if we assume that these "trusted agents" are really entering
a wide range of S1 and S2 seeds (rather than using the same one all the
time to reduce the key search space to 30 bits), I assume they are not
doing so by picking up an iron filing and poking it into the circuitry
at carefully selected points to encode data.  They would presumably be
punching numbers into a computer, which for all they know could program
the chips in a manner completely independent of the S1 and S2 values they
are feeding into the system.
S1 and S2 are clearly the backdoor - we should assume they are all
compromised.  If they're not compromisable, why the hell not use a
hardware true random number source.  There isn't a random number
source *anywhere* in this proposal.  The whole thing is deterministic
from the day the serial number is stamped on the chip.
Nope, it can't be trusted.  This is all about two levels of access -
the (possibly honest) key escrow that police forces have to use, and
ostensibly the FBI; and the back door that lets the NSA decode *everything*
on the fly - and maybe some back-handers to the FBI when they want a
warrantless tab in exchange for favours.
G
From: gtoal@gtoal.com (Graham Toal)
Subject: Re: Do we need the clipper for cheap security?
Lines: 25
: There are chips which perform the voice compression/expansion.  They can't
: be expensive, because they exist in many phones connected to PBXs or on the
: PBX line cards, as well as in a lot of equipment which compresses
: voice-grade circuits to save the cost of long-distance, leased T1s or
: satellite circuits.
: I can't remember the generic term for these chips.  My impression is that
: this was a big deal 10 years ago, but circuits have gotten so cheap that
: it isn't done much now.
Codecs.  They have to get about 6:1 compression on 8 bit samples to squeeze
them down v32bis.  I played around with the lossless 'shorten' program
last night, but it only managed 2.5:1.  I've got some specimen CELP code
but it's not obvious that it runs in real time; I think it's just proof-of-
concept code, and I have some mucking about with file formats to do before
I can put my own sample through it.
Looks like the current option is to use a voice-mail modem with built-in
DSP chip to do this in hardware.  That means two modems for a system,
putting the cost at $600 upwards.  Ouch.  Maybe soon we'll be able to
do it in software on high-powered games consoles - isn't the 3DO an
Acorn RISC machine inside?  That cpu runs like shit off a shovel... and
will be nicely mass-market too.
G
From: gtoal@gtoal.com (Graham Toal)
Subject: Re: Clipper considered harmful
Lines: 12
From: pmetzger@snark.shearson.com (Perry E. Metzger)
You obviously haven't read the information about the system. The chips
put out serial number infomation into the cypher stream to allow
themselves to be identified. The system does not rely on registering
people as owning particular phone units.
And probably as a back door to allow re-generation of the secret key.
Have we determined yet that S1 and S2 don't ever change?
G
From: gtoal@gtoal.com (Graham Toal)
Subject: Re: Clipper considered harmful
Lines: 10
:    Does Dorothy Denning read this group?  If not, is someone on the group
: forwarding questions like these to her, or Martin Hellman, or anyone else
: who's seen more details about the chip?
Of course she does; it's just she's been toasted so often for being
an NSA patsy that she's keeping her head down.  You can always mail
her directly as denning@guvax.acc.georgetown.edu,
denning@cs.cosc.georgetown.edu or denning@cs.georgetown.edu
G
From: et@teal.csn.org (Eric H. Taylor)
Subject: Re: HELP_WITH_TRACKING_DEVICE
Summary: underground and underwater wireless methods
Keywords: Rogers, Tesla, Hertz, underground, underwater, wireless, radio
Nntp-Posting-Host: teal.csn.org
Organization: 4-L Laboratories
Expires: Fri, 30 Apr 1993 06:00:00 GMT
Lines: 36
In article <00969FBA.E640FF10@AESOP.RUTGERS.EDU> mcdonald@AESOP.RUTGERS.EDU writes:
>[...]
>There are a variety of water-proof housings I could use but the real meat
>of the problem is the electronics...hence this posting.  What kind of
>transmission would be reliable underwater, in murky or even night-time
>conditions?  I'm not sure if sound is feasible given the distortion under-
>water...obviously direction would have to be accurate but range could be
>relatively short (I imagine 2 or 3  hundred yards would be more than enough)
>
>Jim McDonald
Refer to patents by JAMES HARRIS ROGERS:
958,829; 1,220,005; 1,322,622; 1,349,103; 1,315,862; 1,349,104;
1,303,729; 1,303,730; 1,316,188
He details methods of underground and underwater wireless communications.
For a review, refer to _Electrical_Experimenter_, March 1919 and June 1919.
Rogers' methods were used extensively during the World War, and was
unclassified after the war. Supposedly, the government rethought this
soon after, and Rogers was convieniently forgotten.
The bottom line is that all antennas that are grounded send HALF of
their signal THRU the ground. The half that travels thru space is
quickly dissapated (by the square of the distance), but that which
travels thru the ground does not disapate at all. Furthermore,
the published data showed that when noise drowned out regular
reception, the underground antennas would recieve virtually noise-free.
IF you find this hard to believe, then refer to the work of the
man who INVENTED wireless: Tesla. Tesla confirmed that Rogers' methods
were correct, while Hertzian wave theory was completely "abberant".
----
ET   "Tesla was 100 years ahead of his time. Perhaps now his time comes."
----
From: w1gsl@athena.mit.edu (Steven L. Finberg)
Subject: New England Ham - Electronic Fleamarket Dates  ** 1 April update  **
Keywords: Fleamarkets Swaps Ham Radio Computers Electronics
Article-I.D.: senator-.1peffgINNarc
Expires: 6 May 1993
Distribution: na
Organization: Massachusetts Institute of Technology
Lines: 112
NNTP-Posting-Host: e40-008-5.mit.edu
New England Area Major Flea Market    ***  DATES  ***      1993        P 1 of 2
All events are Ham Radio/ Electronic related except ~_____~
*******************************************************************************
1993                                                    Contact          Source
*******************************************************************************
3 April Upper Saddle River NJ CRRC   9-3 sell @8     Jack W2EHD 201 768 8360 D
4 April Southington CT SARA @HS $20@6:3 $10@8:3 $3@9      N1GCV 203 621 6191 F
17 April Nashua NH NE Antique RC $5@8 $1@9 @ Res Ctr Church Ray 508 865 1290
18 April Cambridge MA       FLEA at MIT                    Nick 617 253 3776 F
buy $2@9A  sellers $10/sp@7A $8in adv  $35 for season pass
3rd Sunday Each Month April thru October
18 April Webster MA ECARA @ Pt Breeze Rest $3 tables $10   Gary 203 974 2564 F
18 April Agawam MA HCRA @ Southwick Rec Ctr $3@9A     Bob W1ZGP 203 653 0715 F
23,24,25 April Dayton OH  adm $11  sell $30/50++       evenings 513 767 1107 F
2 May Yonkers NY  @Lincoln HS                       Otto WB2SLQ 914 969 1053 A
7-8 May Rochester NH Hoss Traders @FG ex13 off rt 16 $5 noon fri  WA1IVB sase
15 May N Smithfield RI RIFMRS @VFW Main St 8A        Rick K1KYI 401 725 7507
16 May Cambridge MA       FLEA at MIT                      Nick 617 253 3776 F
16 May Pittsfield MA @Taconic HS Sell $5@7 Buy $2@8 Cliff W1SJV 413 743 3334
21-22-23 May Rochester NY ARRL-NY Conv @ Monroe FG  Harold K2HC 800 724 8515 F
5 June S Burlington VT                             Mitch WB2JSJ 802 879 6589
6 June Newington CT @HS Flea                         Les KA1KRP 203 523 0453
12 June Bangor ME Pine St ARC @Hermon ES 146.34/94 8AM-$2 Roger 207 848 3846
20 June Cambridge MA         FLEA at MIT                   Nick 617 253 3776 F
17 July Nashua NH NE Antique RC $5@8 $1@9 @ Res Ctr Church  Ray 508 865 1290
17 July Union ME @ Fairground $3@7AM State Conv    Skeet KA1LPW 207 622 2915
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
LAST UPDATE 3-29-93 de W1GSL                                           P 1 of 2
*******************************************************************************
Additions/ Corrections  via Internet  w1gsl@athena.mit.edu
US Mail   W1GSL POB 82 MIT Br Cambridge MA 02139
SASE for updated copy as issued.

1993                                                   Contact           Source
*******************************************************************************
18 July Cambridge MA         FLEA at MIT                   Nick 617 253 3776 F
3rd Sunday Each Month April thru October
24 July Manchester NH NHARA @HI 8A$4 NE DC 300Ts (no TG) WB1HBB 603 432 6011 F
8 Aug White Planes NY WECAfest                      Sarah N2EYX 914 962 9666 D
8 Aug Wellseley MA WARS+BARS @Babson College         Barry WN1N 508 877 4947 T
14 Aug St Albans ME  @ Snow Mobile Club             Hitch K1HHC 207 796 2282
15 Aug Cambridge MA          FLEA at MIT                   Nick 617 253 3776 F
29 Aug Fall River MA BCRA                            Tom WA1LBK 508 674 4163 T+
11 Sept Windsor ME @ Fairground $3@7AM             Skeet KA1LPW 207 622 2915
12 Sept Gaithersburg MD FAR @Mg Cty FG $5@6A- $7TG Nancy Drahim 703 691 0078 J
12 Sept S Dartmouth MA SE Mass ARA 8A-                Dan N1HCV 508 933 0678  +
19 Sept Cambridge MA         FLEA at MIT                   Nick 617 253 3776 F
19 Sept Sandy Hook CT Candlewood ARA               Harold KB1US              A
25 Sept Greenbush ME  WCSN/BARC @WCSN xmtr          Ed Cockburn 207 732 4366
26 Sept Framingham MA @ HS $12@8 $5@9 $2@10          Barry WN1N 508 877 4947 F
26 Sept Yonkers NY Metro 70 ARC                     Otto WB2SLQ 914 969 1053 A
15,16 Oct Rochester NH Hoss Traders @FG ex13 off rt 16 $5 noon fri      K1RQG
17 Oct Cambridge MA          FLEA at MIT                   Nick 617 253 3776 F
13 Nov Plymouth MA Mayflower RC @Mem Hall 9-3 sell@8   Jim NM1F 508 747 2224
14 Nov Branford CT SCARA @intrm sch                 Brad WA1TAS 203 265 9983 T
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
LAST UPDATE 3-29-93 de W1GSL                                           P 2 of 2
Source F= Flyer  J= John Roberts list   A= ARRL list   WR NV 73 CQ QST = Mags
T= tentative early info    D= W1DL      + = new info this month
This list has been compiled from many sources.  While we believe the info to
be accurate the author can not be responsible for changes or errors.
Check with the sponsoring organizations for more details.
This list will be posted monthly to Usenet if additions have been made.
Mailed copies are sent when additions are made.
*******************************************************************************
Additions/ Corrections  via Internet  w1gsl@athena.mit.edu
US Mail   W1GSL POB 82 MIT Br Cambridge MA 02139
SASE for updated copy as issued.
From: et@teal.csn.org (Eric H. Taylor)
Subject: Re: Electronic Tesla Coils
Summary: Real World Applications
Keywords: tesla, coil, osc, flyback, transformers, wireless, emi, ac, ignition
Nntp-Posting-Host: teal.csn.org
Organization: 4-L Laboratories
Distribution: World
Expires: Fri, 30 Apr 1993 06:00:00 GMT
Lines: 48
In article <1993Mar25.161909.8110@wuecl.wustl.edu> dp@cec1.wustl.edu (David Prutchi) writes:
>In article <C4CntG.Jv4@spk.hp.com> long@spk.hp.com (Jerry Long) writes:
>>Fred W. Culpepper (fculpepp@norfolk.vak12ed.edu) wrote:
>>[...]
>>A couple of years ago I put together a Tesla circuit which
>>was published in an electronics magazine and could have been
>>the circuit which is referred to here. This one used a
>>flyback transformer from a tv onto which you wound your own
>>primary windings. It also used 2 power transistors in a TO 3
>[...]
>10 years ago I built a 1'000,000 volt Tesla, and the thing was VERY
>spectacular, but besides scaring/amazing friends (depending on their
>knowledge of Science), and generating strong EMI, I never found anything
>useful that could be done with it ...  Is there any real-world application
>for Tesla coils today ?
>
>David Prutchi
First of all, realize that Tesla invented AC power generators, motors,
transformers, conductors, etc. Technically, *ALL* transformers are Tesla
coils.  In general though when someone refers to a Tesla coil, they mean
an "air core resonant transformer". The TV flyback version Tesla
coil (see the _Encyclopedia_of_Electronic_Circuits_ V3, 106-1 for
diagram) has NOT an air core. It is of a class of circuit called
"Oscillating Shuttle Circuit" (OSC). Generally OSC's are highly
efficient, but this version uses transistors and resistors,
which are very lossy devices. Typically Tesla used active
reactances instead of passive resistors, so that he could achieve
efficiencies of 99.5%, and better. The usual application of an air-core
resonant transformer, or of an OSC, is to produce strong EMI
for wireless broadcasts. How well do you think your computer
screen would work if we removed the HF HV Tesla (flyback) coil
from it? If we were to remove from our homes and industries all
Tesla coils, our lights would go dark, our cars would sputter
and die, our radios would go silent, our industries would grind
to a halt, and we would have to go back to using coal for heat,
gas for lamps, horses for transportation, steam for power, and
telegraph for communication. Is that real world enough for you???????
GET THE MESSAGE! WE WOULD NOT HAVE 1/100 THE CONVIENIENCES WE HAVE
TODAY IF NOT FOR TESLA. GIVE CREDIT WHERE CREDIT IS DUE!
If it had been up to Edison, we'd still be in the 19th century.
(flame me at your own peril. I'm very good at putting edison down).
----
ET   "Tesla was 100 years ahead of his time. Perhaps now his time comes".
----
From: jml@norman.vi.ri.cmu.edu
Subject: Re: Radar Jammers And Stealth Cars
Nntp-Posting-Host: westend.vi.ri.cmu.edu
Reply-To: jml@visus.com
Organization: School of Computer Science, Carnegie Mellon
Distribution: usa
Lines: 6
Eric H. Taylor writes
> ... If you are determined
> to go faster, get an airplane. They dont have speed limits.
Just don't make a habit of buzzing your local airport at >200 knots
(250 knots if you're flying a jet).  :-)
From: harpe@netnews.louisville.edu (Mike Harpe)
Subject: WANTED: Protel EasyTrax for the MAC
Organization: University of Louisville
Lines: 12
The title says it all.  Contact me via EMAIL if you would can help me out...
Mike Harpe
University of Louisville
P.S.  I KNOW IT IS DISCONTINUED.  I want someone who would like to sell
an old copy.
--
Michael Harpe, Programmer/Analyst      Information Technology, Ormsby Bldg.
harpe@hermes.louisville.edu            University of Louisville
(502)588-5542                          Louisville, Ky. 40292
"He's not a man, he's a remorseless eating machine!" - The Simpsons
From: josephc@cco.caltech.edu (Joseph Chiu)
Subject: Re: What is Zero dB????
Article-I.D.: gap.1pkveuINNduk
Organization: California Institute of Technology, Pasadena
Lines: 33
NNTP-Posting-Host: sandman.caltech.edu
sehari@iastate.edu (Babak Sehari) writes:
>Similarly, people usually use dB for dBm. Another common mistake is spelling
>``db'' instead of ``dB'' as you did in your article. See the ``B'' is for
>``Bell'' company, the mother of AT&T and should be capitalized.
Thus, a deciBell (deci-, l., tenth of + Bell) is a fractional part of the
original Bell.  For example, SouthWestern Bell is a deciBell.
And the measure of current, Amp, is actually named after both the AMP company
and the Amphenol company.  Both companies revolutionized electronics by
simulatenously realizing that the performance of connectors and sockets
were affected by the amount of current running through the wires.
The Ohmite company was the first to characterize resistances by numbers, thus
our use of the Ohms...
Alexander Graham Bell, actually, is where Bell came from...
Actually, Bel refers
>                          With highest regards,
>                               Babak   Sehari.
>--
--
Joseph Chiu        | josephc@cco.caltech.edu  "OS/2: You gotta get this thing!"
MSC 380 - Caltech  |
Pasadena, CA 91126 |   OS/2: The operating system of tomorrow, today.
+1 818 449 5457    |
From: blakey@ug.cs.dal.ca (Jason Blakey)
Subject: Site for projects
Nntp-Posting-Host: ug.cs.dal.ca
Organization: Math, Stats & CS, Dalhousie University, Halifax, NS, Canada
Lines: 6
Does anyone out there know of any ftp sites which deal with
electronics projects, plans, etc?  Any response appreciated.:)
JB
--
............................................................................
Jason Blakey -> blakey@ug.cs.dal.ca
Subject: ACCESS BUS (was I2C bus)
From: srgxnbs@grace.cri.nz
Organization: Industrial Research Ltd., New Zealand.
NNTP-Posting-Host: grv.grace.cri.nz
Lines: 37
From:	MX%"Andy.Macrae@Corp.Sun.COM"  6-APR-1993 06:48:34.96
To:	SRGXNBS
CC:
Subj:	Re: I^2C bus and long haul serial (also Axlo
Return-Path: <Andy.Macrae@Corp.Sun.COM>
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Date: Mon, 5 Apr 93 11:47:28 PDT
From: Andy.Macrae@Corp.Sun.COM (Andrew MacRae)
Message-ID: <9304051847.AA05710@grendal.Corp.Sun.COM>
To: srgxnbs@grace.cri.nz
Subject: Re: I^2C bus and long haul serial (also Axlo
CC: Andy.Macrae@Corp.Sun.COM
content-length: 693
In article <1pii04INNk6t@zephyr.grace.cri.nz> you write:
> Whats required to get onto the ACCESS bus? The nice thing about the
> i2c is that most i/o requires one 8 ... 16 pin DIL chip, ie its cheap
> and easy. Anyone can design a bus, trouble is most buses require a
> host of interface chips and often on-board intelligence.
Bruce,
For the latest information on Access.Bus call the Access.Bus
Industry Group at (408) 991-3517.  Also, Sun will be hosting the next
meeting of the group on April 19th, here in Mountain View.  For some reason
I am not able to post to any newsgroups today, so please feel free to pass
this information on yourself as you see fit.
Andrew MacRae
From: baden@sys6626.bison.mb.ca (baden de bari)
Subject: Re: Jacob's Ladder
Organization: System 6626 BBS, Winnipeg Manitoba Canada
Lines: 36
g92m3062@alpha.ru.ac.za (Brad Meier) writes:
> Hi, I'm looking for a circuit, that is called a "Jacob's Ladder".
> This little box is usually seen in sci-fi movies.  It consists of
> two curves of wire protruding into the air, with little blue sparks
> starting at their base (where the two wires are closer to each other),
> moving up the wires to the top, and ending in a small crackling noise.
>
> Could anyone supply me with the schematic for the innards of this box?
>
> Thanks in advance
> Mike
>
> (Please reply by email to g90k3853@alpha.ru.ac.za)
>
> --
>  |  / |  | ~|~ /~~\  |  | ~|~ /~~\  |~~\  /~~\         The KnightOrc
>  |/   |\ |  | |   __ |__|  | |    | |__/ |         g92m3062@hippo.ru.ac.za
>  |\   | \|  | |    | |  |  | |    | |  | |      "When it's over I'll go home,
>  |  \ |  | _|_ \__/  |  |  |  \__/  |  |  \__/    until then, I stay!" - Me
I'd like any accumulated information on this as well please.
Thanks.
_________________________________________
_____                                |
|     |   |                           |
=========== |    Baden de Bari          |
| o   o |  |                           |
|   ^   |  | baden@sys6626.bison.ca    |
|  {-}  |  | baden@inqmind.bison.ca    |
\_____/   |                           |
-----------------------------------------
From: schellew@wu2.wl.aecl.ca (Wayne Schellekens)
Subject: WANTED: DRAM Controller for use with MC68HC16
Keywords: DRAM, HC16
Nntp-Posting-Host: wu2.wl.aecl.ca
Organization: AECL Research, Whiteshell Laboratories
Distribution: na
Lines: 25
For an upcoming project I want to use 4 Megs of DRAM configured as two 2
Meg banks of 16 bit data.  I was wondering if anyone out there knows of a
DRAM controller which will handle refreshing the data.  It's ok if the
controller doesn't handle bank switching - that part is easy.
The only controllers I know of are the ones out of the National
Semiconductor DRAM Management Handbook (1988 edition) eg. DP8429.  I would
like to know if another manufacturer produces one which may be easier to
implement in my circuit.
BTW, if anyone is wanting to hook up DRAM to a microcontroller, Dallas
Semiconductor makes a neat chip: the DS1262 Serial DRAM Nonvolatizer
Chip.  It uses the SPI (I2C) bus and refreshes/controls up to 16Mx1 of DRAM
memory.  It can use an external battery to refresh the DRAM when the
power is off.  Price is $11.75 from Dallas (quan 1).  I wish I could use
this chip but its maximum SPI clock rate is 1 MHz (too slow for me...).
Thanks in advance,
Wayne Schellekens
<schellew@wu2.wl.aecl.ca>
--
Wayne Schellekens, VE4WTS          Internet: schellew@wu2.wl.aecl.ca
AECL Research                         AX.25: VE4WTS@VE4KV.#WPG.MB.CAN
Whiteshell Laboratories        Twisted pair: (204)753-2311 x2317
From: vanderby@mprgate.mpr.ca (David Vanderbyl)
Subject: Re: HV diodes
Nntp-Posting-Host: chip
Reply-To: vanderby@mprgate.mpr.ca (David Vanderbyl)
Organization: MPR Teltech Ltd.
Lines: 15
In article <1pohuq$4sq@grouper.mkt.csd.harris.com>, wdh@grouper.mkt.csd.harris.com (W. David Higgins) writes:
|> I believe the only thing that needs correction, Mr. Vanderbyl, is your
|> attitude.
Nope, Mr. Myers has found the bad mistake and posted a correction, thank God.
|> Acting the child won't gain you any favors or make a
Who's acting?
|> positive impression with anybody.  Ghod knows you've make an impression
|> on me;  just not a positive one.
Oh no, I haven't impressed Mr. Higgins.
From: rajan@cco.caltech.edu (Rajan Ranga)
Subject: An external timer
Article-I.D.: gap.1pli7gINNi6b
Organization: California Institute of Technology, Pasadena
Lines: 8
NNTP-Posting-Host: fleming.caltech.edu
I was wondering if anyone knows of a chip that that is similar to
the internal timer 0 on the Intel 80C188?  I want a timer that has
a Maxcount A and B and the output should the same as Intel's timer.  I called
Intel and they told me that they don't make such a chip.  Any suggestions
are welcome.  Thanks in advance.
Rajan Ranga
E-mail: rajan@cco.caltech.edu
From: schuch@phx.mcd.mot.com (John Schuch)
Subject: Re: Re Using old databooks
Nntp-Posting-Host: bopper2.phx.mcd.mot.com
Organization: Motorola Computer Group, Tempe, Az.
Lines: 23
In article <1993Apr3.110048.4636@hemlock.cray.com> kilian@cray.com (Alan Kilian) writes:
>> jeh@cmkrnl.com
>
>This is almost exactly the reason I keep only the latest databook around.
>Too many times last years books turn into three years ago and the data
>in them doesn't match the current production parts.
>TANSTAAFL,
>                             -Alan Kilian
BUT... If you are in the habit of trying to repair old and obsolete
machines, the old data books are a goldmine of information you can
not get anywhere else. If you are trying to find a modern replacement
for an obsolete part, the original specs really come in handy. Design
out of the new books but save the old ones (or donate them to a ham).
If anybody in Phoenix disagrees, I'll drive over and help them 'get rid'
of all their old data books.
John
(450 data books and growing)
From: timd@fenian.dell.com (Tim Deagan)
Subject: Homebuilt PAL (EPLD) programer?
Nntp-Posting-Host: fenian.dell.com
Reply-To: timd@fenian.dell.com
Organization: SLAMDANZ CYBRNETX
Lines: 13
Anyone know a reasonable circuit for programming PALs?  I am interested
in programming a wide range of EPLDs but would be happy with something
that could handle a 22V10 or thereabouts.
Thanks in advance,
--Tim
---
{{{{{{{{{{{{{{{{{{{{{ timd@fenian.dell.com }}}}}}}}}}}}}}}}}}}}}}}}}}}}
Rev. Tim Deagan - Official Obnoxious Poster
No one but me is responsible for anything I write, believe in or preach
* "It is difficult to free fools from chains they revere." - Voltaire *
From: robert.desonia@hal9k.ann-arbor.mi.us (Robert Desonia)
Subject: A/D board BUS SPEED probl
Distribution: world
Organization: HAL 9000 BBS, W-NET HQ, Ann Arbor, Michigan, USA
Reply-To: robert.desonia@hal9k.ann-arbor.mi.us (Robert Desonia)
Lines: 39
C >Hi:
C >I have a 486DX2-66MHz computer to use with an A/D board
C >for data acquisition on an AT bus...I'm having problems.
C >The AT bus runs at 12.5 MHz - correct?  So there should
C >be no bus speed conflict. But I read somewhere that the
C >new 486DX2-66 MHz CPU runs on a 33 MHz bus - is that for
C >the local bus or the AT bus also - if so then I have a problem.
C >^^^^^^^^^^^^^^^^^^^^^^^^^^^
C >When I run on non-turbo-mode the speed goes to 8 MHz and the
C >A/D doesn't work.  Please mail your views!  Thanks.
C >Vincent
C >cyl5@musica.mcgill.ca
C >
The STANDARD AT bus (ISA) runs at 8MHz, not 12.5 MHz, but some
non-stnadard ISA buses do have higher clock rates, but be careful, since
some boards don't work with faster than standard rates.  For instance, my
486 has adjustable AT bus speeds, and my PAS16 audio card chokes when I do
AD data acquisition with a bus speed faster than 10MHz.
The fact that non-turbo-mode speed A/D doesn't work is weird.  You may
have a motherboard with a hardware 'bug'.
33 MHz bus on the 486DX2 66 does refer to the local bus.  FYI: the AT bus
operates asynchronously, and is linked to the local bus via a 'bus
interface', which is one function that your 'chipset'.
-rdd
---
. WinQwk 2.0b#0 . Unregistered Evaluation Copy
* KMail 2.95d W-NET HQ, hal9k.ann-arbor.mi.us, +1 313 663 4173 or 3959
----
| HAL 9000 BBS:  QWK-to-Usenet gateway  | Four 14400 v.32bis dial-ins    |
| FREE Usenet mail and 200 newsgroups!  | PCBoard 14.5aM * uuPCB * Kmail |
| Call +1 313 663 4173 or 663 3959      +--------------------------------+
| Member of EFF, ASP, ASAD  * 1500MB disk * Serving Ann Arbor since 1988 |
From: robert.desonia@hal9k.ann-arbor.mi.us (Robert Desonia)
Subject: Re: PC Parallel I/O
Distribution: world
Organization: HAL 9000 BBS, W-NET HQ, Ann Arbor, Michigan, USA
Reply-To: robert.desonia@hal9k.ann-arbor.mi.us (Robert Desonia)
Lines: 24
R >>>JD> ALL PC parallel ports that are compatable with the IBM standard,
R >>>JD> including the original IBM adaptor, are bi-directional.
NOT ALL PARALLEL PORTS ARE BI-DIRECTIONAL WITHOUT MODIFICATION.
My experience with the standard old zenith parallel port in their
original 286s proves that.  They had the input direction disactiviated by
tieing them R/W select line of the circuit to Vcc.  To make it bi ( which
I did ) I had to modify it by scraping off the trace and solder a jump to
the proper location.  I thought that this was just lazy on the part of
Zenith ( they were not Zenith-Bull Group at that time).
-rdd
---
. WinQwk 2.0b#0 . Unregistered Evaluation Copy
* KMail 2.95d W-NET HQ, hal9k.ann-arbor.mi.us, +1 313 663 4173 or 3959
----
| HAL 9000 BBS:  QWK-to-Usenet gateway  | Four 14400 v.32bis dial-ins    |
| FREE Usenet mail and 200 newsgroups!  | PCBoard 14.5aM * uuPCB * Kmail |
| Call +1 313 663 4173 or 663 3959      +--------------------------------+
| Member of EFF, ASP, ASAD  * 1500MB disk * Serving Ann Arbor since 1988 |
From: laird@pasture.ecn.purdue.edu (Kyler Laird)
Subject: Re: Telephone on hook/off hok ok circuit
Organization: Purdue University Engineering Computer Network
Lines: 6
These circuits abound in most electronic project books.  If you're more
inclined to buy something, try Radio Shack.  I think they still have a
device that is designed to disconnect an answering machine when an
extension line is lifted.  It has LED indicators also.
--kyler
From: jeh@cmkrnl.com
Subject: Re: Police radar....Just how does it work??
Distribution: sci.electronics
Organization: Kernel Mode Systems, San Diego, CA
Lines: 14
In article <afgE02Wb3dVu01@JUTS.ccc.amdahl.com>,
dws30@p1ps110cd.amdahl.com (David Sharpe) writes:
> There are a few more details to radar and some
> rumors that are not true.  A common one is that two beams are sent one
> reading the car speed and one the ground speed.  If this were true then
> calabration would be murder.  Hope this helps (Flame On)
Gee, then I guess the extra horn that's mounted in the floor of some SDPD cars,
firing at the ground at a shallow angle, is just for show, huh?
(For calibration, they simply turn off one horn or the other.)
--- Jamie Hanrahan, Kernel Mode Systems, San Diego CA
Internet:  jeh@cmkrnl.com  Uucp: uunet!cmkrnl!jeh  CIS: 74140,2055
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Subject: Re: Log/stereo high quality pot (hi-fi)
Organization: NASA Langley Research Center and Reptile Farm
Lines: 20
NNTP-Posting-Host: grissom.larc.nasa.gov
In article <1993Apr5.172839.22714@eng.cam.ac.uk> cmh@eng.cam.ac.uk (C.M. Hicks) writes:
>cobust@seagoon.ee.sun.ac.za (Cobus Theunissen) writes:
>
>>Hi there,
>
>>I am looking for a high quality log/stereo 10k pot for an audio
>>preamplifier.  The design specifies Alps RKGA-2 10k AX2, but I cannot
>>find it anywhere!  Any suggestions?
>
>The best pots around (IMHO) are made by Penny & Giles in the UK. Their
>basic model has a solid brass case, and conductive plastic elements
>matched to 0.5dB across the whole rotation. The downside is that they
>cost upwards of 50 quid each :-(
The P&G pots are very good.  The Alps ones are usually carried by
the same folks who run the Audio Amateur magazine.
I'll also recommend the Noble potentiometers, if you don't mind weird
metric sizes on everything.
--scott
From: msunde01@mik.uky.edu (Mark  Underwood)
Subject: Re: Police radar....Just how does it work??
Nntp-Posting-Host: nx35.mik.uky.edu
Reply-To: msunde01@mik.uky.edu
Organization: University Of Kentucky, Dept. of Math Sciences
Lines: 32
In article <1pqb8aINN9vg@hp-col.col.hp.com> cab@col.hp.com (Chris Best)
writes:
>
> The manual also got into the "cosine effect", wherein the motorist
> always gets the benefit of the doubt (effectively).  Depending on
> relative directions of the radar gun and target car, the reading
> will always be THE SAME AS or LOWER THAN the actual speed of the car.
> Never higher.
>
> And always remember that the cop doesn't even need radar to ticket you.
> His (her?) word as a skilled observer is enough.
The father of a friend of mine is a police officer in West Virginia.  Not
only is his word as a skilled observer good in court, but his skill as an
observer has been tested to be more accurate than the radar gun in some
cases . . ..  No foolin!  He can guess a car's speed to within 2-3mph just
by watching it blow by - whether he's standing still or moving too!  (Yes,
I realize that calibrated guns are more accurate than this, but . . .).
His ability is not that uncommon among people who watch moving things for a
living, I have heard . . ..
So what good is a radar detector except to give you a split second warning
that the guy who just cut you off to pass the guy ahead and to your left
is about to panic stop from 85 on a crowded freeway???
Mark S. Underwood
EE Student, University of Kentucky
Lab Assistant, Boyd Hall Microlab
(a tiny little division of UK Library Microlabs)
E-Mail:  msunde01@mik.uky.edu
From: wellison@kuhub.cc.ukans.edu
Subject: Re: Help with ultra-long timing
Organization: University of Kansas Academic Computing Services
Lines: 33
Thanks for the resposes as they were all good ideas and I am looking at using a
couple of the ideas. I recieved in the mail today the spec sheets on the mil.
spec version of Exar's XR-2240 timer/counter chip. It is stable down to -50 C
and sucks very little power. They show an application for a ultra-long time
delay (up to several years depending on the RC time constant). In this
application, they have two of them cascaded together. The reset and trigger
pins of both chips are tied together and the timebase of the second chip is
disabled. In this configuration, the output is high when the system is reset.
When triggered, the output goes low and stays that way for a total of 65,536 x
the timing cycle of the first chip. The total timing cycle of the two chips can
be programmed from To = 256 x R x C to 65,536 x R x C in 256 steps by selecting
any combination of the counter outputs to the timer output. The beauty of it
is, the timebase chip would only have to have a 100uF timing cap and a 391K
resistor for 39.1 seconds per timing cycle. So I can get a maximum of
2,562,457.6 seconds between timing cycles (39.1 x 65,536 or about 29 days !)
Of course, that's much more than I need (14 days). But the counter allows for
256 binary steps that can be selected for the output for the 'pellet puker'.
After the first 14 days and it trips, it would reset its self for the next 14
day timing cycle and so forth.
Power is still a problem though. A few ideas that you suggested was to bury the
electronics in a hole dug in the snow (as an insulator) and put the pellet
puker up on a tower above the estimated snow fall with a solar panel on it to
keep a charge on a lithium battery pack. I like that idea ;-) This thing has to
work for at least six weeks for three samples and the gas valves are 12 volts
to spit the pellets out onto the snow. Anyway, I ordered the XR-2240's to see
what I can do with them. Should be interesting (as long as I'm not the one that
has to go digging up the pellets in the middle of Antartica freezing my buns
off ;-)
Thanks again everyone...
-=-= Wes =-=-
From: cph@dmu.ac.uk (Chris Hand)
Subject: Re: PC Based Layout Program
Organization: De Montfort University, Leicester, UK
Lines: 26
X-Newsreader: TIN [version 1.1 PL8]
Frank Hielscher (hielsche@aragorn.CSEE.Lehigh.Edu) wrote:
: The PADS*.ZIP files contain subdirectories, and have to be unzipped
: via "pkunzip -d". Then an xcopy /s to three floppies creates the disks
: needed to do the install.
I'm still not sure how this is supposed to work, since the .ZIP files
took up about 2.5Mb, so it must be a tight squeeze on those floppies...
However, I managed to install PADS and I'm pretty impressed.  I created
a couple of schematics without problem, but whenever I try to
create a PCB layout from one of *my* circuits (rather than the demos)
it doesn't work.  I'm wondering if maybe a file isn't where it should
be...
Can anyone who has a printed manual comment on whether the registration
fee is worth paying?
Chris
--
Chris Hand, Lecturer                Internet mail: cph@dmu.ac.uk
Dept of Computing Science,          Voice: +44 533 551551 x8476
De Montfort University, The Gateway,  Fax: +44 533 541891  FIDOnet: 2:440/32.50
LEICESTER, UK   LE1 9BH             >> Linux: *free* unix for IBM PCs! <<
Subject: Re: Principle_of_the_Breathalyzer
From: srgxnbs@grace.cri.nz
Organization: Industrial Research Ltd., New Zealand.
NNTP-Posting-Host: grv.grace.cri.nz
Lines: 3
In NZ apparently things like aftershave are also giving positive
readings
From: rainer@spot.Colorado.EDU (Rainer Malzbender)
Subject: Re: HC11 blues -> no can find
Nntp-Posting-Host: spot.colorado.edu
Organization: University of Colorado, Boulder
Lines: 10
In article <pat.734048757@fegmania.wustl.edu> pat@fegmania (Patrick Niemeyer) writes:
>I too had trouble finding hc11's when I looked for them a while back.
>I'd be interesting in hearing if anyone knows about their availability now...
The newest JDR Microdevices catalog has at least one variant of the HC11.
--
Rainer M. Malzbender
Fyzzicks, CU Boulder
(303)492-1366
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: Oscilloscope triggering
Organization: Macquarie University
Lines: 86
Distribution: world
NNTP-Posting-Host: macadam.mpce.mq.edu.au
In article <1993Apr5.120921.28985@dxcern.cern.ch>, jeroen@dxcern.cern.ch (Jeroen Belleman) writes:
|> In article <C4vs0G.5ux@murdoch.acc.Virginia.EDU> dgj2y@kelvin.seas.Virginia.EDU (David Glen Jacobowitz) writes:
|> >	Is it just me, or does anybody else out there NOT like digital
|> >scopes. My school has ...
|> >
|> >					David Jacobowitz
|> >					dgj2y@virginia.edu
|>
|> Oh no you're not the only one. Analogue scopes give you (or me, at
|> least) a fair idea of what's going on in a circuit. Digital scopes
|> seem to have a habit of inventing a sizable part of it. E.g. even
|> when there are only a few samples per period, our HP54510A displays a
|> continuous waveform, complete with non-existing overshoots. I've
|> waded through lots of manual pages and menus, but I haven't found yet
|> how to turn this off. It doesn't show which points have actually
|> been measured, as opposed to those which have been interpolated,
|> either.
Perhaps you're using the wrong brand! (Sorry all HP fans, but I have
a hard time being convinced that their scopes match the rest of their
(excellent) gear).
One of the principal functions I look for when considering a DSO is
whether you can turn interpolation off. The other important feature
is to disable repetitive waveform acquisition i.e. being able to lock
the instrument into real time capture mode.
|>
|> Secondly, I don't like menus. I want to see all common functions
|> with their own button. (You'll have guessed I love analogue Tek
|> scopes) I'd choose a knob with printed legend over an on-screen
|> display with up-down buttons right away. The single knob of most
|> digital instruments never seems to be connected to the right function
|> at the right moment.
|>
I agree with you here. The only consolation is that manufacturers are
_beginning_ to pay attention to ergonomics when designing the menus.
However, to be fair, it seems that first time scope users (our students)
seem to adjust to menus easier than navigating around the twenty or
more knobs required of a "real" scope :-)
|> Last but not least, you never know if the waveform displayed is old
|> or recent, noisy or just incoherently modulated, heck, you don't
|> even know if it really looks the way it's displayed. Digital scopes
|> only show you a tiny fraction of what's going on. Most of the time
|> the're busy computing things.
This is one area that newer DSOs are addressing. I recently evaluated
the latest box from Tek - their TDS320 - which seems to be a worthy
alternative to a standard 100MHz analogue CRO. This instrument has
a 100MHz, 500Ms/s spec, meaning that it is _always_ in real time
capture mode. The pricing also matches equivalent analogue scopes in
the range. The downer is that the instrument uses menus again, but at
least they appear to be logically laid out.
|>
|> There are only three situations for which I would prefer a digital
|> scope: Looking at what happened before the trigger, looking at rare
|> events, and acquiring the data to have my computer play with it.
|>
|>
|> Let's hope scope manufacturers are listening...
|>
|> Best regards,
|> Jeroen Belleman
|> jeroen@dxcern.cern.ch
One more thing about the new, "simpler", front panels. These instruments
tend to use digital rotary encoders as knobs now. This is a vast improvement
over the old oak switch. The single most common cause of failure in our
scopes (other than students blowing up inputs!) is mechanical wear on these
switches. I look at the new panels as a great step toward increasing the
longevity of the instruments.
JohnH
----------------------------------------------------------------------------
|  _  |_   _   |_|  _   _|  _|              Electronics Department
|_| (_) | | | |  | | (_| (_| (_| \/           School of MPCE
---------------------------------/-           Macquarie University
Sydney, AUSTRALIA 2109
Email: johnh@mpce.mq.edu.au, Ph: +61 2 805 8959, Fax: +61 2 805 8983
----------------------------------------------------------------------------
From: rob@dexter.psych.umn.edu (Robert Stephens)
Subject: Compressor Problem
Nntp-Posting-Host: dexter.psych.umn.edu
Organization: University of Minnesota
Lines: 18
I have a stereo compressor-limiter by
Audio Logic (Model MT-66).  The gates work,
but the compressor seems to be gone on one
channel, and very weak on the other.
I'll probably need an ocsilloscope to trace it
down (no pun intended), but if any one with
experience with this type of equipment could
point me in a certain direction as to where the
circuit is most likely to fail, I'd sure appreciate it.
--
Robert C. Stephens		rob@dexter.psych.umn.edu
Human Factors Research Lab
University of Minnesota
From: neale@ee.rochester.edu (Reg Neale)
Subject: Pioneer Laser player
Organization: Univ of Rochester, College of Engineering and Applied Science
Lines: 5
I'm trying to figure out how to operate a Pioneer Laserdisc LD-1000 that I bought at a surplus store. It is reputedly from some kind of computerised viewing
and/or ordering system. THere is what may be an HPIB connector on the back. When
I power it up, the front panel power light comes on, but no activity, and the
door doesn't open. Anyone have any experience with this unit or any ideas on how
to obtain documentation?
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: Help with ultra-long timing
Organization: Macquarie University
Lines: 60
Distribution: world
NNTP-Posting-Host: macadam.mpce.mq.edu.au
In article <1993Apr5.083324.48826@kuhub.cc.ukans.edu>, wellison@kuhub.cc.ukans.edu writes:
|> I have a project that was drooped in my lap that is somewhat a pain to design.
|> What I am looking for is a stable ultra-long solid state timer. What they want
|> to do is to place this thing on the Antartic ice shelf and measure the amount
|> of snow fall over a period of six weeks. Every two weeks, they want to trip a
|> selonoid to discharge different colored pellets by gas pressure out across the
|> snow. Then by digging down into the snow, the snow fall amount can be measured
|> as they come to the different color pellets.
|>
|> The problem is trying to build a timer that would stand the cold (-40 degrees)
|> and a power source that wouldn't drain. I have looked at the XR-2204 timers and
|> the standard NE556 dual timers, but thier temp specs won't go that low. Also,
|> two weeks equates to 1,209,600 seconds per firing, which means one big timing
|> cap ! I have found 2.2 farad (yes, Farad !) caps that have a working voltage of
|> 5 volts and are small in size. But again, the time of discharge at -40 or lower
|> degrees isn't linear. I was thinking of using several timers chained together
|> to fire the selonid at the end of the timing period, but that blasted cold and
|> the drain on a battery over six weeks is the pain. One possibility would be to
|> use solar panels, but this is during the six month twilight. Anyone have any
|> good ideas ?
|>
|> Thanks in advance...
|>
|> -=-= Wes =-=-
Firstly, I would never consider trying to make a one-shot timer. Your 2F2 cap
will have been designed as a RAM battery substitute, rather than for use in
applications where you wish to drain the cap with a constant current. Their
performance, in some respects, is more akin to batteries than to a normal cap.
The other point is that big electro's are usually rated with -5%+20% tolerances,
so calculating exactly what capacitance you have (particularly when considering
the cold).
You should be looking at designing a micropower oscillator and divider chain,
that "rolls over" (from zero to maximum count, or vice-versa) once every
1,209,600 seconds. If you were to use something like a 110Hz clock, you would
need a divider chain of 2^27, to give an error of less than one percent in the
firing times over the six week period. Of course, you could trim the 110Hz
oscillator to give you exact time, but the likelyhood of the oscillator
remaining exactly constant at -40 is low anyway.
I would suspect that there would be far more battrey drain in firing the
solenoid than there would be in the timer circuit.
Caveat - I'm not experienced in low temperature electronics, so I can't
guarantee that this (or any other) approach is the best for inhospitable
conditions.
JohnH
----------------------------------------------------------------------------
|  _  |_   _   |_|  _   _|  _|              Electronics Department
|_| (_) | | | |  | | (_| (_| (_| \/           School of MPCE
---------------------------------/-           Macquarie University
Sydney, AUSTRALIA 2109
Email: johnh@mpce.mq.edu.au, Ph: +61 2 805 8959, Fax: +61 2 805 8983
----------------------------------------------------------------------------
From: engp2254@nusunix1.nus.sg (SOH KAM YUNG)
Subject: Re: Protection of serial (RS232) lines
Organization: National University of Singapore
X-Newsreader: TIN [version 1.1 PL6]
Lines: 39
Martin John Gregory (mgregory@flash.pax.tpa.com.au) wrote:
: I've started to look at some devices doing serial data transmission
: over fairly decent distances in fairly noisy environments, and have
: seen a variety of schemes for protecting the RS232 transceivers (and
: the rest of the circuit) from transients on the serial lines.  I'm
: left wondering what is the best way of doing this?  How necessary is
: it?
: [stuff deleted]
: What is the wisdom on this out there?
:
: Ta,
:
: Martin.
:
:
From what I know, protection is necessary, esp. if you plan to route
the cables into an unknown environment (out of your control). Things
like accidental shorts between the signal lines and power cables, or
even lightning strikes are very likely and I don't think you like to see
the sight of your computer going up in smoke! [Even ethernet cards are
protected. I've looked at the one in my PC and the connector is
protected by a gas discharge tube!]
{But if you plan to use the serial cables for internal routings (i.e. in
controlled environments), it should be reasonably safe not to have
them.}
Suggestion: look in the RS data book. They have several RS232
transceivers that have overvoltage protection. Among them include the
LT1080, LT1081 and MAX250 and MAX251. The Maxims are suppose to be
electrically isolated ones but still need opto-isolators to work (don't
ask me why. I've never used them before.
Another alternative is an RS232 surge protector. Two are listed in the
RS catalogue. If you need additional info (i.e. stock nos.), just e-mail
me.
Soh Kam Yung,
engp2254@nusunix1.nus.sg
From: john@gu.uwa.edu.au (John West)
Subject: Re: Protection of serial (RS232) lines
Keywords: serial protection
Article-I.D.: uniwa.1pqp7f$h16
Organization: The University of Western Australia
Lines: 13
NNTP-Posting-Host: mackerel.gu.uwa.edu.au
laird@stable.ecn.purdue.edu (Kyler Laird) writes:
>There is at least one optically-isolated RS-232 transceiver chip.  I
>don't remember where I saw it.
RS Components (they exist in Australia and the UK. Don't know about the US) have
little chips called Isolated MAX 250 and 251. They give you isolated RS-232 from
a single 5V supply. External components are 4 caps, 4 optoisolators, a diode,
and an isloting transformer. They go up to 19.2K baud..
John West
--
For the humour impaired: Insert a :-) after every third word
From: rkim@mars.uucp (Richard H.S. Kim)
Subject: Need sources for HV capacitors.
Article-I.D.: nic.1993Apr5.213718.4721
Distribution: usa
Organization: Triacus Inc.
Lines: 26
Nntp-Posting-Host: mars.calstatela.edu
Recently, my video monitor went dead, no picture, some low distorted sound.
I didn't hear the tell-tale cracking that indicated HV at work, nor are the
filaments at the far end of the tube glowing orange, just nothing.
On examining the power board, I noticed the largest capacitor with a very
bad bulge at the top.  Naturally, I want to replace it, but I can't find
any sources.
The electrolytic capacitor is 330 mF at 250WV.  It has radial leads, and is
roughly 1 1/2 inches long, 1 1/8" wide.  The dimensions are important since
the whole board fits in a metal cage, leaving little room.
Living in the Los Angeles area, I've been to numerous stores (Dow Radio,
All Electronics, ITC Elect, Sandy's, Yale Elect) with empty hands.
Can anyone suggest sources for high-voltage capacitors?  Mail order is
fine, although I'd rather check out a store to compare the can.  I'm going
to try a video electronics store, hopefully they'll have HV caps.
(By the way, the monitor is a ATARI SC1224, Goldstar circuitry, Masushita
tube.  Anyone else had problems?)
Thanks in advance,
Rich K.
email>  rkim@opus.calstatela.edu
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: Help with ultra-long timing
Organization: Macquarie University
Lines: 39
Distribution: world
NNTP-Posting-Host: macadam.mpce.mq.edu.au
In article <C513wI.G5A@athena.cs.uga.edu>, mcovingt@aisun3.ai.uga.edu (Michael Covington) writes:
|> (1) Don't use big capacitors.  They are unreliable for timing due to
|> leakage.
|>
|> Instead, use a quartz crystal and divide its frequency by 2 40 times
|> or something like that.
|>
|> 1 MHz divided by 2^40 = 1 cycle per 2 weeks, approximately.
|>
|> (2) I wouldn't expect any components (other than batteries or electrolytic
|> capacitors) to fail at -40 C (or -40 F for that matter either :) ).
|> The battery is going to be your big problem.  Also, of course, your
|> circuit shouldn't depend on exact values of resistors (which a crystal-
|> controlled timer won't).
|>
... Wouldn't a crystal be affected by cold? My gut feeling is that, as a
mechanically resonating device, extreme cold is likely to affect the
compliance (?terminology?) of the quartz, and hence its resonant frequency.
|> --
|> :-  Michael A. Covington         internet mcovingt@ai.uga.edu :    *****
|> :-  Artificial Intelligence Programs       phone 706 542-0358 :  *********
|> :-  The University of Georgia                fax 706 542-0349 :   *  *  *
|> :-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :  ** *** **
JohnH
----------------------------------------------------------------------------
|  _  |_   _   |_|  _   _|  _|              Electronics Department
|_| (_) | | | |  | | (_| (_| (_| \/           School of MPCE
---------------------------------/-           Macquarie University
Sydney, AUSTRALIA 2109
Email: johnh@mpce.mq.edu.au, Ph: +61 2 805 8959, Fax: +61 2 805 8983
----------------------------------------------------------------------------
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: HC11 blues -> no can find
Organization: Macquarie University
Lines: 38
Distribution: world
NNTP-Posting-Host: macadam.mpce.mq.edu.au
In article <pat.734048757@fegmania.wustl.edu>, pat@fegmania (Patrick Niemeyer) writes:
|> ree88132@zach.fit.edu (Keith Ledig) writes:
|>
|> >was told by other people that it just takes a long time.  I heard
|> >rumors that the HC11 is very hard to get these days and is being
|> >replaced by the 711 series.  The sales person is trying to push
|> >the 711.  Can someone please tell me what is going on with these
|> >microcontrollers.  I can't seem to get a straight answer.
|>
|> I too had trouble finding hc11's when I looked for them a while back.
|> I'd be interesting in hearing if anyone knows about their availability now...
|>
|> Thanks,
|> Pat
The HC711 is an EPROM version of the HC11. Raw HC11 parts have factory set
ROM images, and as such are useless to the hobbyist. HC811 parts have
EEPROM, allowing for electrical erasure and reprogramming.
Some Motorola parts (such as the HC705K1) have EPROM, making them user
programmable, but come with options of either windowed or sealed. The
more expensive windowed packages allow multiple use, the plastic dip
varieties are one-time programmable, since there is no way of exposing
the EPROM array to light.
JohnH
----------------------------------------------------------------------------
|  _  |_   _   |_|  _   _|  _|              Electronics Department
|_| (_) | | | |  | | (_| (_| (_| \/           School of MPCE
---------------------------------/-           Macquarie University
Sydney, AUSTRALIA 2109
Email: johnh@mpce.mq.edu.au, Ph: +61 2 805 8959, Fax: +61 2 805 8983
----------------------------------------------------------------------------
From: tg@cs.toronto.edu (Tom Glinos)
Subject: 12V to 3V and 48V at 3A
Organization: Department of Computer Science, University of Toronto
Distribution: na
Lines: 11
The subject line says it all. I'm working on a project
that will use a car battery. I need to pull off 3V and possibly
48V at 3A.
I have several ideas, but I'd prefer to benefit from all you
brilliant people :-)
--
=================
"Conquest is easy, control is not"	| Tom Glinos @ U of Toronto Statistics
[Star Trek TOS]   			| tg@utstat.toronto.edu
USL forgot this simple history lesson
From: Wayne Alan Martin <wm1h+@andrew.cmu.edu>
Subject: Re: Help with ultra-long timing
Organization: Senior, Electrical and Computer Engineering, Carnegie Mellon, Pittsburgh, PA
Lines: 7
Distribution: world
NNTP-Posting-Host: po4.andrew.cmu.edu
In-Reply-To: <1pqk9b$ib4@sunb.ocs.mq.edu.au>
Sounds like a job for a universal time reciever.  I don't know the
logisitics of the situation, but if you could just place a reciever in
snow and place the oscillator in a nice lab somewhere else, your
problems should be solved.
Just a suggestion.
Wayne Martin
From: kthompso@donald.WichitaKS.NCR.COM (Ken Thompson)
Subject: Re: 68HC11 problem
Organization: NCR Corporation Wichita, KS
Lines: 21
mdanjou@gel.ulaval.ca (Martin D'Anjou) writes:
B
)>>>>>>>>> Votre host est mal configure... <<<<<<<<<<<<
)Bonjour Sylvain,
)	J'ai travaille avec le hc11 il y a 3 ans et je ne me souviens pas de toutes les possibilites mais je vais quand meme essayer de t'aider.
)	Je ne crois pas que downloader une programme directement dans le eeprom soit une bonne idee (le eeprom a une duree de vie limitee a 10 000 cycles il me semble). Le communication break down vient peut-etre du fait que le eeprom est long a programmer (1ms par 8 bytes mais c'est a verifier) et que les delais de transfer de programme s19 vers la memoire sont excedes. Normalement, les transferts en RAM du code s19 est plus rapide car le RAM est plus rapide que le eeprom en ecriture.
)	C'est tout ce que ma memoire me permet de me souvenir!
)Bonne chance,
Oh yeah easy for him to say!...
--
Ken Thompson    N0ITL
NCR Corp.  Peripheral Products Division   Disk Array Development
3718 N. Rock Road  Wichita KS 67226   (316)636-8783
Ken.Thompson@wichitaks.ncr.com
From: whit@carson.u.washington.edu (John Whitmore)
Subject: Re: Wire wrap questions (again?)
Article-I.D.: shelley.1pr803INNh8e
Organization: University of Washington, Seattle
Lines: 36
NNTP-Posting-Host: carson.u.washington.edu
In article <PASCAL.93Apr1160623@ap10.apd.cpg.sony.co.jp> pascal@apd.cpg.sony.co.jp (Pascal Goguey) writes:
>In article <7376@blue.cis.pitt.edu> macfitz+@pitt.edu (Mark D Fitzsimmos) writes:
> *After a considerable amount of research, review of discussions
> *on this group, and mainly fruitless time on breadboards, I have
> *decided that the path of least resistance for prototyping my (not
> *necessarily someone else's) electronic designs is wire wrapping.
>	I have no idea about what you want to do, but be careful :
>Wire wrapping increases a lot the wiring capacitance. That shouldn't
>be a problem for "slow" applications (i.e a few MHz), but as for
>quicker ones (around 30 / 40 MHz), I doubt that it can work.
Fortunately, wire-wrapping is a better wiring technique than
most at high frequencies; Cray computers (up to the X-MP, at least)
all had wirewrapped backplanes.  Wirewrap gets into trouble at
much higher frequencies than any TTL can handle.  The 'increase'
of wiring capacitance is not really relevant (you have to use
transmission line techniques, and the capacitance is no problem).
> *1) Where can I get a decent wrapping tool?  I'd like to spend less
> *than $150 for an AC powered unit including bit and sleeve.
>	Hand powered is the best. There are good AC powered ones,
>but rather expensive. A low-cost one doesn't work very well.
Hand-powered is a terrible choice (IMHO) unless you are
a field maintenance person who will do maybe a dozen connections
at a time.  Your hands will cramp.  Battery-powered wire-wrap guns
are available in the $150 range, and so are the little
twiddle-stick manual types ($15).  For a modest project, of
a couple hundred connections, I'd prefer to borrow a professional
AC unit... or a pneumatic one.
John Whitmore
From: jkeais@ucssun1.sdsu.edu (keais j)
Subject: Re: Pioneer Laser player
Article-I.D.: gondor.1pr8nn$46v
Organization: SDSU Computing Services
Lines: 17
NNTP-Posting-Host: ucssun1.sdsu.edu
In article <1993Apr6.005150.10250@ee.rochester.edu> neale@ee.rochester.edu (Reg Neale) writes:
>I'm trying to figure out how to operate a Pioneer Laserdisc LD-1000 that I bought at a surplus store. It is reputedly from some kind of computerised viewing
>and/or ordering system. THere is what may be an HPIB connector on the back. When
>I power it up, the front panel power light comes on, but no activity, and the
>door doesn't open. Anyone have any experience with this unit or any ideas on how
>to obtain documentation?
What you have is one of the LD players from a video game (Dragon's Lair,
Space Ace, etc). Call Pioneer Technicial Support 213-498-0300 (at least
that's the number I called them at) and ask for the LD-V1000 Interface
Guide. It shows how the parallel interface should be wired and the codes
for the commands (play, pause, reject, etc). The guide is mainly for hooking
the player to a computer, but with a little work, you could build a wired
controller.
Jim Keais        jkeais@ucssun1.sdsu.edu
From: whit@carson.u.washington.edu (John Whitmore)
Subject: Re: Help with ultra-long timing
Article-I.D.: shelley.1pr91aINNikg
Distribution: world
Organization: University of Washington, Seattle
Lines: 25
NNTP-Posting-Host: carson.u.washington.edu
In article <1pqu12$pmu@sunb.ocs.mq.edu.au> johnh@macadam.mpce.mq.edu.au (John Haddy) writes:
>In article <C513wI.G5A@athena.cs.uga.edu>, mcovingt@aisun3.ai.uga.edu (Michael Covington) writes:
>|> (1) Don't use big capacitors.  They are unreliable for timing due to
>|> leakage.
True (especially for electrolytic capacitors at high temperature).
>|> Instead, use a quartz crystal and divide its frequency by 2 40 times
>|> or something like that.
>... Wouldn't a crystal be affected by cold? My gut feeling is that, as a
>mechanically resonating device, extreme cold is likely to affect the
>compliance (?terminology?) of the quartz, and hence its resonant frequency.
Low power quartz oscillators are usually 32 kHz (and THESE
have significant temperature drifts, which one doesn't often notice
while wearing the watch on one's wrist).  Low temperature sensitivity
is available in other crystal types, which unfortunately
are larger and higher frequency (1 MHz or so) and take more
battery power.
Programmable timers might be less accurate, but they
are more power-stingy than suitable crystal oscillators.
John Whitmore
From: wa2ise@cbnewsb.cb.att.com (robert.f.casey)
Subject: 2 level brightness Xmas light set (for Easter?
Keywords: xmas
Organization: AT&T
Lines: 54
Yes, I know it's nowhere near Christmas time, but I'm gonna loose
Net access in a few days (maybe a week or 2 if I'm lucky), and wanted
to post this for interested people to save 'till Xmas.   :-(
Note: Bell Labs is a good place IF you have a PhD and a good boss, I
have neither.
--------------------------------------------------------------------------
Subject: Xmas light set with 2 levels of brightness
Another version of a variable brightness Xmas light set:
This set starts with a 2 blinker 35 bulb string.
DIAGRAM:  orginal 2 way set
120v---+--b-*-*-*-*-*-*-*--!
!---b-*-*-*-*-*-*-*-!
!
120rtn_____________________!
modified set for 2 level brightness:
string 1
120v---------*-*-*-*-*-*-*-*--!
\_10K_______*-*-*-*-*-*-*-*-!
5w    !      string 2     !
b   ________________!
120v rtn__!___!
^ Note: no mods to wiring to the right of this point.
Only one blinker is used.
Note that the blinker would not have as much current thru it as the
string 1 bulbs, because of the second string of bulbs in
parallel with it.  That's why the use of the 10K 5W resistor
here to add extra current thru the blinker to make up for the
current shunted thru the second string while the blinker is glowing
and the second string is not glowing.  When the blinker goes open,
this resistor has only a slight effect on the brightness of the
strings, s1 slightly dimmer, s2 slightly brighter.
Or use a 3W 120v bulb in place of the 10K resistor if you can get
one.  Caution, do not replace with a standard C9 bulb, as these
draw too much current and burn out the blinker.  C9 = approx 7W.
What you'll see when it's working:  powerup, string 1 will light
at full brightness, and b will be lit, bypassing most of the current
from the second string, making them not light.  b will open, placing
both strings in series, making the string that was out to glow at a
low brightness, and the other string that was on before to glow
at reduced brightness.
Be sure to wire and insulate the splices, resistor leads, and cut wires
in a safe manner!
From: blakey@ug.cs.dal.ca (Jason Blakey)
Subject: FTP sites anyone?
Nntp-Posting-Host: ug.cs.dal.ca
Organization: Math, Stats & CS, Dalhousie University, Halifax, NS, Canada
Lines: 7
Hello netters:)  Does anyone out there know any FTP sites for projects,
plans, etc of an electrical nature?
-Jason
--
............................................................................
Jason Blakey -> blakey@ug.cs.dal.ca
From: davidb@macadam.mpce.mq.edu.au (David Bull)
Subject: Intel RMX O/S Documentation Wanted
Organization: School of MPCE, Macquarie University, Australia.
Lines: 19
Distribution: world
NNTP-Posting-Host: macadam.mpce.mq.edu.au
Originator: davidb@macadam.mpce.mq.edu.au
We've just been donated a large machine for use in our
robotics lab. This device is complete with a 286 based
controller, running the Intel RMX operating system.
Unfortunately, we don't have any documentation on RMX.
Can anybody out there in netland help?
Please reply via email; I don't regularly catch up with
the news.
Thanks,
David Bull
davidb@mpce.mq.edu.au
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: Re: What is Zero dB????
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 81
In article <sehari.733764410@vincent1.iastate.edu>, sehari@iastate.edu (Babak Sehari) writes:
|> In <C4truE.6AA@ms.uky.edu> msunde01@mik.uky.edu (Mark  Underwood) writes:
|>
|> >I am somewhat familiar with the dB measurements as they apply to
|> >electrical circuits - i.e. it is the gain of (for example) an amplifier
|> >measured on a logarithmic scale.  However, this requires that you have a
|> >reference value:  i.e the ouput is +20dB (e.g.) with respect to the input
|> >signal.
<stuff deleted>
|> What you actually talking about here is dBm and not dB.  However, the terms
|> are used loosely by most people.  ``dBm'' is power with respact to 1mW, whereas
|> dB is a ratio.  Now, like these two English statement:
|>
|> 1.  I am doing well.
|> 2.  I am doing good.
|>
|> Similarly, people usually use dB for dBm. Another common mistake is spelling
|> ``db'' instead of ``dB'' as you did in your article. See the ``B'' is for
|> ``Bell'' company, the mother of AT&T and should be capitalized.
|>
|>                           With highest regards,
|>                                Babak   Sehari.
Good gravy! Decibels are all *ratios.* The question that remains in
any ratio is the reference unit used. Sometimes, this will be a reference
power, such as 1 milliwatt (given a certain circuit impedance which
should also be included in the fine print or known, like 50 ohms
in an RF circuit of that impedance), leading to an accepted
notation of dBm. Maybe it might be dBV, disregarding the impedance of
the circuit and power developed, using 1 volt as reference *amplitude*
(rather than reference power). Or, it might have an arbitrary or omitted
reference that is not included in the notation, leading to just plain dB.
So. look at it this way--'dB' has an implied reference while notation
such as 'dBm' has an explicit reference.
For power:
dB = 10*log( P(measured)/P(reference) )
For amplitude
dB = 20*log( A(measured)/A(reference) )
'B' is for bel, which is a standard term for a log ratio to the base
10, named after Alexander Graham Bell. A 'deci' Bel is 1/10 of a bel.
It has nothing to do with the Bell Telephone company except for
the common founder's name. The small 'd'/large 'B' is per SI notation
convention. I don't know anyone that's been crucified for messing it up.
Common references for audio are:
0 dBm = 1 milliwatt across 600 ohms
0 dBV = 1 volt
0 VU (a zero on the VU meter) = +4 dBm  (pro gear line level)
0 VU = -10dBV	(consumer gear line level)
Often times, a power amp VU meter will be aligned using
the rated power of the amp as the 0 dB point. It is all
done to whatever reference is reasonable for the application
or moment.
Note that in a circuit with a given (and maybe unknown) linear
impedance, if the amplitude goes up so many decibels, the
power will also increase the same amount. This proof can be done
with the above two identities and ohm's law.
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: Re: Flyback squeal in video monitors
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 41
In article <1993Mar31.204036.4359@ssc.com>, markz@ssc.com (Mark Zenier) writes:
|> Zack Lau (zlau@arrl.org) wrote:
|> : In sci.electronics, xhan@uceng.uc.edu (Xiaoping Han) writes:
|> : >In article <1993Mar24.163510.158@hubcap.clemson.edu> michaet@hubcap.clemson.edu (Michael D. Townsend) writes:
|> : >>brendan@macadam.mpce.mq.edu.au (Brendan Jones) writes:
|> : >>
|> : >>My mom's 25" Magnavox does this as well.  I put chewing gum all around
|> : >>the horizontal sync transformer so it wouldn't resonate the board as
|> : >>much.  Don't flame, it worked.  I realize that there is a more suitable
|> : >>substance available for this purpose, but I don't remember what and
|> : >>where it is.
|> :
|> : >Adhesive silicon, from hardware store.
|> :
|> : If it smells like vinegar, it may damage metal surfaces by
|> : promoting corrosion.
|>
|> Anybody tried Superglue (cyanoacrylate ?).  This should sneak
|> into the cracks better, and is stiffer than silicone.
I've found this works pretty well on noisy laminated power
transformer cores and windings (the 60Hz kind). Likewise, if
anybody has tried this on a flyback I'd like to hear about it.
I would suspect it would not be as effective as it was on power
transformers as the material wouldn't damp as well--something
I suspect would be critical at the frequencies involved (in other
words, you want absorption rather than prevention which would be
real difficult at 15 KHz).
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: ph@gmd.de (Peter Hendricks)
Subject: Re: Wanted: A to D hardware for a PC
To: ebuddington@eagle.wesleyan.edu
Nntp-Posting-Host: gmdzi
Organization: GMD, Sankt Augustin, Germany
Lines: 23
In <3889@ncr-mpd.FtCollinsCO.NCR.COM> Brad Wright writes:
>	If you know much about PC's (IBM comp) you might try the joystick
>port.  Though I haven't tried this myself, I've been told that the port
>has built in A-D converters.  This would allow the joystick to be a couple of
>pots.  If you could find the specs this might just work for you...
I guess 100k, connecting pins 1-3 (1x), 1-6 (1y), 9-11 (2x), and 9-13 (2y).
Or: Get an 8-bit DA-Converter (merely a couple of transistors and
Resistors) and an OpAmp to compare its output to the voltage you want to
measure, connect them to a spared printer port (if you have one), and do
the rest by software (stepwise refinement). The port addresses for your
printer ports are probably: &H378 (LPT1), &H278 (LPT2). This should work
well enough for your purposes.
Hope this helps
--
GMD,  Schloss Birlinghoven,  Postfach 1316,  D-5205 St. Augustin 1,  FRG
e-mail:  Peter.Hendricks@gmd.de			ph@zi.gmd.dbp.de
ph@gmd.de
From: kolstad@cae.wisc.edu (Joel Kolstad)
Subject: Re: Wanted: A to D hardware for a PC
Article-I.D.: doug.1993Apr6.053736.23113
Organization: U of Wisconsin-Madison College of Engineering
Lines: 22
>In <3889@ncr-mpd.FtCollinsCO.NCR.COM> Brad Wright writes:
>
>>	If you know much about PC's (IBM comp) you might try the joystick
>>port.  Though I haven't tried this myself, I've been told that the port
>>has built in A-D converters.  This would allow the joystick to be a couple of
>>pots.  If you could find the specs this might just work for you...
I believe that the "A-D converters" found on a joystick port are really
timers that tick off how long it takes an R-C circuit (the R being your
paddle) to charge up to something like 1/2 Vcc.  For games this works
pretty well, but you certainly wouldn't want to try to take lab
measurements off something as non-linear as that.
Hmm... I suppose you could linearize it in software, but the real problem
is that the precision of your measurement is no longer constant (higher
voltages would be more precise).
On the other hand, I could be wrong and perhaps the game card designers
splurged for the extra $.50 to make a cheap constant current source out of
an op amp.  But I wouldn't expect that...
---Joel Kolstad
From: rooi@duteca3.et.tudelft.nl (Mark de Rooi)
Subject: Calculating a transformer - help needed
Originator: rooi@duteca3.et.tudelft.nl
Nntp-Posting-Host: duteca3.et.tudelft.nl
Reply-To: rooi@duteca3.et.tudelft.nl (Mark de Rooi)
Organization: Delft University of Technology, Dept. of Electrical Engineering
Lines: 18
I want to convert a 500 Volt sinewave with frequency between 1 kHz
and 10 kHz, to a 10 Volt sinewave with the same frequency, by
means of a transformer. The secondary current will be .6 A (600 mA).
What kind of transformer should I use (ferrite?)
Can I buy one? If so, I need a partnumber and supplier
If I cannot buy one, how do I go about winding one myself?
What core do I use, how big must it be in order not to saturate,
what thickness copper wire, how many turns, etc.?
I know little about analog electronics, so I hope some kind
soul here will help me out.
Pointers to relevant databooks will also be highly appreciated.
Thanks,
Mark de Rooi
rooi@tpd.tno.nl
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: Re: HV diodes
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 36
In article <7480220@hpfcso.FC.HP.COM>, myers@hpfcso.FC.HP.COM (Bob Myers) writes:
|> > Nope.  The dag is on the outside of the tube, and is grounded.  The inside
|> > aluminization *is* the second anode, and is connected to the 'anode'
|> > suction cup.  This (with the glass of the tube in between) is a capacitor,
|> > and is used as the power supply bypass/filter for the HV supply.  Some
|> > smaller scope tubes don't have an aquadag coating on the outside.  If they
|> > are in mu-metal shields, you still have a capacitor.
|>
|> Actually (and I think I said this in the original, but perhaps wasn't clear
|> enough) there is usually both an internal AND an external dag.  Of the two,
|> the internal dag is the more important; the aluminization of the back of the
|> phosphor is in most cases not adequate to guarantee connection to the anode
|> "button" (and in the case where the gun assembly includes an accelerating
|> electrode at anode potential, most definitely does not provide THAT
|> connection).
Bob is indeed correct here in more than one way. A look in the old
RCA picture tube manual backs this up, as does SAMS Reference Data
handbook. The internal coating around the perimeter of the CRT
(not the aluminum or tin CRT face coating) is referred to as a
"dag" as well as the outer coating.
Thankfully, I didn't need to go to a f****** library to find it, either.
One sparkling water for Mr. Vanderbyl (no caffeine in that, is there).
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: dhembrow@eoe.co.uk (David Hembrow)
Subject: Re: SID chip to IBM system bus
Organization: EO Europe Limited, Cambridge, UK
Lines: 10
X-Newsreader: TIN [version 1.1 PL6]
Mr MC Howell (g90h6721@hippo.ru.ac.za) wrote:
: Please don't ask questions like "why don't you buy a soundblaster".  The
: answer is simple "Overpriced considering the sound quality".
Why not try one of the projects to build a DAC connected to the parallel
port as documented in some files which come with modplay ? These vary from
a 4 DAC design to a simple single DAC made only of resistors.--
David Hembrow                   EO Europe Ltd.,
email:  dhembrow@eoe.co.uk      Abberley House, Granhams Road,
Great Shelford, Cambridge CB2 5LQ, England
From: leapman@austin.ibm.com
Subject: HeathKit/Zenith
Article-I.D.: austin.C52EGz.27t3
Reply-To: $LOGIN@austin.ibm.com
Organization: IBM Austin
Lines: 3
Originator: leapman@junior.austin.ibm.com
Does anyone out there have the toll-free (catalog request and order line) for
Heathkit/Zenith?  Please post the number if you've got it!  Thanks.
From: victor@inqmind.bison.mb.ca (Victor Laking)
Subject: Re: Info on NEC 3D Multisync monitor
Organization: The Inquiring Mind BBS  1 204 488-1607
Lines: 43
myers@hpfcso.FC.HP.COM (Bob Myers) writes:
> > I am looking for any info I can get on the NEC 3D monitor.
> > I know that it is a multisync but that is about all.
> > I plan on buying one second-hand in a while depending on its specs.
> >
> > Does anyone know the min/max frequencies, whether it is interlaced,
> > non-interlaced, or both, video compatability, etc?
> > I have seen a reference to it being .28 pitch with 1024 X 720 resolution
> > and that it supports SVGA from one source and that it doesn't support
> > SVGA from another source.  (Neither source seemed to have much reliable
> > info so I don't want to take a guess.)
>
> I'm at home right now, and so am away from my monitor files; the following
> is off the top of my head, subject to revision, worth-what-ya-pay-for-it
> sort of info.  If you don't hear from anyone who has spec sheet in hand,
> e-mail me and I'll look it up.
>
> If I'm remembering correctly, the 3D is a 14" 0.28 mm pitch multisync that
> covers at least VGA (31.5 kHz horizontal, 60 Hz vertical) to 1024 x 768
> 60 Hz (which is going to be about 48 kHz horizontal).  It may go somewhat
> higher than that on the horizontal, but you won't be happy with anything
> beyond 1024 x 768 on a 14" 0.28 tube; you probably won't be too thrilled
> with the 1024 x 768 on this tube, but it *will* sync up and display it.
> (I prefer at least a 16" 0.28 for this resolution.)  Since SVGA is 800x600,
> it'll do that too.  The horizontal range probably goes lower than 31.5, but
> I don't know if it goes all the way down to straight NTSC-rate TV (which need
> about 15.75 kHz sweep).  As far as "video compatibility" (if I'm reading
> the question right: it won't take anything but analog RGB inputs.  In other
> words, it has no way to decode NTSC or Y/C video inputs.  You would need
> some sort of board to to this conversion - like the sorts of things that
> let you display NTSC on a VGA display.
>
> Hopefully, now, I'll see this response of mine, and it'll remind me to
> look this stuff up and confirm it.  (Or force me to post a hasty retraction!)
Ok, I was under the impression that it accepted digital input.
I still don't know for sure if it accepts BOTH interlaced and
non-interlaced as I have gotten conflicting info.
victor@inqmind.bison.mb.ca
The Inquiring Mind BBS, Winnipeg, Manitoba  204 488-1607
From: cobust@seagoon.ee.sun.ac.za (Cobus Theunissen)
Subject: Wide band Analog time delay
Organization: Rhodes University, Grahamstown, South Africa
X-Newsreader: TIN [version 1.1 PL8]
Lines: 6
Hi there,
I am looking for a wide band analog time delay (not phase delay)
variable from 200 microseconds to 2 milliseconds.
Please reply via email to rrc@firga.sun.ac.za
From: jmichael@vnet.IBM.COM
Subject: Re: A to D hardware for a PC
Article-I.D.: almaden.19930406.072523.946
Lines: 7
If you can find a copy of "8088 Assembler Language Programming: The IBM PC"
by Willen and Krantz, 2nd ed. pub. by Sams, there is a discussion of the
game control adapter, monostable multivibrators, and conversion to other
uses, as well as an assembler program. If you need greater accuracy, there
is no reason you couldn't modify the approach to suit your needs.
Jim
From: scst83@csc.liv.ac.uk (Mr. C.D. Smith)
Subject: Re: Homebuilt PAL (EPLD) programer?
Organization: Computer Science, Liverpool University
Lines: 27
Nntp-Posting-Host: goyt.csc.liv.ac.uk
In sci.electronics timd@fenian.dell.com writes:
>Anyone know a reasonable circuit for programming PALs?  I am interested
>in programming a wide range of EPLDs but would be happy with something
>that could handle a 22V10 or thereabouts.
I too would be interested in ANY information on the subject of programing
PALS etc.....
Better to know what your on about before you start something, I always
say. Often saves you a packet as well !!
Thanks in advance..
Chris ;-)
+====================================================================+
|Name : Mr Chris Smith       |     Twang on that 'ole guitar !       |
|Addrs: scst83@uk.ac.liv     |                                       |
|Uni  : Liverpool University |Quest: To build more and more hardware |
|Dgree: Computer Science     |                                       |
+====================================================================+
"What ever the Sun may be, it is certainly not a ball of flaming gas!"
-- D.H. Lawrence.
* All views expressed are my own, and reflect that of private thought. *
From: hanavin@huey.udel.edu (Chuck Hanavin)
Subject: Re: HeathKit/Zenith
Nntp-Posting-Host: huey.udel.edu
Organization: University of Delaware, Newark
Lines: 7
In article <C52EGz.27t3@austin.ibm.com> $LOGIN@austin.ibm.com writes:
>
>Does anyone out there have the toll-free (catalog request and order line) for
>Heathkit/Zenith?  Please post the number if you've got it!  Thanks.
----------------------------------------------------
1-800-253-0570
From: long@spk.hp.com (Jerry Long)
Subject: Re: Principle_of_the_Breathalyzer
Article-I.D.: spk.C52I89.GEq
Distribution: na
Organization: Hewlett-Packard
Lines: 31
X-Newsreader: TIN [version 1.1.4 PL6]
william burchill (williamb@ee.ubc.ca) wrote:
: 	Does anybody out there know how the hand held breathalyzer used
: by our police works?  I would like to hear about this and the more
: general problem of detecting smells by machine.
:
: Thanks, William.
:
: williamb@ee.ubc.ca
:
From what I have read about these little gadgets, it works on
a electrochemical galvanic principle. The sensing unit has a
chemical matrix which produces an electrical voltage proportional
to the amount of chemical compound it is designed for ... in this case
I believe it is the Hydroxyl group???
I have also heard -  not tested :-)  - since common gasoline is also
a member of this Hydroxyl group, it will also cause a failing breathalizer
failure! Next time you get stopped for DUI, say you just siphoned gas from
your neighbors car (you know..... the Oklahoma credit card) and chances
are you won't get a DUI ticket!!!!
Jerry Long
long@spk.hp.com
****************************************
Disclaimer.... Opinions are my own and
do NOT reflect those of my employer.
****************************************
From: kenh@sail.LABS.TEK.COM (Ken Hillen)
Subject: RF data transmission
Article-I.D.: sail.13601
Distribution: usa
Organization: Tektronix Inc., Beaverton, Or.
Lines: 10
I need a off-the-shelf method of transmitting small amounts of data up to
300 feet.  The data is low speed and can be encoded as needed.  Low power
on the transmitting end would be a plus.  An FCC certified product would
be prefered.
If you have any pointers to products or companies I'd appreciate hearing from
you.
Thanks,
Ken
From: massey@travis.llnl.gov
Subject: Re: Jacob's Ladder
Article-I.D.: travis.1993Apr6.093828.1
Organization: Lawrence Livermore National Laboratory
Lines: 15
NNTP-Posting-Host: travis.llnl.gov
In article <C4z6x7.16B@murdoch.acc.Virginia.EDU>, dgj2y@kelvin.seas.Virginia.EDU (David Glen Jacobowitz) writes:
> 	I've been wanting to build a Tesla coil for quite awhile now (
> who doesn't, right? ) and I thought it would be a good intermidiate
> step to build a JAcob's Ladder first.
> 	Well, I have been looking for a high voltage transformer that
> is reasonable inexpensive ( neon sign transformers cost mucho ).
In the past I've managed to buy used neon sign transformers from sign shops
for about $20. Try calling around.
Warren N. Massey                                      Massey@Travis.LLNL.Gov
Lawrence Livermore National Laboratory   7000 East Ave., P.O. Box 808, L-495
Livermore, Calif. 94550  <<<My opinions are mine alone>>>      (510)422-1958
From: pw@panix.com (Paul Wallich)
Subject: Re: Help with ultra-long timing
Organization: Trivializers R Us
Lines: 16
In <1pqu12$pmu@sunb.ocs.mq.edu.au> johnh@macadam.mpce.mq.edu.au (John Haddy) writes:
>In article <C513wI.G5A@athena.cs.uga.edu>, mcovingt@aisun3.ai.uga.edu (Michael Covington) writes:
>|> Instead, use a quartz crystal and divide its frequency by 2 40 times
>|> or something like that.
>... Wouldn't a crystal be affected by cold? My gut feeling is that, as a
>mechanically resonating device, extreme cold is likely to affect the
>compliance (?terminology?) of the quartz, and hence its resonant frequency.
Yes, but in a fairly reproducible way. -40 is only a smidgen of the
distance to absolute zero. And in any case you're going to have to
borrow freezer space from a bio lab or someone to test/calibrate this
darling anyway. Btw, you're probably going to want those big capacitors
you found to fire the solenoid -- High current drain on frozen batteries
can be an ugly thing.
paul
From: moffatt@bnr.ca (John Thomson)
Subject: Re: What is Zero dB????
Nntp-Posting-Host: bcarhdd
Organization: Bell-Northern Research, Ottawa, Canada
X-Newsreader: TIN [version 1.1 PL6]
Lines: 47
Joseph Chiu (josephc@cco.caltech.edu) wrote:
: sehari@iastate.edu (Babak Sehari) writes:
:
: >Similarly, people usually use dB for dBm. Another common mistake is spelling
: >``db'' instead of ``dB'' as you did in your article. See the ``B'' is for
: >``Bell'' company, the mother of AT&T and should be capitalized.
:
: Thus, a deciBell (deci-, l., tenth of + Bell) is a fractional part of the
: original Bell.  For example, SouthWestern Bell is a deciBell.
Out of what hat did you pull this one?  dB is a ratio not an RBOC!
: And the measure of current, Amp, is actually named after both the AMP company
: and the Amphenol company.  Both companies revolutionized electronics by
: simulatenously realizing that the performance of connectors and sockets
: were affected by the amount of current running through the wires.
Sorry.  The unit for current is the AMPERE which is the name of a french-man
named AMPERE who studied electrical current.  The term AMP is just an abbreviation
of it.  The company AMP came after the AMPERE unit was already in use.
: The Ohmite company was the first to characterize resistances by numbers, thus
: our use of the Ohms...
I don't know about this one, but it doesn't sound right.
:
: Alexander Graham Bell, actually, is where Bell came from...
Well you got one thing right!
:
:
:
: Actually, Bel refers
:
: >                          With highest regards,
: >                               Babak   Sehari.
:
: >--
: --
: Joseph Chiu        | josephc@cco.caltech.edu  "OS/2: You gotta get this thing!"
: MSC 380 - Caltech  |
: Pasadena, CA 91126 |   OS/2: The operating system of tomorrow, today.
: +1 818 449 5457    |
Greg Moffatt
Bell-Northern Research Inc., Ottawa Canada
"My opinions; not BNR's"
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: Re: Police radar....Just how does it work??
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 35
In article <1993Apr2.182216.28603@walter.bellcore.com>, deaddio@ski.bellcore.com (Michael DeAddio) writes:
|> |> Question 2:
|> |>
|> |> 	If I am right about the doppler(if I spell it different every time,
|> |> maybe one will be right) effect, how does the radar get an accurate reading
|> |> when the car containing it is moving??  It would seem to me ( for all thats
|> |> worth) that it would need to be calibrated with the speedometer of the car
|> |> containing it??  I am fairly sure this isn't the case, so whats the deal??
|>
|> Essentially, this is actually how it is done.  The radar gun is tied into
|> the speedometer of the car.
No, it is independent of the speedometer. The gun processes two doppler
returns--the speed of the car relative to the pavement and the speed
of the target, taking the difference between the two. Some guns with
a "moving mode" actually have a split beam with one beam aimed
preferentially at the pavement.
Car and Driver had a good article on traffic radar, but it was back in
1985. I used its contents and references to defend myself against a bogus
radar-measured ticket. It detailed "moving mode," which is easier to
defend against because of the increased amount of variables.
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: scst83@csc.liv.ac.uk (Chris Smith)
Subject: Re: books/info on audio DSP ??
Distribution: rec,sci
Organization: Computer Science, Liverpool University
Lines: 28
Nntp-Posting-Host: goyt.csc.liv.ac.uk
In sci.electronics,rec.audio David S. Rowell writes:
>I assume these are appropriate newsgroups for this question.  I am looking
>for a good book, articles, anything on audio DSP.  Theory is nice, but
>I'm really looking for something very much on the applications side.
>I want to look into it as my new hobby, so I need all the direction
>I can get.  Any comments would be welcome, too.
I'm looking to build a DSP for guitar processing. Hence lots of background
information would be really useful !
If anyone's got any info, could they email.....
Thanks in advance...
Chris ;-)
+====================================================================+
|Name : Mr Chris Smith       |     Twang on that 'ole guitar !       |
|Addrs: scst83@uk.ac.liv.csc |                                       |
|Uni  : Liverpool University |Quest: To build more and more hardware |
|Dgree: Computer Science     |                                       |
+====================================================================+
"What ever the sun may be, it is certainly not a ball of flaming gas!"
-- D.H. Lawrence.
* All views expressed are my own, and reflect that of private thought. *
From: gerald.belton@ozonehole.com (Gerald Belton)
Subject: PC games (joystick) port
Article-I.D.: ozonehol.5109.442.uupcb
Reply-To: gerald.belton@ozonehole.com (Gerald Belton)
Distribution: world
Organization: Ozone Online Operations, Inc., DBA The Ozone Hole BBS
Lines: 29
>Subject says it all - could someone tell me the pinout
>for a PC type analogue joystick port?
Joystick A:
1        +5 VDC
2        Button 1
3        X Axis
4        Ground
5        Ground
6        Y Axis
7        Button 2
8        + 5 VDC
Joystick B:
9        +5 VDC
10        Button 1
11        X Axis
12        Ground
13        Y axis
14        Button 2
15        +5 VDC
---
. SLMR 2.1 . Soft judges make hardened criminals.
----
The Ozone Hole BBS * A Private Bulletin Board Service * (504)891-3142
3 Full Service Nodes * USRobotics 16.8K bps * 10 Gigs * 100,000 Files
SKYDIVE New Orleans! * RIME Network Mail HUB * 500+ Usenet Newsgroups
Please route all questions or inquiries to:  postmaster@ozonehole.com
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: Re: Police radar....Just how does it work??
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 25
In article <1993Apr2.182402.28700@walter.bellcore.com>, deaddio@ski.bellcore.com (Michael DeAddio) writes:
|> |> The 'beam' is split in two, with one beam aimed at the target car (sort of) and
|> |> the other at the ground.  The speeds of each are calulated for the final
|> |> number
|>
|> Actually, this is true on the more expensive ones, but the cheaper ones
|> just read the speedometer.
I've never seen a speedometer-reading model. Are you sure? Who makes
them? Consider the difficulty of reading the speedo on various makes
of cars in use... I've seen single beam moving-mode and split beam
moving-mode.
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: Re: HV diodes
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 25
In article <1993Apr2.204617.14179@mprgate.mpr.ca>, vanderby@mprgate.mpr.ca (David Vanderbyl) writes:
|> dtmedin@catbyte.b30.ingr.com (Dave Medin) writes:
|> >The CRT, in fact, does have an intentional built-in capacitor for
|> >its function just as IC's have built-in transistors, etc.
|>
|> Gee, Mr. Myers, are we going to let this go without a CORRECTION?
Two things:
1. Read your own posts. I was agreeing with Bob. No correction
needed.
2. Don't quote stuff out of context.
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: jsc52962@uxa.cso.uiuc.edu (Jeffrey S. Curtis)
Subject: Re: What is Zero dB????
Organization: University of Illinois at Urbana
Lines: 19
moffatt@bnr.ca (John Thomson) writes:
}Out of what hat did you pull this one?  dB is a ratio not an RBOC!
} [...]
}Sorry.  The unit for current is the AMPERE which is the name of a french-man
}named AMPERE who studied electrical current.  The term AMP is just an abbreviation
}of it.  The company AMP came after the AMPERE unit was already in use.
} [...]
}I don't know about this one, but it doesn't sound right.
} [...]
}Well you got one thing right!
Hello? John? Oh, nevermind...
Jeff
--
Jeffrey S. Curtis sidewinder@uiuc.edu | "Resplendent in full regalia, they
The Power of 37  free2207 at uiucvmd | revel in their role as self-appointed
Sony - Phase Linear - Sanyo - Sennet | critics of the establishment..."
Jensen - Polk - StreetWires - Proton |   -- INXS _Welcome to Wherever You Are_
From: caryd@a.cs.okstate.edu (CARY DAVID ALLEN)
Subject:  Self-modifying hardware
Organization: Oklahoma State University, Computer Science, Stillwater
Lines: 70
Permit me to quote fragments of
praetzel@sunee.uwaterloo.ca's article
out of context.
-Newsgroups: sci.electronics,comp.lsi.cad
-From: praetzel@sunee.uwaterloo.ca (Eric Praetzel)
-Date: 10 Feb 93 15:46:41 GMT
-  Currently the XNF format is propierty and I know of at least on person at
-a university who was able to get it after signing a non-disclosure agreement.
-The Xilinx-bit map format is pretty well top secret.  I would love to know it
-because then you could make self_modifying_hardware  ;-)  As it is I had to
-reverse eng. the Xilinx tools to dump the bit map to the FPGA because it only
-runs on the computer with the hardware key.
self-modifying hardware could be *very* interesting --
computers that could write thier own programs (assemblers, compilers)
were an immense breakthrough from calculators that couldn't.
-  I eagerly await a programmable gate array which uses a PD format and does
-not cost your first born to program.  Till then we will keep on reverse
-engineering whatever we can.  As it is one company that I worked at has gone
-under.  FPGAs are what they needed to make their product competitive.  They
-could not afford them.  In the end you could say that they could not afford
-to not use them but the management discovered that too late.
-   - Eric
my condolences.
i can't even imagine what i could do with self-modifing hardware.
i *can* imagine self-modifying software,
and even though *all* my teachers say that's BAD, even Worse than GOTO,
check out what the experts *used* to say about self-modifying code:
(he uses "orders" rather than "opcodes")
"On the Principles of Large Scale Computing Machines"
by Goldstine and von Neumann,
collected in
_John von Neumann: Collected Works, Vol. V_
reprinted here with absolutely no permission from anyone.
"We plan... to have a full size (40 binary digit) word hold
either contain
1 full size number (... equivalent to 12 decimal digits,
but we will use the first binary digit to denote the sign)
or two (20 binary digit) orders.
....
It should be added that this technique of
automatic substitutions into orders,
i.e. the machine's ability to modify its own orders
(under the control of other ones among its orders)
is absolutely necessary for a flexible code. Thus, if
part of the memory is used as a "function table", then
"looking up" a value of that function for a value of the
variable which is obtained in the course of the computation
requires that the machine itself should modify, or
rather make up, the reference to the memory in the order which
controls this "looking up", and the machine can only make this
modification after it has already calculated the value of the
variable in question.
On the other hand, this ability of the machine to modify its
own orders is one of the things which makes coding
the non-trivial operation which we have to view it as."
david cary, tenor, e- and comp. engineering (finger caryd@a.cs.okstate.edu).
227 S. 163 E. Ave, Tulsa, OK  74108-3310, USA, Sol 3, Universe v. 1.2
--
david cary, tenor, e- and comp. engineering (finger caryd@a.cs.okstate.edu).
227 S. 163 E. Ave, Tulsa, OK  74108-3310, USA, Sol 3, Universe v. 1.2
From: rsd@sei.cmu.edu (Richard S D'Ippolito)
Subject: Re: What is Zero dB????
Organization: The Software Engineering Institute
Lines: 10
In article <1pkveuINNduk@gap.caltech.edu>, Joseph Chiu writes:
> The Ohmite company was the first to characterize resistances by numbers, thus
> our use of the Ohms...
Yeah, right.  And the company was started by George Simon Ohmite.
Rich
From: jgd@dixie.com (John De Armond)
Subject: Re: Help with ultra-long timing
Article-I.D.: dixie.8#_v!0a
Organization: Dixie Communications Public Access.  The Mouth of the South.
Lines: 44
wellison@kuhub.cc.ukans.edu writes:
>I have a project that was drooped in my lap that is somewhat a pain to design.
>What I am looking for is a stable ultra-long solid state timer. What they want
>to do is to place this thing on the Antartic ice shelf and measure the amount
>of snow fall over a period of six weeks. Every two weeks, they want to trip a
>selonoid to discharge different colored pellets by gas pressure out across the
>snow. Then by digging down into the snow, the snow fall amount can be measured
>as they come to the different color pellets.
>The problem is trying to build a timer that would stand the cold (-40 degrees)
>and a power source that wouldn't drain. I have looked at the XR-2204 timers and
>the standard NE556 dual timers, but thier temp specs won't go that low. Also,
>two weeks equates to 1,209,600 seconds per firing, which means one big timing
>cap ! I have found 2.2 farad (yes, Farad !) caps that have a working voltage of
>5 volts and are small in size.
Why are you fooling around with analog for this job?  A single chip
micro and a crystal will do the job reliably and easily.  An 8748 only
costs about $5.  That and a $1 crystal and you're in business.  Embed
the whole thing in a foam insulated blanket, power it from a solar cell,
use the excess power to heat the assembly during the day and rely
on the insulation to hold the heat during darkness.  If you don't want
to try thermal management, contact someone like ICL and have them cut
you a special low temperature crystal.  It'll cost at most $20.
If you use a single chip micro, you're looking at a parts count of
maybe 7.  A processor, a crystal, two caps on the crystal, a power FET
to fire the solenoid a flyback diode and a battery.  This is fewer parts than
you can build an analog timer for and is infinitely more reliable.  Add
a power zener diode (for heat) and a solar cell and the parts count
screams up to 9.
PD assemblers are available for all the common single chip micros.  This
application is so trivial you could even look up the op codes in the
programmer's guide and create the binary with a hex editor.
John
--
John De Armond, WD4OQC               |Interested in high performance mobility?
Performance Engineering Magazine(TM) | Interested in high tech and computers?
Marietta, Ga                         | Send ur snail-mail address to
jgd@dixie.com                        | perform@dixie.com for a free sample mag
Need Usenet public Access in Atlanta?  Write Me for info on Dixie.com.
From: jmichael@vnet.IBM.COM
Subject: Radar Detector DETECTORS?
Article-I.D.: almaden.19930406.131941.134
Lines: 3
They detect the oscillator operating in the detector. Saw a story about
their use in Canada. Now don't go putting oscillators in your cars... :-)
From: scst83@csc.liv.ac.uk (Mr. C.D. Smith)
Subject: Voltage Multiplier Problem.
Organization: Computer Science, Liverpool University
Lines: 53
Nntp-Posting-Host: goyt.csc.liv.ac.uk
Hi,
I've just built a valve preamp and use a diode/capacitor
voltage multiplier to step the 12vAC supply voltage up to approx
260vDV. As the load resistance increases, the RC constant decreases
and hence the output voltage drops. I need as high an output
voltage as possible. (about 260v).
The circuit consists of seven voltage multiplier stages
(ie 14 diodes and 14 capacitors) each capacitor develops about 38v
across them, and I take the output from across seven capacitors=260v.
Each capacitor is 100mfd at 68v.
If I increase each of the capacitors rating (220-470mfd), that will
increase the RC constant, and hence alleviate some of the problem.
These capacitors are going to be a little expensive as I need 14 of
them, So:
1. What would happen if I connected a 470mfd at 400v capacitor in parallel
with the output (and hence in parallel with the seven 100mfd capacitors)?
Will it, as I assume, increase the C in circuit and hence increase
the RC time constant? If it does, and my output voltage becomes more
stable by doing this, then I will have killed two birds with one stone...
as I am experiencing some 50Hz ripple (and hence amp hum), and this new
capacitor will 'smooth' this out.
and
2. Can anyone recomend a suitable value for an inductor (choke) to
be placed in the output line of the power supply to filter out
the 50Hz mains hum. Lowest resistance possible !
I've not got my preamp with me at the moment because it is TOO MUCH
of a distraction.... (I'm at university and I've got to get my
dissertation finished in two weeks !!!!!!!) hence I'm mailing not
playing with my solderoing iron (it'll be cheaper too in the long
run... especially if 14 new large capacitors don't work as planned!)
Email please.... Can't always read the net.....
Thanks in advance..
Chris ;-)
+====================================================================+
|Name : Mr Chris Smith       |     Twang on that 'ole guitar !       |
|Addrs: scst83@uk.ac.liv.csc |                                       |
|Uni  : Liverpool University |Quest: To build more and more hardware |
|Dgree: Computer Science     |                                       |
+====================================================================+
"What ever the sun may be, it is certainly not a ball of flaming gas!"
-- D.H. Lawrence.
* All views expressed are my own, and reflect that of private thought. *
From: koops@gaul.csd.uwo.ca (Luke Koops)
Subject: Speaker design software?
Organization: Computer Science Dept., Univ. of Western Ontario, London, Canada
Summary: Searching for speaker deisn software/shareware/freeware
Keywords: speaker, design, software
Nntp-Posting-Host: obelix.gaul.csd.uwo.ca
Lines: 13
Hi.  I'm looking for software to aid a friend of mine with designing speakers.
Does this type of software exist?  If anyone can point me toward a shareware or
freeware product with this description, that would be ideal.
...Steve van der Burg (using a friend's account)
(p.s. Excuse the terseness of the message;  I'm having difficulty stringing
readable sentences together today, for some reason.)
--
-Luke Koops
From: jmichael@vnet.IBM.COM
Subject: Electric power line "balls"
Article-I.D.: almaden.19930406.142616.248
Lines: 4
Power lines and airplanes don't mix. In areas where lines are strung very
high, or where a lot of crop dusting takes place, or where there is danger
of airplanes flying into the lines, they place these plastic balls on the
lines so they are easier to spot.
From: behnke@FNALF.FNAL.GOV (M.L. 'Broomen' Behnke)
Subject: Re: Electric power line "balls"
Article-I.D.: fnnews.1psrgl$6cb
Reply-To: behnke@FNALF.FNAL.GOV
Distribution: usa
Organization: Fermi National Accelerator Lab
Lines: 27
NNTP-Posting-Host: fnalf.fnal.gov
In article <1993Apr6.203237.20841@eagle.lerc.nasa.gov>, fsset@bach.lerc.nasa.gov (Scott Townsend) writes:
>I got a question from my dad which I really can't answer and I'd appreciate
>some net.wisdom.
>
>His question is about some 18-24" diameter balls which are attached to
>electric power lines in his area.  He's seen up to a half dozen between
>two poles.  Neither of us have any experience with electric power distribution.
>My only guess was that they may be a capacitive device to equalize the
>inductance of the grid, but why so many between two poles?.
>
>Anyone know what they really are?  Is there a related FAQ for this?
>Is there a better group to submit to?
>
>We'd both appreciate some enlightenment.
>
The balls are used to reduce the amplitude of oscillations of the wire during
periods of high winds.  I've seen what looks like paint cans filled with
concrete used for the same purpose.
Mike Behnke             | Senior Tech/Advisor | Quid est illuidin aqua??
Fermi Nat Accel Lab     | Equipment Suuport   |
Batavia, Il.            | Computing Div       | PISTRIX!!  PISTRIX!!
BEHNKE@FNALF.FNAL.GOV   |                     |
My opinions are my own, not of the lab. So, if you don't like them, call
1-800-UWH-INER
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: Re: Oscilloscope triggering
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 55
In article <C4vs0G.5ux@murdoch.acc.Virginia.EDU>, dgj2y@kelvin.seas.Virginia.EDU (David Glen Jacobowitz) writes:
|> >>Can someone out there explain exactly what the 'trigger'
|> >>feature found on oscilloscopes does?
|> >
|> 	{ lots og good explanation deleted}
<lots more deleted>
|> 	Is it just me, or does anybody else out there NOT like digital
|> scopes. My school has some beauutful 100Mhz HP that are digital with
|> all the bells and whistles, including soft-keys, which I think are a
|> loveley touch. ( that is, software keys. ) You don't forget that you
|> are dealing with a computer. Those scopes even with all their
|> neatness, still make the ickyest looking waves. Lotsa features, but
|> ugly output. And those are the best digitals I have ever seen. I've
|> seen a lot of cheaper digitals and they look terrible.
I think the hangup with digital scopes is that you have to know so much
more about them and how they work on a scope-by-scope basis, and
some of the functions are typically presented, in my opinion,
in a counter-intuitive fashion (HP has made some strides in their
54600 series, IMO). Automatic setups are fine for simple,
repetitive waveforms, but can give you some crazy results on more
complex events where you need to understand how the scope is
actually measuring/processing the event. For example, is the scope
in "equivalent time" or in "real time" sampling mode (equivalent time
being a mode where samples are built-up slowly by adding a delay to
the trigger event each sweep)? What was the scope's actual sampling
rate at the time? How is the data being massaged after capture but
before display, etc. One common misconception is the speed of the scope.
Is the HP scope you're using really a 100 MHz scope? Or is it a 20 MHz
sample rate scope (~5 MHz single shot significance) whose front
end including S/H can support 100 MHz waveforms (important for
equivalent time sampling)? The 100 MHz input in this case really
only helps you when your waveform is repetitive, or on a single
sample, when you get lucky and hit a transient event during a sample time.
So, there are a lot more variables in understanding how to get
useful information from a digital scope. I prefer an analog scope for
general use and the digital for events where I need storage for
later analysis or comparison, when the event is within the capability
of the scope. Now, for the price of true 100 MHz digital scopes to
fall...
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: heinboke@tnt.uni-hannover.de (Andreas Heinbokel)
Subject: LOOKING for AD PC-Board
Reply-To: heinboke@tnt.uni-hannover.de
Organization: Universitaet Hannover, Theoretische Nachrichtentechnik
Lines: 41
This is for a friend of mine. Please send answers directly to him (E-Mail
adress see below )!
HIGHSPEED  ANALOG-DIGITAL PC-BOARD
Hello LAdies and Gentleman !
I am looking for a highspeed A/D PC-Board with a sampling rate above 250 MHz an a
resolution of 8-bit. The sampling rate can be arranged by an interleave mode where
the time equivalent sampling yields 2, 4 or 8 times higher sampling rate than
the A/D-Converter uses in non interleave mode.
The board must content an A/D-Converter similar to Analog Devices AD 9028 or
AD 9038 or if available a faster on.
If you a PC-Board (16-bit slot, ISA) with this specification or better, please
send me an EMail
hansch@cdc2.ikph.uni-hannover.dbp.de
or a Telefax to: ++49 / 511 / 7629353
Thanks in advance for your help !
Sincerely
Matthias Hansch
IKPH, University of Hannover, Germany
---
Andreas Heinbokel
heinboke@tnt.uni-hannover.de
*** ... all wisdom is print on t-shirts ***
From: gmc@cthulhu.semi.harris.com
Subject: Re: What is Zero dB????
Nntp-Posting-Host: cthulhu.mlb.semi.harris.com
Organization: Analog
Lines: 57
In article <1993Apr6.132429.16154@bnr.ca>
moffatt@bnr.ca (John Thomson) writes:
>Joseph Chiu (josephc@cco.caltech.edu) wrote:
>
>: Thus, a deciBell (deci-, l., tenth of + Bell) is a fractional part of the
>: original Bell.  For example, SouthWestern Bell is a deciBell.
>
>Out of what hat did you pull this one?  dB is a ratio not an RBOC!
>
>: And the measure of current, Amp, is actually named after both the AMP company
>: and the Amphenol company.  Both companies revolutionized electronics by
>: simulatenously realizing that the performance of connectors and sockets
>: were affected by the amount of current running through the wires.
>
>Sorry.  The unit for current is the AMPERE which is the name of a french-man
>named AMPERE who studied electrical current.  The term AMP is just an abbreviation
>of it.  The company AMP came after the AMPERE unit was already in use.
>
>: The Ohmite company was the first to characterize resistances by numbers,
>: thus our use of the Ohms...
>
>I don't know about this one, but it doesn't sound right.
>
>:
>: Alexander Graham Bell, actually, is where Bell came from...
>Well you got one thing right!
>:
Actually, I think J. Chiu knows the score and is just being
silly. However, "decibel" is in fact 1/10th of a bel. He is
right on that one, but I don't know if it was accidental or not.
Strictly defined, a bel is the ratio of the log of two power levels,
and a decibel is 1/10th of a bel so you have 10X decibels for every bel,
hence bel=log(P2/P1) and decibel=10Xlog(P2/P1).
The bel, ohm, volt, farad, ampere, watt, hertz, henry, etc. are
all named for pioneers in the field. It's a traditional and fine
way to honor researchers who discover new knowledge in a new field.
Hertz was one of the most important of the early electronics explorers,
but had been left out in having a term or unit named after him
until recently, (1960's, prior to that what is now a hertz was a cps.)
All the other units were defined many decades earlier.
--
----------------------------------------------------------------------
----------------------------------------------------------------------
From: cab@col.hp.com (Chris Best)
Subject: Re: Police radar....Just how does it work??
Organization: your service
Lines: 7
NNTP-Posting-Host: hpctdkz.col.hp.com
I've seen several references to split- or separate-beam radars, which I
claimed didn't exist.  Gotta eat some crow here - I wasn't aware of them.
All I really knew was that it can be done with one beam.
I believe the rest of what I said is accurate, though.
Mmmmmmm....crow.... (oops-wrong group)
From: ragee@vdoe386.vak12ed.edu (Randy Agee)
Subject: Radar detector DETECTORS?
Organization: Virginia's Public Education Network (Richmond)
Lines: 50
Here's one I hope some knowledgeable readers will make a comment or
contribution to:
In the State of Virginia radar detectors are illegal, period.  If
you are caught with one it will be confiscated on the spot and will
not be returned until after you appear in court and pay your fine.
The fine for having a radar detector accessible in a motor vehicle
(even if it is not on) is $250.00.  Sorry, tourist, ignorance of
the law is no excuse - they will get you too!
It used to be that the only way the law could be enforced was for
an officer to actually see the radar detector.  Not any more!  Many
law enforcement agencies are now using radar detector detectors.
Right, a super sensitive receiver that is capable of picking up RF
from the radar detector itself.  My first reaction was "no way!"
But, guess again, these little buggers really work and the police
are writing citations right and left for people using radar
detectors.  One news story quoted an officer as saying that he had
found the radar detector in all of the cars he stopped except one,
and he could never figure out where it was - but he knew it was
there.  This tends to make one assume there are few false arrest.
Now, before I get flamed, please understand that I do drive at or
near the speed limit.  I do not need a radar detector to keep me
from getting a speeding ticket.  But, I do like to know when my
speed is being clocked or a speed trap is functioning.  My radar
detector now stays locked in my trunk when I am in Virginia (which
is what they want - and yes, what the law says, and I intend to
obey the law!) and is only used in states where it is legal.
For my fellow hams, I am not a microwave person - my mind only
works in the HF spectrum between 10 and 80 meters.  Microwave
enlightment may be necessary.
So, the questions are -
What do the radar detector detectors actually detect?
Would additional shielding/grounding/bypassing shield stray RF generated by
a radar detector, or is the RF actually being emitted by the detector
antenna?
Are any brands "quieter" than others?
==============================================================================
Randy T. Agee - ARS WB4BZX       | At some point, you probably pondered The
P.O. Box 2120 - 20th floor       | Meaning of Life, and you came up with a
Virginia Department of Education | satisfactory answer, which has or has not
Richmond, VA 23216-2120          | stood the test of time, or you shrugged
Phone (804) 225-2669             | mightily, muttered "Beats the heck out of
ragee@vdoe386.vak12ed.edu        | me," and ordered a cheeseburger.
=============================================================================
From: scst83@csc.liv.ac.uk (Mr. C.D. Smith)
Subject: Re: Why is telephone audio 300-3000 Hz?
Organization: Computer Science, Liverpool University
Lines: 47
Nntp-Posting-Host: goyt.csc.liv.ac.uk
>> telephone systems have the capability of a passband of 30hz to 4Khz.
>> The reason they do not implement this is: It is not backward compatable
>> to every telephone system.  In addition, the most effecent mix of
>> electrical effecency, and intelegability closly mateches a 300hz-3khz
>> passband.
>
>Close, but no banana (to paraphrase Garfield)...
>The reason 300-3300 Hz is used is that voice channels used to occupy
>4kHz bands when multiplexed on a trunk line. Therefore, 300Hz at the
>bottom, and 700Hz at the top of this band were filtered to minimise
>interference with the next band.
>
>Nowadays, digital trunks have made this less relevant, but the phone
>companies still see no reason to improve quality (especially for free!).
>Therefore, digital "chunk of a trunk" segments still have a guaranteed
>bandwidth of only 4kHz (so they can carry the equivalent of one analog
>line) at the clock rate of a standard PCM T1 or E1 digital trunk.
>
>It's all historical...
Here in the UK, the bandwidth restriction apparently only apply to
local lines.. ie those used by the average domestic client. Private
lines which are run from the local exchange to the leasing client are
usually capable of a higher bandwidth if the exchange is digital.
Don't quote me on that..... But I think I remember a BT engineer
saying something to that effect when I was doing some work
shadowing a few years ago.
Byeeeee !
Chris ;-)
+====================================================================+
|Name : Mr Chris Smith       |     Twang on that 'ole guitar !       |
|Addrs: scst83@uk.ac.liv.csc |                                       |
|Uni  : Liverpool University |Quest: To build more and more hardware |
|Dgree: Computer Science     |                                       |
+====================================================================+
"What ever the sun may be, it is certainly not a ball of flaming gas!"
-- D.H. Lawrence.
* All views expressed are my own, and reflect that of private thought. *
From: rivero@sol.cie.unizar.es
Subject: Video IO ideas?
Organization: Free University of Berlin, Germany
Lines: 7
Have anyone some idea about how to build a cheap, low
resolution (or high :-) video projector...
(example: a LCD and an slide projector)
.
From: linnig@m2000.dseg.ti.com (Mike Linnig)
Subject: Re: books/info on audio DSP ??
In-Reply-To: scst83@csc.liv.ac.uk's message of 6 Apr 93 13:36:13 GMT
Nntp-Posting-Host: m2000.dseg.ti.com
Organization: Texas Instruments, Defense, Systems and Electronics Group.
<C52DsD.7pB@compsci.liverpool.ac.uk>
Distribution: rec,sci
Lines: 25
In article <C52DsD.7pB@compsci.liverpool.ac.uk> scst83@csc.liv.ac.uk (Chris Smith) writes:
> I'm looking to build a DSP for guitar processing. Hence lots of background
> information would be really useful !
>
> If anyone's got any info, could they email.....
Well, I'm not sure I'd use this to process a guitar but there was a audio
filter DSP construction article in the Sept 92 issue of QST magazine (Ham Radio
oriented).  The DSP is available in kit form for about $120.
This particular DSP filter was targetted toward processing audio to remove
noise (static).  I built it and it really works well.  The source code is
available too.  It makes a noisy audio signal much easier to hear.  Note that
this is for communication applications and is not "high fidelity".
--
- - - - - - - - - - - - - - - - - - + - - - - - - - - - - - - - - - - - +
Mike Linnig, Texas Instruments Inc. | 97.43% of all statistics are made |
Phone: (214) 575-3597  CALL: N5QAW  | up; most of them (83.6 percent)   |
Internet: mike.linnig@dseg.ti.com   | are wrong.                        |
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
From: mpaul@unl.edu (marxhausen paul)
Subject: How to kill AC inductive load spiking?
Organization: University of Nebraska--Lincoln
Lines: 20
Distribution: world
NNTP-Posting-Host: unlinfo.unl.edu
Is there a fast 'n dirty way to kill the line spiking that occurs when
an inductive load is turned on sometime other than at zero-crossing of
the AC cycle?  A capacitor kludged in somehow, etc?
I've got a microcontroller that is running a bunch of valves and pumps
in a big instrument washer, and almost everything is being switched with
zero-crossing solid state relays, so that stuff stays "quiet", AC-wise.
But there's one steam valve that gets turned on by a mechanical relay
in the water tank fill/thermostat system, and it's not under control
of my SSRs, and it does sometimes generate/radiate a spike that resets
one of my peripheral chips.  My software times out and tries again, but
I'd love to just tack in a magic spike-killing fix that would avoid having
to do some major rewiring/redesign.  A varistor would help but might not
be sufficient.  Ideas?
--
paul marxhausen .... ....... ............. ............ ............ ..........
.. . .  . . . university of nebraska - lincoln .  . . .. . .  .. . . . . . . .
.     .    .  .   .     .   .  .    .   .  .   .    .   .  grace .   .    .  .
.         .       .      .        .        .      .        .   happens .
From: vanderby@mprgate.mpr.ca (David Vanderbyl)
Subject: Re: Police radar....Just how does it work??
Nntp-Posting-Host: chip
Reply-To: vanderby@mprgate.mpr.ca (David Vanderbyl)
Organization: MPR Teltech Ltd.
Lines: 22
In article <1993Apr6.161107.2235@b30news.b30.ingr.com>, dtmedin@catbyte.b30.ingr.com (Dave Medin) writes:
|> In article <1993Apr2.182402.28700@walter.bellcore.com>, deaddio@ski.bellcore.com (Michael DeAddio) writes:
|>
|> |> |> The 'beam' is split in two, with one beam aimed at the target car (sort of) and
|> |> |> the other at the ground.  The speeds of each are calulated for the final
|> |> |> number
|> |>
|> |> Actually, this is true on the more expensive ones, but the cheaper ones
|> |> just read the speedometer.
|>
|> I've never seen a speedometer-reading model. Are you sure? Who makes
|> them? Consider the difficulty of reading the speedo on various makes
|> of cars in use... I've seen single beam moving-mode and split beam
|> moving-mode.
Obviously the police officer reads the speedometer.
I cannot believe the nit-picking in this group.
There's 2 beams, there is not, is too, etc....
|> --------------------------------------------------------------------
|> [Dave Medin's 10 line sig deleted]
From: nhowland@matt.ksu.ksu.edu (Neal Patrick Howland)
Subject: Re: Radar detector DETECTORS?
Organization: Kansas State University
Lines: 23
NNTP-Posting-Host: matt.ksu.ksu.edu
ragee@vdoe386.vak12ed.edu (Randy Agee) writes:
>It used to be that the only way the law could be enforced was for
>an officer to actually see the radar detector.  Not any more!  Many
>law enforcement agencies are now using radar detector detectors.
>Right, a super sensitive receiver that is capable of picking up RF
>from the radar detector itself.  My first reaction was "no way!"
>But, guess again, these little buggers really work and the police
>are writing citations right and left for people using radar
>detectors.  One news story quoted an officer as saying that he had
>found the radar detector in all of the cars he stopped except one,
>and he could never figure out where it was - but he knew it was
>there.  This tends to make one assume there are few false arrest.
From what I understand about radar dectectors all they are is a passive
device much like the radio in your car.  They work as an antenna picking
up that radar signals that the radar gun sends out.  Therefore there would
be no way of detecting a radar detector any more than there would be of
detecting whether some one had a radio in their car.
Neal Howland
nhowland@matt.ksu.ksu.edu
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: Re: Where do U look??
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 43
In article <1993Apr2.170955.1749@cmkrnl.com>, jeh@cmkrnl.com writes:
|> I might add that collecting last year's data books (or even ones two years out
|> of date) is usually pretty cheap, and has benefits besides:  You usually DON'T
|> want to base a design on a brand-new chip.  There may be bugs; availability may
|> be limited; the data sheets may be missing critical information that will show
|> up in the ap notes in next year's data books.  Kinda like buying Version 1.0 of
|> a major new software package:  Sometimes you get lucky, but don't count on it.
There are two more reasons to save old databooks and then beyond two
years--obsoleted parts and better application notes and tutorials.
When a part is dropped from future production planning, such as the
National MM-series white noise generators, camera sync generators, etc.,
it will disappear from current databooks although it still may be produced
for a short time (or be available from stock somewhere). Now, if you
have some old plans calling for such a device, or you have a dead
gadget on your workbench and it has such a part in it, you'll know
the functions so you can troubleshoot and substitute as necessary.
The old GE thyristor data books contain real good tutorials on
SCR and triac applications that are not found elsewhere, for
example.
|> > In summary, read. READ! ****READ!!!**** That's how you'll know what to
|> > design in, which parts to use, and how to solve the intractable problem
|> > that your boss has presented you with.
|>
|> It helps to have a prodigous memory for details...
Here, here!...
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: keith@radio.nl.nuwc.navy.mil
Subject: Tektronix 453 scope for sale
Article-I.D.: radio.623
Lines: 19
X-Received: by usenet.pa.dec.com; id AA26719; Tue, 6 Apr 93 14:52:02 -0700
X-Received: by inet-gw-1.pa.dec.com; id AA16140; Tue, 6 Apr 93 14:51:56 -0700
X-To: sci.electronics.usenet
Tektronix 453 scope for sale:
- 50MHz bandwidth
- portable (NOT one of the 5xx series boatanchors! :^)
- delayed sweep
- works fine
- I don't have the manual (they are available from various places)
- no probes
- $275 + shipping
Email me for more info...
Regards,
Keith
----
Keith Kanoun, WA2Q
kdk@radio.nl.nuwc.navy.mil
From: corleyg@ul.ie
Subject: Microstrip help wanted
Organization: University of Limerick, Ireland
Lines: 8
I need information on microstrip circuit design especially
filter design for the 1-3GHz range. Can you recommend any
good books, journals, or microstrip circuit design software.
.
all help appreciated
Gerry Corley, ECE Department, Univesity of Limerick, Ireland.
From: dpalmer@mcnc.org (W. Dev Palmer)
Subject: Re: Wanted: A to D hardware for a PC
Article-I.D.: mcnc.1993Apr6.220327.4042
Organization: MCNC Center for Microelectronics, RTP, NC
Lines: 34
In article <1993Apr6.053736.23113@doug.cae.wisc.edu> kolstad@cae.wisc.edu (Joel Kolstad) writes:
>>In <3889@ncr-mpd.FtCollinsCO.NCR.COM> Brad Wright writes:
>>
>>>	If you know much about PC's (IBM comp) you might try the joystick
>>>port.  Though I haven't tried this myself, I've been told that the port
>
>I believe that the "A-D converters" found on a joystick port are really
>timers that tick off how long it takes an R-C circuit (the R being your
>paddle) to charge up to something like 1/2 Vcc.  For games this works
>pretty well, but you certainly wouldn't want to try to take lab
>measurements off something as non-linear as that.
The best info I have seen so far is the article "Joystick Metrics:
Measuring physical properties through the PC's joystick port" by
Michael Covington in the May 1985 issue of PC Tech Journal.  It talks
about how to read all kinds of things (voltage, current, resistance) in
BASIC, and even includes code for a simple "oscilloscope" display.
It's possible to read the joystick port directly if you don't want to
use BASIC.  The detailed information for this is in the PC Technical
Reference under Options and Adapters.  You have to provide some
millisecond resolution timing functions, but that's a subject which has
appeared many times in articles from Dr. Dobb's, Circuit Cellar Ink,
etc.  Look for the public domain ztimer package on wuarchive.
Good Luck,
Dev Palmer
dpalmer@mcnc.org
MCNC Room 212
P.O. Box 12889
RTP, NC  27709-2889
(919) 248-1837
(919) 248-1455 FAX
From: paj@uk.co.gec-mrc (Paul Johnson)
Subject: Peltier Effect Heat Pumps
Reply-To: paj@uk.co.gec-mrc (Paul Johnson)
Organization: GEC-Marconi Research Centre, Great Baddow, Essex
Lines: 45
I was having a look through a couple of components catalogues when I
came across a range of Peltier Effect heat pumps intended for cooling
components.  For those who have not heard of this effect, you put a
current through one of these devices, and it pumps heat from one side
to the other.  Reverse the current and you reverse the effect.  I
think a temperature difference can give you an EMF as well.
Anyway, it struck me that you could make a nice cool/hot box for
picnics with one of these, a power regulator, a thermostat and a
couple of heat sinks.  The biggest device can shift 60W with an
efficiency of 80-90%, which ain't bad (although it would flatten my
car battery in about half an hour).
Unfortunately the catalogue didn't list anything more than the basic
specs as a heat pump.  I imagine that you would get a back-EMF as the
temperature gradient across the device increases.  If so, presumably
its power decreases as the back-EMF increases, until eventually we
have a steady state with no current being consumed (assuming no
leakage).  If so, then the final temperature difference between the
two sides could be set by the supply voltage and nothing more
(although that would be a lousy way to control it).
What I would like to know is:
1: Are the above guesses correct?
2: What is the open-circuit thermal resistance of a typical device?
(I just want to be sure that my coolbox is not going to get warm
too fast when I unplug it)
3: How does a Peltier Effect heat pump actually work?  It looks like
magic!
4: Why don't they use these things in domestic fridges/freezers?
Thanks in advance,
Paul.
Paul Johnson (paj@gec-mrc.co.uk).	    | Tel: +44 245 73331 ext 3245
--------------------------------------------+----------------------------------
These ideas and others like them can be had | GEC-Marconi Research is not
for $0.02 each from any reputable idealist. | responsible for my opinions
From: sciamanda@edinboro.edu
Subject: Re: Outdoor FM Antennas
Organization: Edinboro University of PA
Lines: 25
In article <beerb.9.0@ccmail.dayton.saic.com>, beerb@ccmail.dayton.saic.com (Bradlee Beer) writes:
> I'm interested in buying or building an omnidirectional antenna for the
> commercial FM band (88-108MHz).  The commonly sold ones are a folded dipole
> bent in an "S" shape; and one with a pair of crossed dipoles.  I don't see
> either of these designs as exhibiting any gain, and they probably aren't
> truely omnidirectional.
>
>
> I'm intrigued by the discone antenna.  Does anyone have detailed information
> on how to design one for the FM band (with 75-ohm impedence)??  Is one
> commercially available??  Are there other designs that have GAIN??
>
> I already own a 10-element FM yagi.  It works great, but requires frequent
> rotation for those distant stations.
>
> Brad Beer,  4414 Castle Gate Drive,  Beavercreek, OH  45432-1814
Brad,
For an antenna, gain is synonymous with directionality.  The only way
to get gain (>1) out of an antenna is to design in directionality. The
"gain" of an antenna is defined as the signal increase (for a preferred
direction) over the signal obtained by an isotropic antenna.
Bob Sciamanda
Edinboro Univ of PA
From: row0@ns1.cc.lehigh.edu (RICHARD O. WHITE)
Subject: Re: Help with ultra-long timing
Organization: Lehigh University
Lines: 49
In article <1993Apr5.083324.48826@kuhub.cc.ukans.edu>, wellison@kuhub.cc.ukans.e
du writes:
>I have a project that was drooped in my lap that is somewhat a pain to design.
>What I am looking for is a stable ultra-long solid state timer. What they want
>to do is to place this thing on the Antartic ice shelf and measure the amount
>of snow fall over a period of six weeks. Every two weeks, they want to trip a
>selonoid to discharge different colored pellets by gas pressure out across the
>snow. Then by digging down into the snow, the snow fall amount can be measured
>as they come to the different color pellets.
>
>The problem is trying to build a timer that would stand the cold (-40 degrees)
>and a power source that wouldn't drain. I have looked at the XR-2204 timers and
>the standard NE556 dual timers, but thier temp specs won't go that low. Also,
>two weeks equates to 1,209,600 seconds per firing, which means one big timing
>cap ! I have found 2.2 farad (yes, Farad !) caps that have a working voltage of
>5 volts and are small in size. But again, the time of discharge at -40 or lower
>degrees isn't linear. I was thinking of using several timers chained together
>to fire the selonid at the end of the timing period, but that blasted cold and
>the drain on a battery over six weeks is the pain. One possibility would be to
>use solar panels, but this is during the six month twilight. Anyone have any
>good ideas ?
>
>Thanks in advance...
>
>-=-= Wes =-=-
>
just a suggestion:
take a motorola mc14536B set it up to give you a pulse once every sec or ten
secs with either a RC or xtal clock input. then feed to a MC14521B as clock
input and decode output for 1,209,600 sec output ,might have to add a few 'and'
gates or decoder chips to get output and reset pulse back to the'521 to restart
cycle... Trigger a oneshot from the decoded riseing edge ;the one shot then
goes to a mosfet to drive the mechanism to fire the pellet launcher..
these ckts require uAmps of current,between 5 - 15 volts, so a 12 volt
gel cell of a few Amphours would last the six weeks.
Then take the ckt board & battery wrap in 3" or 4" of foam or build a box
of out of the stuff...with plywood or metal exterior...
build a small heater out of 10-50 Watt resistors in series to keep the battery
and ckts warm.
2nd thought use 2 batteries one for heater one for timer and pellet trigger.
Insolate-insolate.......even though the chips state that the - AL
rated devices are good to -55 C.. The batteries have a considerable reduction
in capacity...oh make sure the area inside has minium air leakage..
hope this helps
RW     ( is this to long winded for the net??)(be gentle)...
--
From: rg@futserv.austin.ibm.com (R.G. Keen)
Subject: Re: All Electronics Press and Peel PCB transfer
Reply-To: ...futserv.austin.ibm.com!rg
Organization: IBM Coporation - Advanced Workstations and Systems.
Lines: 12
I think there is a huge difference in the materials and
process for printer/toner PCB's. I get first time, everytime
results from a local HP Postscript, and hardly ever works from
copies of the same artwork. The printer results are so good
that I have quit even looking for PC board processes. If I had
to use the copier version, I would think I would look elsewhere.
The moral? Experiment and find what works. Toner transfer CAN
give excellent results. It, like any process, gives erratic
results with variable inputs.
R.G.
From: fsset@bach.lerc.nasa.gov (Scott Townsend)
Subject: Electric power line "balls"
Nntp-Posting-Host: bach.lerc.nasa.gov
Organization: NASA Lewis Research Center [Cleveland, Ohio]
Distribution: usa
Lines: 18
I got a question from my dad which I really can't answer and I'd appreciate
some net.wisdom.
His question is about some 18-24" diameter balls which are attached to
electric power lines in his area.  He's seen up to a half dozen between
two poles.  Neither of us have any experience with electric power distribution.
My only guess was that they may be a capacitive device to equalize the
inductance of the grid, but why so many between two poles?.
Anyone know what they really are?  Is there a related FAQ for this?
Is there a better group to submit to?
We'd both appreciate some enlightenment.
--
Scott Townsend,  Sverdrup Technology Inc.  NASA Lewis Research Center Group
fsset@bach.lerc.nasa.gov
From: jack@multimedia.cc.gatech.edu (Tom Rodriguez)
Subject: composite video - what are HD and VD?
Article-I.D.: multimed.JACK.93Apr6032642
Organization: Multimedia Computing Group
Lines: 19
I've got an rgb Mistubishi monitor and on the back it has 5
BNC connectors labeled like this:
composite
HD          VD
+           +        +       +       +
sync     red    green    blue
I've used it as a straight RGB monsitor but i can't figure out
how to use it for composite.  Could someone explain what these markings
mean?  Thanks for any help.
tom
--
Tom Rodriguez  (jack@cc.gatech.edu)
Multimedia Computing Group - GVU Lab
Georgia Institute of Technology
Atlanta, Georgia 30332-0280
From: gerg@netcom.com (Greg Andrews)
Subject: Re: Radar detector DETECTORS?
Organization: Netcom Online Communications Services (408-241-9760 login: guest)
Lines: 25
nhowland@matt.ksu.ksu.edu (Neal Patrick Howland) writes:
>
>From what I understand about radar dectectors all they are is a passive
>device much like the radio in your car.  They work as an antenna picking
>up that radar signals that the radar gun sends out.  Therefore there would
>be no way of detecting a radar detector any more than there would be of
>detecting whether some one had a radio in their car.
>
Unfortunately, you're wrong on both counts.  The most common method of
implementing a tunable receiver is to have a local oscillator.  The
local oscillator's frequency can be radiated out of the receiver via
the antenna unless the circuit is designed and constructed with great
care.
For a reference on detecting radios, get the paperback book _Spy Catcher_.
The author discovered how to detect radio receivers from their local
oscillator emissions back in the *1950s* while he worked for British
Intelligence.
-Greg
--
:::::::::::::::::::  Greg Andrews  gerg@netcom.com  :::::::::::::::::::
Fortune Cookie:  Radioactive cats have 18 half-lives.
:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
From: behnke@FNALF.FNAL.GOV (M.L. 'Broomen' Behnke)
Subject: Re: Peltier Effect Heat Pumps
Organization: Fermi National Accelerator Lab
Lines: 66
Reply-To: behnke@FNALF.FNAL.GOV
NNTP-Posting-Host: fnalf.fnal.gov
In article <2745@snap>, paj@uk.co.gec-mrc (Paul Johnson) writes:
>
>I was having a look through a couple of components catalogues when I
>came across a range of Peltier Effect heat pumps intended for cooling
>components.  For those who have not heard of this effect, you put a
>current through one of these devices, and it pumps heat from one side
>to the other.  Reverse the current and you reverse the effect.  I
>think a temperature difference can give you an EMF as well.
>
>Anyway, it struck me that you could make a nice cool/hot box for
>picnics with one of these, a power regulator, a thermostat and a
>couple of heat sinks.  The biggest device can shift 60W with an
>efficiency of 80-90%, which ain't bad (although it would flatten my
>car battery in about half an hour).
>
So-Called Cool-Hot boxes have been advetised for several years.  I recall
Damark advertising them in a recent catalog.  Problem with the units is they do
a sh***y job of keeping food cold/warm.  The peliter devices used just don't
seem to have enough punch to keep up.  If you want something hot, you need to
heat it up before you put it in the box, and end up hours later with food thats
only moderately warm.  Same goes for cold items.
>Unfortunately the catalogue didn't list anything more than the basic
>specs as a heat pump.  I imagine that you would get a back-EMF as the
>temperature gradient across the device increases.  If so, presumably
>its power decreases as the back-EMF increases, until eventually we
>have a steady state with no current being consumed (assuming no
>leakage).  If so, then the final temperature difference between the
>two sides could be set by the supply voltage and nothing more
>(although that would be a lousy way to control it).
>
>What I would like to know is:
>
>1: Are the above guesses correct?
>
>2: What is the open-circuit thermal resistance of a typical device?
>   (I just want to be sure that my coolbox is not going to get warm
>   too fast when I unplug it)
You'de probably be better off getting a good Coleman(tm) cooler and stocking
up on "blue ice" blocks.
>
>3: How does a Peltier Effect heat pump actually work?  It looks like
>   magic!
>
>4: Why don't they use these things in domestic fridges/freezers?
>
Same as above.  Not enough "punch" in them to keep/get things cold/hot.
>
>Thanks in advance,
>
>Paul.
>
>Paul Johnson (paj@gec-mrc.co.uk).	    | Tel: +44 245 73331 ext 3245
>--------------------------------------------+----------------------------------
>These ideas and others like them can be had | GEC-Marconi Research is not
>for $0.02 each from any reputable idealist. | responsible for my opinions
Mike Behnke             | Senior Tech/Advisor | Quid est illuidin aqua??
Fermi Nat Accel Lab     | Equipment Suuport   |
Batavia, Il.            | Computing Div       | PISTRIX!!  PISTRIX!!
BEHNKE@FNALF.FNAL.GOV   |                     |
My opinions are my own, not of the lab. So, if you don't like them, call
1-800-UWH-INER
From: sidhu@ee.ualberta.ca (Kenneth Sidhu)
Subject: Dimming Incand. Lamps
Article-I.D.: kakwa.1993Apr6.221848.6569
Reply-To: sidhu@ee.ualberta.ca (Kenneth Sidhu)
Organization: University of Alberta Electrical Engineering
Lines: 22
Nntp-Posting-Host: bode.ee.ualberta.ca
What's the latest and greatest way to dim incandescent lamps ?
March '93 Circuit Cellar has part one of an article about
dimming 120VAC lamps, but it seems to lead into phase-
control as the best method for controlling brightness.
I've always hated phase-control for the RFI, buzzing
filaments and non-linear adjustment range. I had
heard that you can modulate the AC line on a cycle by
cycle basis to get better results. To cut the lamp's
power to 50% you would givemsay 20 cycles of AC, then
nothing for another 20 cycles. I wonder if anyone has
tried this or knows what the pro stuff is using. Any
advice is appreciated!
Ken
email: sidhu@bode.ee.ualberta.ca
From: gtalatin@vartivar.ucs.indiana.edu  (Gerard V. Talatinian)
Subject: Low cost oscilloscopes?
Nntp-Posting-Host: vartivar.ucs.indiana.edu
Reply-To: gtalatin@ucs.indiana.edu
Organization: Indiana University
Lines: 12
I am looking at buying a low cost (< $500) scope for general purpose use.
Any recommendations? Is this info in a faq somewhere?
Any pointers appreciated.
Thanks,
-Gerard.
******************************************************************
* Gerard Talatinian                 |                            *
* Network Systems                   |   gtalatin@ucs.indiana.edu *
* University Computing Services     |   FAX:   (812) 855-8299    *
* Indiana University                |   Voice: (812) 855-0962    *
******************************************************************
From: ritley@uimrl7.mrl.uiuc.edu ()
Subject: SEEKING THERMOCOUPLE AMPLIFIER CIRCUIT
Reply-To: ritley@uiucmrl.bitnet ()
Organization: Materials Research Lab
Lines: 17
I would like to be able to amplify a voltage signal which is
output from a thermocouple, preferably by a factor of
100 or 1000 ---- so that the resulting voltage can be fed
more easily into a personal-computer-based ADC data
acquisition card.
Might anyone be able to point me to references to such
circuits?  I have seen simple amplifier circuits before, but
I am not sure how well they work in practice.
In this case, I'd like something which will amplify sufficiently
"nicely" to be used for thermocouples (say, a few degrees
accuracy or better).
Any pointers would be greatly appreciated!
From: bailey@vader.egr.uri.edu (Scott Bailey)
Subject: Re: Jacob's Ladder
Summary: Jacob's Ladder and other projects
Keywords: jacob's ladder,projects,book
Organization: University of Rhode Island / College of Engineering
Lines: 30
Hi all,
I've been following this thread about jacob's ladder for a few weeks and I
happened to come across one of the best project books that I've seen in a
while.  The book "Gadgeteer's Goldmine" by Gordon McComb offers over 55
excellent low cost projects including: Jacob's Ladder, tesla coils, plasma
spheres, a Van de Graaff generator, robots, an IR scope, and several laser
projects.  The instructions come with complete part lists, warnings and
diagrams.  For those of you who are interested in building any of the above
listed projects, you should seriously consider getting this book.  The
paperback version is only $19.95 too.
For those who want more information:
Title: Gadgeteer's Goldmine!  55 Space-Age Projects
Auth:  Gordon McComb
Pub:   TAB Books
CW:    1990
ISBN:  0-8306-8360-7
0-8306-3360-X (paperback)
Price: $19.95 (paperback)
-Scott
/-----------------------------------------------------------------------------\
| Scott A. Bailey            | #include "std_disclaimer.h"                    |
| ECL Operator               |------------------------------------------------|
| Computer Engineering       | I'm just a knight who chases the moon...       |
| University of Rhode Island | Haven't caught it yet,but I haven't let that   |
| bailey@vader.egr.uri.edu   | keep me from still trying each day and night   |
| bailey@ecl1.uri.edu        |    --(----------           ----------)--       |
\-----------------------------------------------------------------------------/
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Subject: Re: What is Zero dB????
Article-I.D.: rave.1pseebINNhn6
Organization: NASA Langley Research Center and Reptile Farm
Lines: 14
NNTP-Posting-Host: grissom.larc.nasa.gov
In article <1993Apr6.092913.18724@sei.cmu.edu> rsd@sei.cmu.edu (Richard S D'Ippolito) writes:
>
>In article <1pkveuINNduk@gap.caltech.edu>, Joseph Chiu writes:
>
>> The Ohmite company was the first to characterize resistances by numbers, thus
>> our use of the Ohms...
>
>
>Yeah, right.  And the company was started by George Simon Ohmite.
That's completely inaccurate.  The ohm was an original standard made equal
to a the resistance of a standardized electric stove heating element.  That's
where the song "Ohm on the Range" came from, of course.
--scott
From: zstewart@nyx.cs.du.edu (Zhahai Stewart)
Subject: Re: Police radar....Just how does it work??
X-Disclaimer: Nyx is a public access Unix system run by the University
of Denver for the Denver community.  The University has neither
control over nor responsibility for the opinions of users.
Organization: Nyx, Public Access Unix at U. of Denver Math/CS dept.
Lines: 13
>The father of a friend of mine is a police officer in West Virginia.  Not
>only is his word as a skilled observer good in court, but his skill as an
>observer has been tested to be more accurate than the radar gun in some
>cases . . ..  No foolin!  He can guess a car's speed to within 2-3mph just
>by watching it blow by - whether he's standing still or moving too!  (Yes,
1) How was this testing done, and how many times?  (Calibrated speedometer?)
2) It's not the "some cases" that worry me, it's the "other cases" :-)
(eg: suboptimal viewing conditions; even the best subjective viewer can only
partial compensate for certain distortions and optical illusions).
From: gleasokr@rintintin.Colorado.EDU (Kris Gleason)
Subject: Re: Electric power line "balls"
Nntp-Posting-Host: rintintin.colorado.edu
Organization: University of Colorado, Boulder
Distribution: usa
Lines: 23
fsset@bach.lerc.nasa.gov (Scott Townsend) writes:
>I got a question from my dad which I really can't answer and I'd appreciate
>some net.wisdom.
>His question is about some 18-24" diameter balls which are attached to
>electric power lines in his area.  He's seen up to a half dozen between
>two poles.  Neither of us have any experience with electric power distribution.
>My only guess was that they may be a capacitive device to equalize the
>inductance of the grid, but why so many between two poles?.
>Anyone know what they really are?  Is there a related FAQ for this?
>Is there a better group to submit to?
>We'd both appreciate some enlightenment.
I think those are to make the lines more visible to airplanes and
helicopters... cheaper than blinking red lights.
'course I could be wrong.
Kris
From: depolo@eniac.seas.upenn.edu (Jeff Depolo)
Subject: Need manual for HP 1740 scope
Organization: University of Pennsylvania
Lines: 14
Nntp-Posting-Host: eniac.seas.upenn.edu
I have a HP 1740 scope that (I think) has a problem in the HV section.
Symptom: started turning on and off on its own, making intermittant
bright flashes on the CRT, and then finally, passed away.  If you
have a manual (or any suggestions), please send me mail.  Will gladly
pay reproduction/shipping costs plus a little $ for your efforts for
the manual.  Thanks in advance.
--- Jeff
--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Jeff DePolo  WN3A              Twisted Pair: (215) 337-7383H  387-3059W
depolo@eniac.seas.upenn.edu    RF: 443.800+ MHz    442.700+ MHz    24.150 GHz
University of Pennsylvania
From: mneideng@thidwick.acs.calpoly.edu (Mark Neidengard)
Subject: Re: What is Zero dB????
Article-I.D.: zeus.1993Apr06.232039.106816
Organization: Academic Computing Services, Cal Poly San Luis Obispo
Lines: 13
>>: The Ohmite company was the first to characterize resistances by numbers, thus
>: our use of the Ohms...
>
>I don't know about this one, but it doesn't sound right.
DAMN RIGHT it doesn't!  Ohm's come from the greek letter omega, which
is used for resistance/impedance.
Of course, the original poster MAY have been being facetious (let's hope
so).
Mark Neidengard
mneideng@cosmos.acs.calpoly.edu
From: jimc@tau-ceti.isc-br.com (Jim Cathey)
Subject: Re: few video questions
Organization: Olivetti North America, Spokane, WA
Lines: 28
In article <7480224@hpfcso.FC.HP.COM> myers@hpfcso.FC.HP.COM (Bob Myers) writes:
>situation sometimes called "block" sync).  You can generate such a combined
>(or "composite") sync in two simple ways - OR the H. and V. syncs together,
>which gives you the non-serrated "block" sync, or EXOR them, which makes
>serrations.  (Try it!)  Actually, the EXOR doesn't really do kosher serrated
>sync, since it puts the rising (and falling, for that matter) edge of the H.
>sync pulse off by a pulse width.  But that usually makes no difference.
Sometimes.  It depends on your monitor and your timing.  If you don't
have enough vertical front porch and you use XOR composite sync you can
get even/odd tearing at the top of the screen, which is very sensitive
to the HHOLD control.  It looks like what you would expect if you
scanned the even fields (say) onto a sheet of mylar and had pinched the
upper left corner with your fingers and started to tear it off the tube.
With proper composite sync (equalizing pulses) the interlace is rock
solid.
--
+----------------+
! II      CCCCCC !  Jim Cathey
! II  SSSSCC     !  ISC-Bunker Ramo
! II      CC     !  TAF-C8;  Spokane, WA  99220
! IISSSS  CC     !  UUCP: uunet!isc-br!jimc (jimc@isc-br.isc-br.com)
! II      CCCCCC !  (509) 927-5757
+----------------+
One Design to rule them all; one Design to find them.
One Design to bring them all and in the darkness bind
them.  In the land of Mediocrity where the PC's lie.
From: dzenc@hal.gnu.ai.mit.edu (Dan Zenchelsky)
Subject: VIdeotext/teletext descrambler
Article-I.D.: hal.1psvcg$1auv
Distribution: world
Organization: dis
Lines: 9
NNTP-Posting-Host: hal.ai.mit.edu
Hi,
I am looking for a PC card which does european videotext/teletext
descrambling (PAL). Does anyone in the US sell such a card? I once
saw an article about a card with the same functionallity in a
european Elektor magazine, but I wasn't able to track it down.
Thanx in advance,
Dan
From: babb@sciences.sdsu.edu (J. Babb)
Subject: Re: Electric power line "balls"
Article-I.D.: larc.babb-060493164354
Distribution: usa
Organization: SDSU - LARC
Lines: 16
NNTP-Posting-Host: larc.sdsu.edu
In article <1993Apr6.203237.20841@eagle.lerc.nasa.gov>,
fsset@bach.lerc.nasa.gov (Scott Townsend) wrote:
>
> I got a question from my dad which I really can't answer and I'd appreciate
> some net.wisdom.
>
> His question is about some 18-24" diameter balls which are attached to
> electric power lines in his area.  He's seen up to a half dozen between
> two poles.  Neither of us have any experience with electric power distribution.
> My only guess was that they may be a capacitive device to equalize the
> inductance of the grid, but why so many between two poles?.
I'll bet there's a runway nearby.
Jeff Babb
babb@sciences.sdsu.edu   babb@ucssun1.sdsu.edu
Programmer, SDSU - LARC
From: smithr@teecs.UUCP (Robert Smith)
Subject: Re: Conductive Plastic, what happened?
Organization: Litton Systems, Toronto ONT
Lines: 7
If you're thinking of reactive polymers they're making ESD safe
contauiners out of it. As far as being conductive goes anything with
a resistance less than 10 to the fouthrth power ohms per cubic measure
is classed as conductive per MIL-STD-1686 for ESD protection. My $0.02
($0.016 US).
Bob.
From: young_dick@macmail2.rtsg.mot.com (Dick Young)
Subject: ATTN: H. Wheaton, UCal Davis
Nntp-Posting-Host: 136.182.211.36
Organization: Motorola, Inc. (Cellular Infrastructure)
Distribution: usa
Lines: 11
I tried to E-mail you, but the message bounced.
Motorola has a University Support Program through which (I've been told) folks
at schools can get sample quantities of parts.  If you'd like to try this
route, e-mail me for the address/phone #...I don't wish to post it for all the
world to see.
Dick Young
Motorola, Inc.
(Who doesn't have a thing to do with my opinions: They're my own fault.)
From: advax@reg.triumf.ca (A.Daviel)
Subject: Re: Radar detector DETECTORS?
Organization: TRIUMF: Tri-University Meson Facility
Lines: 24
Distribution: world
NNTP-Posting-Host: reg.triumf.ca
News-Software: VAX/VMS VNEWS 1.41
In article <1pslckINNmn0@matt.ksu.ksu.edu>, nhowland@matt.ksu.ksu.edu (Neal Patrick Howland) writes...
>
>From what I understand about radar dectectors all they are is a passive
>device much like the radio in your car.  They work as an antenna picking
>up that radar signals that the radar gun sends out.  Therefore there would
>be no way of detecting a radar detector any more than there would be of
>detecting whether some one had a radio in their car.
>
From my rather rusty knowledge of radio, most radio receivers use a superhet
circuit, so that the incoming signal is mixed with a local oscillator, giving
a fixed intermediate frequency (IF) that is more easily amplified. The
detector detectors work by picking up IF re-radiated from your radar
detector. In Britain, where one has/used to pay for a TV licence, there
are/were TV detector vans prowling the streets, looking for people who hadn't
paid their licence fee. They had a couple of long solenoid antennae on the
roof, and I believe could triangulate an operating TV from the IF.
I wonder how much of the IF is radiated back from the detector antenna, and
how much from the rest of the module. It might be worth putting the detector
in a proper RF shielded enclosure.
--
Andrew Daviel, Vancouver, Canada <advax@triumf.ca>
finger advax@reg.triumf.ca for PGP key
From: mark@wdc.sps.mot.com (Mark Shaw)
Subject: Re: Rumors
Nntp-Posting-Host: 223.199.55.11
Organization: Motorola Western MCU Design Center, Chandler Arizona
Lines: 17
In article <1993Apr2.174851.22659@cs.unca.edu>, kepley@photon.phys.unca.edu (Brad Kepley) writes:
|> I just heard an unbelievable rumor that Motorola has decided to drop their
|> integrated circuit manufacture business.  Apparently a Digikey rep called
|> one of our production coordinators, for out information so that we could
|> make plans to deal with this, that Moto was getting out.  Anybody else
|> get a call about this?
|>
|> Too much for me.  It's about like Intel announcing they were getting out
|> of the IC business.
This rumor didn't happen to appear on April 1st?
If this DigiKey rep was serious, I think I will buy my parts elsewhere.
If that is the way they do business, you cannot trust them.
Mark
From: Joseph N Hosteny <jh8e+@andrew.cmu.edu>
Subject: Re: Electric power line "balls"
Organization: Freshman, Electrical and Computer Engineering, Carnegie Mellon, Pittsburgh, PA
Lines: 5
Distribution: usa
NNTP-Posting-Host: andrew.cmu.edu
In-Reply-To: <1993Apr6.203237.20841@eagle.lerc.nasa.gov>
Do you know if there is an airport nearby? They may just be markers
to tell pilots of small planes that there are power lines nearby.
/Joe
From: ubsiler@msuvx1.memst.edu
Subject: Home-made IR remote extender
Organization: Memphis State University
Lines: 19
Here's a question for all you electrical engineers out there:
I bought an 'Infrared detector module' at Radio Shack for $3.95 - it is a
little gizmo that senses infrared remotes and produces an output signal. Then
I hooked the output through a transistor to an infrared LED. The circuit works
like a minature remote control extender in my car - All remote commands are
relayed to the CD player hidden in the glove compartment. It works fine with
my Denon CD player, but when I tried to build the same circuit for a friend's
VCR, it didn't work.
The circuit appears to work for other remotes (you can see infrared with a
Sony CCD camcorder) but coincidentally it only seems to work for my CD
player...
Any advice would be appreciated....
Brian
---
UBSILER @ MSUVX1.MEMST.EDU
From: et@teal.csn.org (Eric H. Taylor)
Subject: Holes: practical questions, was - Philosophical Question
Summary: How do we preferentially amplify holes instead of electrons?
Keywords: holes electrons semi-conductors mobility
Nntp-Posting-Host: teal.csn.org
Organization: 4-L Laboratories
Expires: Sun, 9 May 1993 06:00:00 GMT
Lines: 48
In article <12426@sun13.scri.fsu.edu> jac@ds8.scri.fsu.edu (Jim Carr) writes:
>[...]
>I agree.  I come at this from nuclear physics, where one often discusses
>particle-hole excitations and certain reactions have the effect of
>applying an annihilation operator and creating a hole, and it is a
>subtle question.  The longer one works with them, the more real they
>become.  There are also quasi-particles, which raise the same sort
>of question about how "real" the entity is.  The phenomenon is most
>certainly a real one.
OK, I've asked this before, and with a new thread on these lines, I
ask this again:
1: If a large hole current is run thru a resistor, will there be
I^2 * R cooling instead of heating?
2: Can anyone design an amplifier that preferentially amplifies
hole currents over normal electron currents?
3: what semiconductor materials have the highest ratio of
hole mobility to electron mobility? (please quote actual
test samples rather than estimates based on theory. Also,
don't be limited to semiconductors: consider also insulators,
resistors, dielectrics, piezo-electrics, conductors,
magnets (metal, ceramic), magnetostrictives, etc).
NOTES:
to summarize, this thread has so far stated that the only area
where holes are not detectable is the vacuum. That is, hole
particles only exist in the presence of matter.
Previous threads have stated that holes only exist in certain
semi-conductors. The question that naturally arises is if
the hole currents inside a semi-conductor vanish at the point
where the semiconductor is joined to a conductor (say, copper).
I don't want a theoretical discussion here about whether
holes could exist inside metal conductors, rather I ask for
an experimental discussion on how to amplify and detect such
currents *if* they exist.
Also note that I have cross-posted this to sci.electronics
since this is now becoming an electronic discussion.
Thanx,
Eric.
----
ET   "A Force of Nature"
----
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Need tone decoder circuit
Organization: U of Toronto Zoology
Lines: 14
In article <5170286@hplsla.hp.com> tomb@hplsla.hp.com (Tom Bruhns) writes:
>>Does anybody out there have a circuit that will decode a 1000Hz tone?
>
>Use a NE567 tone decoder PLL chip...
My impression -- it's not an area I've played with much -- is that the
much-beloved NE567 is basically obsolete.  If you want to detect a 1kHz
tone, set a switched-capacitor filter chip to that frequency, feed your
input to it, and see if anything comes out the other end.  The NE567 was
what you used when good clean bandpass filters were hard to do; nowadays
they're easy, and the results are better.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
- Kipling           |  henry@zoo.toronto.edu  utzoo!henry
From: heuvel@neptune.iex.com (Ted Van Den Heuvel)
Subject: Motorola MC143150 and MC143120
Originator: heuvel@neptune.iex.com
Organization: iex
Lines: 6
Does anyone out there know of any products using Motorola's Neuron(r) chips MC143150 or MC143120. If so, what are they and are they utilizing Standard Network Variable Types (SNVT)?
_________________________________________________________________________________
Ted Van Den Heuvel   heuvel@neptune.iex.com
KX5P
From: rich1@netcom.com (Richard Soennichsen)
Subject: Re: electronic odometers (was: Used BMW Question ..... ???)
Organization: Netcom Online Communications Services (408-241-9760 login: guest)
Lines: 1
The Bmw speedo is triggered by a reed switch\magnet assembly in the differential. I would think that this signal would be easy to reproduce.
From: obrien@hri.com (Jim Obrien)
Subject: IBM-PC XT switch settings
Organization: Horizon Research, Inc.
Lines: 7
Distribution: world
Reply-To: obrien@bigbird.hri.com
NNTP-Posting-Host: sparc28.hri.com
I just got an IBM-PC XT with no documents. Its a true
IBM, and I was wondering if anyone had the definitions
of the 2 8 position dip switches?
- thankx Jim
From: bell@hops.larc.nasa.gov (John Bell)
Subject: Re: Adcom cheap products?
Organization: NASA Langley Research Center
Lines: 21
NNTP-Posting-Host: hops.larc.nasa.gov
In article <mdonahue.15x9@amiganet.chi.il.us> mdonahue@amiganet.chi.il.us (Mike Donahue) writes:
>
>As for Adcoms Mobil, They are going with amps that canb use Balanced Inputs, a
>VERY nice toy, but I'm afraid its goig to push their amps beyound resonable
>price ranges.  especialy because taking advantage of those balanced inputs
>requires a $120+ RCA to Balanced adapter...
Umm, when I was doing sound reinforcement for a living, I used to get direct boxes (which convert
unbalanced 1/4" jacks to balanced XLRs) for about $25 each, or a little more for higher
quality. You'll need two for a stereo signal, of course, and a little adapter thingy from
Radio Sh#$&^t to convert from RCA to 1/4". Total cost should be around $50. You can also buy
transformers for quite a bit less and wire them yourself. Total cost there should be under $30.
You can get all this stuff from any pro music shop that sells sound reinforcement gear.
The benefit? NO noise that you can hear will be generated in the cables going to the component
with the balanced inputs, even when you run them in bad places, like next to power lines.
-----
John Bell
NASA Langley Research Center
bell@hops.larc.nasa.gov
From: moffatt@bnr.ca (John Thomson)
Subject: Re: Telephone on hook/off hok ok circuit
Nntp-Posting-Host: bcarhdd
Organization: Bell-Northern Research, Ottawa, Canada
X-Newsreader: TIN [version 1.1 PL6]
Lines: 37
Tony Kidson (tony@morgan.demon.co.uk) wrote:
: In article <oHZs2B2w164w@k5qwb.lonestar.org> lrk@k5qwb.lonestar.org writes:
:
: >mcovingt@aisun3.ai.uga.edu (Michael Covington) writes:
: >
: >> In article <1ptolq$p7e@werple.apana.org.au> petert@zikzak.apana.org.au (Peter
: >> >
: >> >Just a thought of mine here:
: >> >Since an on-hook line is aprox 48-50V, and off-hook it usually drops below 1
: >> >How about an LED in series with a zener say around 30V.
: >> >On-hook = LED on
: >> >Off-hook = LED off.
: >> >Would this work? If anyone tries/tried it, please let me know.
: >>
: >> Aye, there's the rub -- if you draw enough current to light an LED, the
: >> equipment at the phone company will think you've gone off hook.
: >> In the on-hook state you're not supposed to draw current.
: >
: >Which means you should just use your Digital VoltMeter. You can use an
: >old VOM but the phone company equipment can detect that and might think
: >there's something wrong with the cable.
: >
:
: Look Guys, what's the problem here?  If you want a light that goes on when
: the 'phone is *Off* hook, all you need it to run it in *series* with the
: line, as I mentioned in my previous post.  If you want a light that goes on
: when the 'phone is *on* hook, all you need is a voltage threshold detector.
If you're going to do the series Diode thing (which is the easiest), just
make sure that the LED can take the current (I can't recall it off-hand, but
it's something like 100mA or more?)
Greggo.
Greg Moffatt  moffatt@bnr.ca
Bell-Northern Resarch Inc., Ottawa Canada
"My opinions; not BNR's"
From: dgj2y@kelvin.seas.Virginia.EDU (David Glen Jacobowitz)
Subject: Dumb Question: Function Generator
Originator: dgj2y@kelvin.seas.Virginia.EDU
Organization: University of Virginia
Lines: 35
I have a new scope and I thought I'd save a few bucks by
buying one with a function generator built in. After having it awhile
I noticed two things about the function generator. For one, there
seems to be a bias even when the 'pull-offset' is pushed in. That is,
I have to pull that know and adjust it to get a signal sans some
random 50mV bias.
The other _really_ annoying thing is that the damn output
won't go below about 1V p-p. I am a student ( you may have guessed
from my previous posts ), and I often have to measure the input
impedances of various circuits I build.Many of the circuits have
maximum input signals of way less than 500mV amplitude and most have
input impedances in the 10's of Kohm range. The thing is, in order to
use my function generator I have to divide the voltage to some thing
reasonable. Then, of course, to measurethe input impedance of my
circuit I am going to have to throw in another resistor in series.
With the 50ohm output of the generator I could just ignore it, but now
with this little divider there I have to figure that in. It's kind of
a pain in  the ass.
Is there any way I could make myself a little box that could
solve this little problem. The box would tkae the function generator
input, lower the voltage and give an output impedance that is some
low, unchanging number. I would want to lower the voltage by a factor
of one hundred or so. I could just build a little buffer amp, but I'd
like to have this box not be active.
Any quick ideas. The scope's not broken. For other reasons I
had sent it to the shop to get repaired and they replaced it. The
function generator was the same way on that one, too.
please help as I am feeling very stupid
today,
dave
dgj2y@virginia.edu
From: rky57514@uxa.cso.uiuc.edu (Tall Cool One )
Subject: Can I use a CD4052 analog multiplexer for digital signals?
Organization: University of Illinois at Urbana
Lines: 14
As the subject says - Can I use a 4052 for digital signals?  I don't see
why it couldn't handle digital signals, but I could be wrong.  Anyone have
any advice?  Thanks.
_I_______________________________________________________________________I_
(_@_)                                                                   (_@_)
|   |   Raymond Yeung               Internet: Nimbus@uiuc.edu           |   |
|   |                                         rky57514@uxa.cso.uiuc.edu |   |
|   |   EE student at the                                               |   |
|   |   University of Illinois    CompuServe: 70700,1011                |   |
|   |   at Urbana-Champaign                                             |   |
(___)-------------------------------------------------------------------(___)
I                                                                       I
From: sciamanda@edinboro.edu
Subject: Re: Emergency Vehicle Sensors?  traffic-light-phreaks?
Organization: Edinboro University of PA
Lines: 21
In article <LINNIG.93Apr7154239@m2000.dseg.ti.com>, linnig@m2000.dseg.ti.com (Mike Linnig) writes:
> Folks,
>
> Here in the Dallas area I have noticed that it is quite common to see an odd
> "sensor" on top of traffic lights.  These have been here for at least six
> years.  I've often wondered what they are.
> . . .
> Mike Linnig, Texas Instruments Inc. | 97.43% of all statistics are made |
> - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Here in Erie, PA there is a system in the inner city called Rado-Lite (a
trade name) which allows police and ambulance vehicles to gain right of
way by controlling traffic lights through RADIO signals.  The receivers
look much like what you describe, but they include a UHF whip antenna (less
than a foot tall) and a light which flashes on and off to let traffic know that
an emergency vehicle has taken control and is approaching.  Local folklore
says this system was invented here; I don't know if this company has any
other installations.  It has been in operation for at least 30 years, going
only by my memory.
Bob Sciamanda
Edinboro Univ of PA
From: fmg@alpha.smi.med.pitt.edu (Filip Gieszczykiewicz)
Subject: FAQ - corrections
Summary: PCB correction, FTP site, etc
Organization: Medical Informatics, Pittsburgh, PA USA
Lines: 29
Greetings. I received a reply stating that unless someone else
confirms that the following company is operating, I should
remove it from my lst:
>PCB Prototypes of Sandy, UT
>Ronald Baker
>8195 South 2660 East
>Sandy, UT  84093
>Tel: [read below]
This is from the COMM_PCB.FAQ (commercial PCB makers).
Also, I don't have time to get the FAQ onto the sci.answers
because of what I like to refer to is "red tape" - after the
finals, I'll see what I can do... in the mean-time, anyone know
of an FTP site that wouldn't mind a 250K file? :-)
And last, I have some new entries for the SIMUSOFT list (mostly
commercial/institutional stuff) but was wondering: should I keep
the restrictions on the price of the software to be considered ->
under $600 or should I include all those in 4 digit prices also?
Take care.
--
/ Filip "I'll buy a vowel" Gieszczykiewicz. | Best e-mail "fmgst+@pitt.edu"  \
| All ideas are mine but they can be yours for only $0.99 so respond NOW!!!! |
| I live for my EE major, winsurfing, programming, SCA, and assorted dreams. |
\ 200MB Drive - Linux has 100MB and MS-DOS has 100MB. MS-DOS is worried ;-)  /
From: cab@col.hp.com (Chris Best)
Subject: Re: Illusion
Organization: your service
Lines: 15
NNTP-Posting-Host: hpctdkz.col.hp.com
> This is not a new idea.  At least 10 years ago I got this little gadget with
> a keyboard on the back and 8 LED's in a vertical row on the front.  It has a
> long handle and when you wave it in the air it "writes" the message you typed
> on the keyboard in the air.
----------
This is not news.  In fact it's where I got the idea from, since it was
such a neat item.  Mattell made it, I believe, modeled after a "space
saber" or "light sword" or something likewise theme-y.  My addition was
using a motor for continuous display, and polar effects in addition to
character graphics.  I should have protected it when I had the chance.
No one to kick but myself...
Ten years ago is about right, since I built mine in '84 or '85.
From: cab@col.hp.com (Chris Best)
Subject: Re: Need help with car stereo....
Organization: your service
Lines: 16
NNTP-Posting-Host: hpctdkz.col.hp.com
Just a shot here, but ya never know:
I once bought a (REAL) cheap equalizer / power amp for my car tape player
at one of those motel-room truckload sales, and it sounded great.  For a
while, that is.  Then one channel quit entirely.  I opened it up, and the
amplifier chip for the bad channel had simply melted some of its solder
joints attaching it to the PCB.  I soldered them back and it worked fine.
I just had to keep the volume a bit lower than I did before.  Probably
lousy heat sinking.
You said "a nice Alpine" which I'm sure is a few orders of mag higher
in quality than the P.O.S. I had.  But the point is - look inside before
you scrap it, since you OCCASIONALLY find something you can repair.
Maybe even the same thing I found.
Good luck!
From: cab@col.hp.com (Chris Best)
Subject: Re: Uninterruptible Power Supply
Organization: your service
Lines: 17
NNTP-Posting-Host: hpctdkz.col.hp.com
I'm no expert at UPS's, but you said something that made it sound like
you didn't realize something.  On a typical UPS (well, on ours, anyway),
there is NO switchover from AC to DC.  All the protected equipment is
ALWAYS running from the batteries (via an inverter), with the usual
condition of also having them on charge.  If the power fails, big deal -
the computers never see it (until the batteries start to droop, but
there's something like 60 car-sized batteries in that cabinet, so it
takes a while).
If you were gonna run the guts on straight DC instead of an inverter,
why not do it all the time?  Then there'd be no switchover to screw
things up, and no having to sense the failure fast.  Just keep the DC
on charge when the power is on, and it'll be there in zero time when
you "need" it.
Just some ideas.  Can't guarantee what'll work or not, but hope at least
SOME of this helped.
From: prasad@vtaix.cc.vt.edu (Prasad Ramakrishna)
Subject: Exploding TV!
Organization: Virginia Tech, Blacksburg, VA
Lines: 19
Distribution: usa
NNTP-Posting-Host: vtaix.cc.vt.edu
I had a GE Emerson 13" color TV for about 3 years and one fine day,
while we were watching something (I doubt if the program was the cause),
we heard a mild explosion.   Our screen went blank but there was sound,
so we thought, 'oh we have special effects on the program'.  But soon
the sound stopped and smoke started to appear at the back of the TV.
The brilliant EEs we are, we unplugged the TV and called customer service
only to be thrown around by please hold, I will transfer u to blah blah..
Finally we abandoned the idea of trying to fix the TV and got a new one
(we wanted a bigger one too!).
After all the story, what I wanted to know is: Is my problem an isolated
incident or a common one? (I recall reading about Russian TVs exploding, but
not here, in the US). Why would the picture tube explode or even smoke?
I still have the left over TV set, I might dig into it this summer. Any
idea where I can get parts for these things? (probably will cost more than TV).
W/my 0.02
Prasad
prasadr@vtvm1.cc.vt.edu
Subject: Re: Can Microwaves Be Used To Collect XYZ Coordinates
From: sldf3@sol.ee.usu.edu (Weston R Beal)
Distribution: world
Organization: Utah State Univ. EE
Nntp-Posting-Host: sol.ee.usu.edu
Lines: 32
In article <C5Hs5J.AG7@bcstec.ca.boeing.com>, rgc3679@bcstec.ca.boeing.com (Robert G. Carpenter) writes:
|> It seems reasonable to me that a microwave transmitter-receiver setup could
|> do the job. For example, say you want to map an acre lot, it'd be convenient
|> to place MW transmitters around the lot's periphery (either 2 or 3) and then
|> carry a hand-held recorder and walk to a point on the lot, press a button and
|> the coords of the recorder's location is stored as digital data.
|>
|> What's the chance of this working? Any systems like this already exist?
|> What kind of accuracy could you expect? What would something like this
|> cost to prototype? Is there a better alternative than microwaves?
Of course you could develope this system, but there is already a system called Global
Positioning Satellites.  It gives three dimensional coordinates anywhere on earth.
Many surveyors use this system with a differential receiver/transmitter to get
coordinates within centimeters.  Basic receivers with resolution of a few meters (on
a good day) are available from many sources.
--
WMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMW
\_      \_  \_\_\_    \_\_\_               Weston R Beal
\_      \_  \_    \_  \_    \_         sldf3@sol.ee.usu.edu
\_  \_  \_  \_\_\_    \_\_\_            sldf3@cc.usu.edu
\_\_  \_\_  \_  \_    \_    \_       Electrical Engineer
\_      \_  \_    \_  \_\_\_       Utah State University
"That's the wonderful thing about crayons; they can take you to
more places than a starship can."    - Guinon
From: carlos@math.lsa.umich.edu (Carlos Montenegro)
Subject: Low voltage lighting and X10 questions.
Organization: University of Michigan, Mathematics Department, Ann Arbor
Lines: 12
NNTP-Posting-Host: sirius.math.lsa.umich.edu
1. Can low Voltage lights be controlled with an X10  module by putting it
before the transformer? It seems to work, even the dimmer works. Not very
reliable. Will it damage the module? Can it be done reliably?
2. I put a motion switch (Heath) to a low voltage light, it worked but now it is
broken, too much current? How can I get arround that?
3. How can I increase the intensity of a light using the X10 PC computer
interface without having it go 100% on first and then down. I am doing
my own programing, not the X10 program.
Thanks   C. Montenegro
From: kolstad@cae.wisc.edu (Joel Kolstad)
Subject: Re: Dumb Question: Function Generator
Organization: U of Wisconsin-Madison College of Engineering
Lines: 35
In article <C5J845.3B8@murdoch.acc.Virginia.EDU> dgj2y@kelvin.seas.Virginia.EDU (David Glen Jacobowitz) writes:
>
>	I have a new scope and I thought I'd save a few bucks by
>buying one with a function generator built in.
Hmm... now where was that ad for the combination radio/hand cranked
generator/flashlight/siren I saw? :-)
[function generator has a 50mV offset, and the amplitude's too high]
>	Is there any way I could make myself a little box that could
>solve this little problem. The box would tkae the function generator
>input, lower the voltage and give an output impedance that is some
>low, unchanging number. I would want to lower the voltage by a factor
>of one hundred or so. I could just build a little buffer amp, but I'd
>like to have this box not be active.
Sure, you've already got the right idea.
Ignoring the 50 ohm internal resistance of the generator for a second, just
run it into, say, a voltage divider made of 990 ohms in series with 10
ohms.  This new circuit is the Thevenin equivalent of one that puts out
1/100 of the original voltage, and has an output impedence of negligibly
less than 10 ohms.  You may want to monkey with the values a little
depending on whether you care more about the _exact_ dividing ratio or
the availability of parts.
Hows that sound?
---Joel Kolstad
P.S. -- This is why those 1000:1 high voltage probes for multimeters can be
accurate but still cheap.  They have something like 100 megs in series with
100k, which doesn't load the (often high impedence) source much, as well as
keeping the (probably 10 meg impedance) multimeter happy.
From: wex@cs.ulowell.edu (Paul M. Wexelblat)
Subject: Re: what to do with old 256k SIMMs?
Reply-To: wex@cs.ulowell.edu
Organization: Univ. of Lowell CS Dept.
Lines: 11
In article <1993Apr15.100452.16793@csx.cciw.ca>, u009@csx.cciw.ca (G. Stewart Beal) writes:
|> >	I was wondering if people had any good uses for old
|> >256k SIMMs.  I have a bunch of them for the Apple Mac
|> >and I know lots of other people do to.  I have tried to
|> >sell them but have gotten NO interest.
We use them as Christmas tree decorations, the cat doesn't eat these.
--
...Wex
From: wex@cs.ulowell.edu (Paul M. Wexelblat)
Subject: Re: A question about 120VAC outlet wiring.. (the truth)
Keywords: outlet
Reply-To: wex@cs.ulowell.edu
Organization: Univ. of Lowell CS Dept.
Lines: 6
I suggest that misc.consumer.house is a better forum for this, several
electricians, a huge FAQ that adresses ALL the issues raised here.
--
...Wex
From: lancer@oconnor.WPI.EDU (Stephe Lewis Foskett)
Subject: How do DI boxes work?
Organization: ZikZak Corporation
Lines: 19
Distribution: world
NNTP-Posting-Host: oconnor.wpi.edu
I'm doing sound for a couple of bands around here and we need Direct
Input boxes for the keyboards.  These are the little boxes that take a
line level out of the keyboard and transform it into low-Z for the run
to the mixer.  Sadly they cost like $50 (or more) each and I'm going
to need like 5 or 10 of them!  I looked inside one (belonging to
another band) and it looks like just a transformer.  Does anyone have
any plans for building them?  Perhaps in Anderton's "Electronic
Projects for Musicians" book (which I am having a hell of a time
tracking down...)?
Thanks a lot!
.s.
PS: Post or email.  I read this group...
--
- lancer@wpi.wpi.edu -                    - 0{{  MoDiMiDoFrSaSo: -
-   Mein Kopf ist ein Labyrinth, mein Leben ist ein Minenfeld    -
From: msf@skaro.as.arizona.edu (Michael Fulbright)
Subject: Re: Analog switches/Balanced Demodulators
Distribution: na
Organization: University of Arizona UNIX Users Group
Lines: 13
caadams@atlas.cs.upei.ca (Kenny Adams) writes:
>hi,
>	instead of using a +15vdc supply for the 4066 try using a +7 and -7
>volt supply.  i have some commercial audio equipment that uses this approach
>for ground referenced audio.  they use the -7 volt supply as the logic
>ground.
In this case would the switch control voltages be -7V to turn the switch
off and >0V to turn the switch on?
michael fulbright
msf@as.arizona.edu
From: whit@carson.u.washington.edu (John Whitmore)
Subject: Re: A question about 120VAC outlet wiring..
Keywords: outlet
Article-I.D.: shelley.1qkm8iINN92t
Distribution: world
Organization: University of Washington, Seattle
Lines: 34
NNTP-Posting-Host: carson.u.washington.edu
In article <1qids1INNebl@chnews.intel.com> crichmon@sedona.intel.com (Chris Richmond) writes:
>
>In article <1993Apr14.193122.20818@mprgate.mpr.ca>, vanderby@mprgate.mpr.ca (David Vanderbyl) writes:
>> In article <1993Apr14.172145.27458@ecsvax.uncecs.edu>, crisp@ecsvax.uncecs.edu (Russ Crisp) writes:
>> |> I'm considering modernizing some old wiring in my home, and
>> |> I need a little advice on outlet wiring.  Several outlets
>> |> are the old 'two prong' type, without the ground.  Naturally,
>> |> the wire feeding these outlets is 12/2, WITHOUT the ground
>> |> wire.  I noticed at the fusebox that some circuits have the
>> |> 12/2 with ground, and that on these circuits, the ground
>> |> wire was tied to the same bus as the neutral (white) wire.
>> This is contrary to the electrical code and should be fixed.
>Well, my house was built just last year, and the breaker box is wired the
>same way.
There SHOULD be a connection of the GROUND wire to a ground
in the breaker box.  There also should be a connection of the NEUTRAL
wire to a ground in the breaker box.  There should be no other
place in the building where such a connection occurs (i.e. not in
any of the outlet boxes).
The NEUTRAL (white) wire is a 'grounding conductor' for
the plug, and is NOT safe to touch, while the GROUND (green)
wire is a 'protective ground' and carries no current unless
some kind of electrical fault has occurred.  It's safe
to touch the protective ground, but not to touch the
grounding conductor (because there is current in the grounding
conductor, its outlet-box end will not be at the same ground
potential as its breaker-box end).
John Whitmore
From: bill@thd.tv.tek.com (William K. McFadden)
Subject: Re: Cable TVI interference
Keywords: catv cable television tvi
Article-I.D.: tvnews.1993Apr15.193218.13070
Organization: Tektronix TV Products
Lines: 15
In article <VL812B2w165w@inqmind.bison.mb.ca> jim@inqmind.bison.mb.ca (jim jaworski) writes:
>What happens when DVC (Digital Videon Compression) is introduced next
>year and instead of just receiving squiggly lines on 2 or 3 channels
>we'll be receiving sqigglies on, let's see 3*10 = 30 channels eventually.
Since the digital transmission schemes include error correction and
concealment, the performance remains about the same down to a very low
carrier-to-noise ratio, below which it degrades very quickly.  Hence,
digitally compressed TV is supposed to be less susceptible to interference
than amplitude modulated TV.
--
Bill McFadden    Tektronix, Inc.  P.O. Box 500  MS 58-639  Beaverton, OR  97077
bill@tv.tv.tek.com, ...!tektronix!tv.tv.tek.com!bill      Phone: (503) 627-6920
How can I prove I am not crazy to people who are?
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Subject: Re: Where to buy parts 1 or 2 at a time?
Nntp-Posting-Host: aisun3.ai.uga.edu
Organization: AI Programs, University of Georgia, Athens
Lines: 15
The pricing of parts reminds me of something a chemist once said to me:
"A gram of this dye costs a dollar.
It comes out of a liter jar which also costs a dollar.
And if you want a whole barrel of it, that also costs a dollar."
I.e., they charge you almost exclusively for packaging it and delivering
it to you -- the chemical itself (in that particular case) was a byproduct
that cost almost nothing intrinsically.
--
:-  Michael A. Covington, Associate Research Scientist        :    *****
:-  Artificial Intelligence Programs      mcovingt@ai.uga.edu :  *********
:-  The University of Georgia              phone 706 542-0358 :   *  *  *
:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :  ** *** **  <><
From: wellison@kuhub.cc.ukans.edu
Subject: Re: electronic odometers
Article-I.D.: kuhub.1993Apr15.153153.49197
Organization: University of Kansas Academic Computing Services
Lines: 10
I had the insturment panel go out in my car (a 1990 Lincoln Contenintal) which
is a digital dash. They replaced the whole thing with a 1991 dash (thank god it
was under the warrenty ! :-) Anyway, the odometer was reading the exact milage
from the old panel. It must have a EEPROM of some sort in it that is up-dated.
Seems to me that removing the battery would erase it, but it doesn't. So I
guess they swapped the NVM chip (non-volitile memory) and installed it in the
new dash. No, they wouldn't let me have the old dash to tinker with :-(
-=-= Wes =-=-
From: harry@neuron6.jpl.nasa.gov (Harry Langenbacher)
Subject: Re: Uninterruptible Power Supply
Article-I.D.: jato.1993Apr15.225326.22831
Organization: JPL Pasadena CA
Lines: 25
Nntp-Posting-Host: neuron6.jpl.nasa.gov
In article <NURDEN1.25.734866568@elaine.ee.und.ac.za> NURDEN1@elaine.ee.und.ac.za (Dale Nurden) writes:
>I'm wanting to build a simple UPS for my PC. ... sustain the computer long enough to complete
>the current task and save, 5 to 10 minutes should be enough....
>I think, though I don't really need to keep the monitor active (I can try to
>remember what to do) so maybe I can avoid a DC-AC inverter and just use a
>battery to directly supply the motherboard and peripherals.
Now there's a good idea ! All you need is 20 amps DC for a few minutes, and
a good (wetware) memory (was I using wp or autocad or ...). I thought of the
same idea myself a few days ago. I've got a fairly new car battery that I take
along in my 4x4 when I go camping, and it sits around useless when I'm home.
I wish I could get a batteryless ups to use it with, or use it with a heavy
duty 5-volt regulator to supply the PC. But I guess you'd need -5v and -12v
(and +12) too (2 more batteries ?).
An alternative would be to leave a 40 AMP battery charger hooked up to the battery
and run a 12vdc to 110vac converter running all the time, and when the power
goes out, voi-la ! the 110vac converter keeps on running off the battery ! and
then I could take the 110vac converter and my computer on the camping trips !-)
--
Harry Langenbacher 818-354-9513 harry%neuron6@jpl-mil.jpl.nasa.gov
FAX 818-393-4540, Concurrent Processing Devices Group, Jet Propulsion
Laboratory, M/S 302-231, 4800 Oak Grove Dr, Pasadena CA 91109 USA
From: ali@cns.nyu.edu (Alan Macaluso)
Subject: MICROPHONE PRE-AMP/LOW NOISE/PHANTOM POWERED
Nntp-Posting-Host: liu.cns.nyu.edu
Reply-To: ali@cns.nyu.edu
Organization: New York University
Lines: 13
I'm looking to build a microphone preamp that has very good low-noise characteristics,  large clean gain, and incorportates phantom power (20-48 volts (dc)) for a PZM microphone.  I'm leaning towards a good, low-cost (??) instrumentation amplifier to maintain the balanced input from the microphone, for its good CMRR, internal compensation, and because i can use a minimal # of parts.
Does anyone out there have any experience, suggestions, advice, etc...that they'd like to pass on, I'd greatly appreciate it.
---
A l a n  M a c a l u s o		 	PURPLE MOON GIANTS
ali@cns.nyu.edu  				158 E. 7th. St. #B5
(212) 998-7837					NYC  10009
(212) 982-6630
From: alung@megatest.com (Aaron Lung)
Subject: Re: what to do with old 256k SIMMs?
Organization: Megatest Corporation
Lines: 26
In article <1993Apr15.100452.16793@csx.cciw.ca> u009@csx.cciw.ca (G. Stewart Beal) writes:
>In article <120466@netnews.upenn.edu> jhaines@eniac.seas.upenn.edu (Jason Haines) writes:
>>
>>	I was wondering if people had any good uses for old
>>256k SIMMs.  I have a bunch of them for the Apple Mac
>>and I know lots of other people do to.  I have tried to
>>sell them but have gotten NO interest.
>>
>>	So, if you have an inovative use (or want to buy
>>some SIMMs  8-) ), I would be very interested in hearing
>>about it.
>>
>One of the guys at work takes 20 of them, uses cyano-acrylate glue to make
>five four-wide "panels" then constructs a box, with bottom, to use as a
>pencil holder.
>
Or, if you've got some entreprenuerial (sp?) spirit, get a cheapy
clear plastic box, mount the simm inside, and sell it as a 'Pet SIMM'!
I'm sure there are *plenty* of suckers out there who would go
for it!
aaron
From: vanderby@mprgate.mpr.ca (David Vanderbyl)
Subject: Re: A question about 120VAC outlet wiring..
Keywords: outlet
Nntp-Posting-Host: chip
Reply-To: vanderby@mprgate.mpr.ca (David Vanderbyl)
Organization: MPR Teltech Ltd.
Lines: 16
olsen@vetmed.cvm.uiuc.edu (Aart_Olsen) writes:
>>|> I noticed at the fusebox that some circuits have the
>>|> 12/2 with ground, and that on these circuits, the ground
>>|> wire was tied to the same bus as the neutral (white) wire.
>>
>>This is contrary to the electrical code and should be fixed.
>>
>Sorry, but this is exactly according to the NEC.
No need to be sorry, I blew it on this one.  At the main breaker box
where there is a thick wire ground leading to the earth, both neutral
and ground are hooked to this bus.  In any other breaker box (or an
outlet box, etc.) the ground and neutral must not be connected together.
From: vanderby@mprgate.mpr.ca (David Vanderbyl)
Subject: Re: mysterious TV problem -- source?
Nntp-Posting-Host: chip
Reply-To: vanderby@mprgate.mpr.ca (David Vanderbyl)
Organization: MPR Teltech Ltd.
Lines: 30
LLBGB@utxdp.dp.utexas.edu writes:
>Initial symptoms:
>-no picture or sound
>-CRT filament does NOT glow
>-flyback ticking as described abovew
>Discovered when hooked up the scope:
>-IF strip is not putting out audio or video signals
>-everything is making simple 20-30 Hz pulses
>-horiz out transistor collector (case of the TO-3) is a 20-30 Hz downgoing
>  sawtooth with ca. 15kHz ring at front end
>guys, WHAT"S GOING ON HERE?  Anyone seen this before?
What is happening is this:
1) You turn the TV on.
2) The horizontal output begins normal operation.  This powers up the
high voltage and most of the rest of the circuitry.
3) A problem is sensed and the horizontal oscillator shuts down.
4) After it powers down the cycle repeats.
Things to check:
First check for a shorted high power component.  Your best bet is the vertical
output transistor(s) or, if there is one, the voltage regulator.  The most
common cause of this type of failure is too much current being drawn
somewhere.
Also look for shutdown circuits (which your TV may or may not have),
if you can find one that is shutting down the horizontal oscillator
then it shouldn't be too hard to find the problem from there.
From: alung@megatest.com (Aaron Lung)
Subject: Re: What are some good Suppliers of Chips?
Organization: Megatest Corporation
Lines: 44
In article <1qihcl$9ri@usenet.INS.CWRU.Edu> ae454@cleveland.Freenet.Edu (Paul Simundza) writes:
>
>
>anyone know of any good supplier's of chips, one that could have almost
>any chip i need? I don't want to hunt down all the chips I may need so
>it would be greatly appreciated if anyone knows of a good distributor
>..
>thankyou
>
Paul,
Unfortunately, there are not too many retail outlets that'll stock
just about every chip made.  The stuff they will stock are the ones
that'll sell, like standard DRAM's, 80386's, 68000's, etc,etc.
i.e.  I cna't think of any 'one-stop-shopping' store.
The closest you can get is to pick up a copy of Byte magazine or
the Circuit Cellar, Popular Electronics, and the like and flip
through them.
Distributors like Wyle Electronics, Hamilton Avnet, Pioneer Electronics,
etc, etc, don't normally deal with end-users like ourselves where
we only a couple of everything...they only deal with people who buy
by the hundreds or more.  Each distributor represents and sells a variety of
different non-competing manufacturers.  What do I mean by this?
Suppose ABC Electronics sells Intel 80386's.  It's a pretty good
bet that they won't be selling any of AMD's 386's, or vice-versa.
They also can obtain just about *any* chip you want from a manufacturer
they represent.
Who knows?  You might be lucky to be able to buy from one of them.
But I'd be suprised if you do.  ALso bear in mind that the 1 or 2
qty prices they will charge you will be *much* greater than what
a mail order outlet will charge.
My advice?  If you're gonna be designing anything, try to stick
with off-the-shelf stuff.  You're going to get stuck if you use
too many esoteric parts sooner or later.
good luck,
aaron
From: adler@netcom.com (Bruce Adler)
Subject: Re: IBM-PC XT switch settings
Organization: Netcom Online Communications Services (408-241-9760 login: guest)
Lines: 26
In article <1qk158$kcp@bigbird.hri.com> obrien@bigbird.hri.com writes:
>I just got an IBM-PC XT with no documents. Its a true
>IBM, and I was wondering if anyone had the definitions
>of the 2 8 position dip switches?
SW8,SW7	number of 5.25" drives
0,0	1 drive
0,1	2 drives
1,0	3 drives
1,1	4 drives
SW6,SW5	type of display
0,0	reserved
0,1	40x25 color (mono mode)
1,0	80x25 color (mono mode)
1,1	mono 80x25
SW4,SW3	amount of memory on system board
64k chips	256k chips
0,0	64k		256k
0,1	128k		512k
1,0	192k		576k
1,1	256k		640k
SW2	co-processor installed
SW1	loop on POST
From: tsp@ccd.harris.com (Timothy S. Pillsbury)
Subject: need ACS tutorial and/or netlist examples
Originator: tsp@sp1
Keywords: ACS,SPICE,simulation
Organization: Harris Controls
Lines: 18
I recently ftp'd Al's Circuit Simulator (ACS) and I'm looking for
the tutorial which is mentioned in the Users Manual (but not found there).
I don't have any experience constructing a netlist (such as for SPICE)
and I need a little help.
The examples which come with ACS aren't explanatory about the translation
between schematic and netlist. Does anyone have the fabled "Tutorial"
or any other reference which could help me in constructing a netlist from
a schematic diagram?
(I also emailed Al himself but received no response yet. He's probably
busy with his next release.)
--
-------------------------------------------------------------------------------
Tim Pillsbury          Internet:  tsp@ccd.harris.com
uunet:  uunet!ccd.harris.com!timothy.pillsbury
-------------------------------------------------------------------------------
From: surfer@world.std.com (Internet Surfer)
Subject: New mailserver...soon...utopia-service
Organization: Boston Computer Society / ISIG
Lines: 9
For all those who are interested and would like to discuss the popular
Secret Life..and/or other technical documentaries.. Please email me
as i am starting a newsgroup
--
jolt@gnu.ai.mit.edu	      |    Its not impossible, just improbable
johnp@pro.angmar.uucp         |            (Zaphod Beeblbrox)
bl298@cleveland.freenet.edu   |   N1NIG@amsat.org (Being a Ham is so grand)
From: ardai@wizard.atb.teradyne.com (Michael Ardai)
Subject: Re: Source for carbide pc board drills?
Organization: Teradyne, Inc. Boston MA
Lines: 18
In article <C5EJL7.LIn@news2.cis.umn.edu> Mike Diack <mike-d@staff.tc.umn.edu> writes:
-In article <C5DGG7.5ox@wang.com> , pvr@wang.com writes:
->   Who sells the special carbide drills used to drill pc boards?
->I am looking for sizes smaller than #60, #65 or #70 would be good.
-best deal i ever saw on carbides was at ELI electronics - Cambridge
-Mass. Quite close to MIT, #70 drills @ $5.00 for a box of 50. ELI are
-in the Boston fone book.
Actually, I think they are all #57.  Their phone number is 617 547 5005
and I will probably have some over at the MIT Flea this Sunday.
/mike
--
\|/     Michael L. Ardai     N1IST             Teradyne ATG Boston
--- -------------------------------------------------------------------------
/|\                    ardai@maven.dnet.teradyne.com
From: cph@dmu.ac.uk (Chris Hand)
Subject: Cheap LCD panels & seeking info
Organization: De Montfort University, Leicester, UK.
Lines: 37
Attention hardware hackers and bargain seekers!
I just bought a 640x200 pixel LCD panel for 25 UK pounds.  I have
a datasheet for a similar panel, but I'm looking for proper data.
If anyone can help with locating data for this device (before I start
with the routine on the phone to Hitachi and rummaging through the
library), then I'll pass on the source.
Type: LM225 (Hitachi)
Resolution: 640W x 200H (so can do 80x25 chars on 8x8 matrix)
Bought from:
Greenweld Electronics Ltd
27 Park Rd
Southampton SO1 3TB, UK
Tel. +44 703 23 63 63
Fax. +44 703 23 63 07
Email: Compuserve [100014,1463]
NB: I only just bought this!  I don't even know if it works!
Price was 25 UK pounds including VAT (17.5%), which isn't
payable if you're outside the EC.
Thanks for any info!
Chris
--
Chris Hand, Lecturer                Internet mail: cph@dmu.ac.uk
Dept of Computing Science,          Voice: +44 533 551551 x8476
De Montfort University, The Gateway,  Fax: +44 533 541891  FIDOnet: 2:440/32.50
LEICESTER, UK   LE1 9BH             >> Linux: *free* unix for IBM PCs! <<
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Subject: Re: R/S Battery of the Month Club
Organization: NASA Langley Research Center and Reptile Farm
Lines: 9
NNTP-Posting-Host: grissom.larc.nasa.gov
In article <JWATERMA.93Apr14214858@jade.tufts.edu> jwaterma@jade.tufts.edu (Jason Waterman) writes:
>I talked to a friend who works for Radio Shack, and he said the deal
>with the Red Batteries were that they had too much lead in them.
>Condidering the Red Batteries had a life cycle shorter than a mayflies,
>I think the EPA was worried about all those batteries being dumped out.
Pardon me, but why would carbon-zinc cells have any lead in them at all.
--scott
From: tomb@hplsla.hp.com (Tom Bruhns)
Subject: Re: Do Analog Systems Need Ground Planes?
Organization: HP Lake Stevens, WA
Lines: 25
engp2254@nusunix1.nus.sg (SOH KAM YUNG) writes:
>I understand the need for a ground plane in a digital system. However, I
>would like to know if such a ground plane is also necessary in an analog
>system.
>
>(Note: this ground plane will not be connected, except at one point, to
>the signal ground).
>
>I keep getting conflicting answers over this. Does having a ground plane
>in an analog system help reduce noise also? My system only deals with
>low frequency signals (up to 100Hz only!!!).
Well, one reason for getting conflicting answers is that it depends on
what you want the ground plane to do.  A continuous conductor is a good
electrostatic shield.  Do you have signals on your board that need
shielding rom other things?  This shielding won't do much good for magnetic
fields, unless you make it continuous around the circuit to be shielded,
like a Faraday cage.
The flip side of the coin:  if you are working with (very) high impedances,
you could end up with capacitances to the gound plane that cause problems.
You aren't likely to encounter this at 100Hz, but at 20kHz, it can be a
real problem (one that bit me once).
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Subject: Re: what to do with old 256k SIMMs?
Organization: NASA Langley Research Center and Reptile Farm
Lines: 12
NNTP-Posting-Host: grissom.larc.nasa.gov
In article <C5JCH1.FrC@ulowell.ulowell.edu> wex@cs.ulowell.edu writes:
>In article <1993Apr15.100452.16793@csx.cciw.ca>, u009@csx.cciw.ca (G. Stewart Beal) writes:
>|> >	I was wondering if people had any good uses for old
>|> >256k SIMMs.  I have a bunch of them for the Apple Mac
>|> >and I know lots of other people do to.  I have tried to
>|> >sell them but have gotten NO interest.
>
>We use them as Christmas tree decorations, the cat doesn't eat these.
Yes, but they don't look appropriate.  I much prefer used 833 tubes on
my tree.
--scott
From: davidj@rahul.net (David Josephson)
Subject: Re: MICROPHONE PRE-AMP/LOW NOISE/PHANTOM POWERED
Nntp-Posting-Host: bolero
Organization: a2i network
Lines: 26
In <C5JJJ2.1tF@cmcl2.nyu.edu> ali@cns.nyu.edu (Alan Macaluso) writes:
>I'm looking to build a microphone preamp that has very good low-noise characteristics,  large clean gain, and incorportates phantom power (20-48 volts (dc)) for a PZM microphone.  I'm leaning towards a good, low-cost (??) instrumentation amplifier to maintain the balanced input from the microphone, for its good CMRR, internal compensation, and because i can use a minimal # of parts.
>Does anyone out there have any experience, suggestions, advice, etc...that they'd like to pass on, I'd greatly appreciate it.
>---
>A l a n  M a c a l u s o		 	PURPLE MOON GIANTS
>ali@cns.nyu.edu  				158 E. 7th. St. #B5
>(212) 998-7837					NYC  10009
>						(212) 982-6630
>
Without doing anything really tricky, the best I've seen is the
Burr-Brown INA103. Their databook shows a good application of this
chip as a phantom power mic pre.
>
--
------------------------------------------------------------------------
Josephson Engineering, San Jose California      MICROPHONES
Tel/ 408-238-6062  Fax/ 408-238-6022            INSTRUMENTATION
email:david@josephson.com  ftp info from: rahul.net /pub/davidj/
From: ray@ole.cdac.com (Ray Berry)
Subject: Re: $25 network
Organization: Cascade Design Automation
Lines: 11
zjoc01@hou.amoco.com (Jack O. Coats) writes:
>The same folks now have out LBL (Little Big Lan) for $75.  I think you
>get it for $50 if you already own $25 Network.  LBL works with Arcnet,
>parallel ports, and serial ports in any combination for up to 250 or so
>nodes.
LBL now offers ethernet support also, although presently it is limited
to NE1000/NE2000 style boards.  LBL owners can get an update for $8.50.
--
Ray Berry kb7ht ray@ole.cdac.com  rjberry@eskimo.com  73407.3152@compuserve.com
From: betts@netcom.com (Jonathan Betts)
Subject: Where to find CHEAP LCD displays?
Organization: Netcom Online Communications Services (408-241-9760 login: guest)
Lines: 32
Sci.E(E) netters:
I am setting out to build and market a small electronic device that
requires an LCD display.  All of the analog electronics are working
fine, I have ordered a PIC ICE (not vice versa) since the PICs are so
cheap and low-power, but I am having a devil of a time finding any
LCD displays in the 6-8 digit range that are priced as low as I need.  I
am looking for somthing in the range of $1 in quantities of about
1000-10,000.
Mainstream distributors like Almac cannot help me without a part
number, or when they do look around for something in their line
they find a $15 8-digit LCD.  Even Digikey's cheapest offering is $5 in
quantity.
I know LCD displays like this must exist because I see whole
calculators for sale for $4.99, meaning the retailer probably buys it
for $3.50 and the wholesaler probably gets it for $2.50 or so.  This
$2.50 includes assembly labor, packaging, sales, transportation,
import duties, the case and keyboard, the PC Board, the processor
chip, the solar cell --- and the LCD.  The LCD can't cost much.
If anyone could put me in touch with some manufacturers and/or
distributors that handle such things I would be much obliged.
-Joe Betts
betts@netcom.com
P.S.  I have tried tearing apart several cheap consumer devices that
have LCDs only to find that the LCDs are unlabelled.  Has anyone else
had better luck with this strategy?
From: morrow@cns.ucalgary.ca (Bill Morrow)
Subject: Amplifier into CD-ROM earphone plug ?
Nntp-Posting-Host: cns16.cns.ucalgary.ca
Organization: University of Calgary
Lines: 16
We have a Sun CD-ROM drive which I would like to play audio CD's in.
I have an old 10 watt amplifier which works fine when connected to a
junk "Walkman" style AM/FM radio. This amp ties the common path of the
earphone connection to ground.
However, it doesn't work with my Sony Walkman cassette player, or the CD drive,
it produces of loud low-frequency tone. Obviously Sony doesn't ground
the earphone output common. Does anyone have specs on the CD drive's
output? Will an audio transformer help? What are others using to
play there CD's in the Sun drive so that more than one can listen?
Thanks for the help.
--
Bill Morrow    Clinical Neurosciences, University of Calgary
e-mail: morrow@cns.ucalgary.ca voice: (403) 220-6275 fax: (403) 283-8770
3330 Hospital Drive NW Calgary, Alberta, CANADA T2N 4N1
From: oxenreid@chaos.cs.umn.edu ()
Subject: Re: Radar detector DETECTORS?
Nntp-Posting-Host: chaos.cs.umn.edu
Organization: University of Minnesota
Lines: 23
In <1993Apr06.173031.9793@vdoe386.vak12ed.edu> ragee@vdoe386.vak12ed.edu (Randy Agee) writes:
>So, the questions are -
>  What do the radar detector detectors actually detect?
>  Would additional shielding/grounding/bypassing shield stray RF generated by
>  a radar detector, or is the RF actually being emitted by the detector
>  antenna?
>  Are any brands "quieter" than others?
Ok, so your a HAM.   Well, tune in 10.7Mhz or 455Khz.  These numbers sound
like some you have herd before?   Thats right, you guessed it, they are
common IF numbers.   Every Super-Het receiver has a local oscillator(s)
which generates an IF.  This is what your detector detector is detecting (the
local oscillator).
Some of these have two or more local oscillator which generate more ways to
receiver you.  If you want to receiver something at say 10.525Ghz you must
generate a local oscillator signal of 10.525Ghz - 10.7Mhz = your local osc
frequency.  This 10.7Mhz IF is then fed into a normal AGC ckt.
The detector is keyed uppon the AGC voltage (your mileage may vary).  Since
the AGC is a negative feed back device, a positive voltage sets off a ...
I think you get the picture.
From: kennehra@logic.camp.clarkson.edu (Rich"TheMan"Kennehan)
Subject: subliminal message flashing on TV
Organization: Clarkson University
Lines: 11
Nntp-Posting-Host: logic.clarkson.edu
X-Newsreader: TIN [version 1.1 PL8]
Hi.  I was doing research on subliminal suggestion for a psychology
paper, and I read that one researcher flashed hidden messages on the
TV screen at 1/200ths of a second.  Is that possible?  I thought the
maximum rate the TV was even capable of displaying images was 1/30th
of a second.  (or 1/60th of a second for an image composed of only odd
or even scan lines)
- Rich
kennehra@logic.camp.clarkson.edu
From: urbina@novax.llnl.gov
Subject: Telcom wiring question...need help
Organization: Lawrence Livermore National Laboratory, NCD
Lines: 26
NNTP-Posting-Host: novax.llnl.gov
I've got two lines coming into my apartment. Two different telephone numbers.
When I ordered the second line installed, instead of bringing out another 4
wire bundle, the telco just connected up to my yellow and black wires. So I
have one line on red & green and the other on yellow & black.
Today I was monitoring the voltage on both lines. I had a voltmeter across
the red and green and read back 52 volts. I then lifted up the receiver on my
second line.(black & yellow wires) The voltage dropped to 31 volts on the first
line. (red & green wires) I repeated this experiment with the second
line(monitoring black & yellow and lifting the handset off the cradle on the
red and green line.) It also dropped to 31 volts.
Why is this ? I thought these were separate lines.
Next I went to the 66 block and disconnected the blue and white lines coming in
from the telco cable. I then disconnected all the phones in my apartment and
went back to the 66 block and did some resistance measurements. Both lines read
open.
I'll appreciate any help on this. Is this considered normal ?
Guy Urbina
Urbina@novax.llnl.gov
From: mwtilden@math.uwaterloo.ca (Mark W. Tilden)
Subject: BEAM Robot Olympic Games next Week in Toronto.
Organization: University of Waterloo
Lines: 17
One week to the Robot Olympic games.  Fire up the mechanoids for combat
and come on down.
Competitors please note that there has been a slight change; the registration
desk will now be in the forward building of the Science Centre rather than
in the main competing hall.  When you arrive, please go to this desk.  Those
that have pre-registered by real-mail will find badges waiting.
Is all.  See you here.
--
Mark Tilden: _-_-_-__--__--_      /(glitch!)  M.F.C.F Hardware Design Lab.
-_-___       |              \  /\/            U of Waterloo. Ont. Can, N2L-3G1
|__-_-_-|               \/               (519)885-1211 ext. 2454
"MY OPINIONS, YOU HEAR!? MINE! MINE! MINE! MINE! MINE! AH HAHAHAHAHAHAHAHAHA!!"
From: klg@mookie.mc.duke.edu (Kim Greer)
Subject: Re: electronic odometers (was: Used BMW Question ..... ???)
Organization: Duke Medical Center - Radiology
Lines: 27
Nntp-Posting-Host: mookie.mc.duke.edu
In article <1993Apr15.044636.29924@slcs.slb.com> dcd@se.houston.geoquest.slb.com (Dan Day) writes:
>That's scary -- if there's a way to set an arbitrary mileage figure
>into the odometer, you can't trust *any* odometer reading, even
>if you can prove that the odometer itself is the same one that
>came on the car originally.
I was wondering if anyone can shed any light on just how it is that these
electronic odometers remember the total elapsed mileage?  What kind of
memory is stable/reliable enough, non-volatile enough and independent enough
(of outside battery power) to last say, 10 years or more, in the life of a
vehicle?  I'm amazed that anything like this could be expected to work for
this length of time (especially in light of all the gizmos I work with that
are doing good to work for 2 months without breaking down somehow).
Side question:  how about the legal ramifications of selling a used car with
a replaced odometer that starts over at 0 miles, after say 100/200/300K
actual miles.  Looks like fraud would be fairly easy - for the price of a
new odometer, you can say it has however many miles you want to tell the
buyer it has.
Thanks for any insight.
Kim Greer
Duke University Medical Center		 klg@orion.mc.duke.edu
Div. Nuclear Medicine  POB 3949		 voice: 919-681-5894
Durham, NC 27710  		         fax: 919-681-5636
From: tod@cco.caltech.edu (Tod Edward Kurt)
Subject: data pods (10248B) for HP logic analyzer (1615A)?!?
Organization: California Institute of Technology, Pasadena
Lines: 11
NNTP-Posting-Host: sandman.caltech.edu
Keywords: logic analyzer HP
Anyone out there in netland have a spare data pod or two from an old
1615A Hewlett Packard logic analyzer?  If you do, I'd like to buy it off
of you.  The pod's part number is 10248B.
As a side note, anyone know of any good surplus dealer or other organization
that would carry wayward logic analzer pods?
Thanks a byte,
Tod
tod@cco.caltech.edu
From: mmm@cup.portal.com (Mark Robert Thorson)
Subject: Re: Exploding TV!
Organization: The Portal System (TM)
Distribution: usa
Lines: 6
Sounds like the picture tube lost vacuum.  This would cause the filament
to ignite and could actually turn the tube from a vacuum to a pressure
vessel, followed by an explosion when the neck assembly (mostly likely
cracked to begin with) blows off.  During the whole sequence of events,
the other circuits may continue functioning, which accounts for not
losing sound.
From: fmg@alpha.smi.med.pitt.edu (Filip Gieszczykiewicz)
Subject: Scope questions
Summary: What is [a] "Storage scope"
Distribution: na
Organization: Medical Informatics, Pittsburgh, PA USA
Lines: 33
Greetings. I've been seeing the word "storage" mentioned
around oscilliscopes but I'm curious, what does it mean?
If my life depended on it, I'd say that it's a scope that
uses long-persistance phosphor to keep the successive
taces on the screen for some unit of time - "store" them.
Do I get to live?
Also, I've been shopping for a decent, used, [old] scope
since my Tek 514A (portable...NOT!) and my Heathkit O-1000
are all single trace and I need more... like 2 or 3 and at
least 50MHz (maybe 100...)
During my shopping at hamfests etc. I've run into the
problem of "old scope" terminology. I can imagine what
a "mainframe" and "plug-in" are but some things like
the above "storage", "coax input" (Hey, where do I get a
probe that fits this? I had to fiddle with mine for a week
before I got anything resembling "a good trace" - they all
come with BNC connectors!), "unblanking" (huh?), and, oh,
just like my 514 manuals, MANY changes were made along the
way to the schematic - scopes, even with IDENTICAL model
numbers, have different (better?) response/performance than
others - how can I pick the better one? Does the rule of the
higher SN the better apply?
Take care.
--
/ Filip "I'll buy a vowel" Gieszczykiewicz. | Best e-mail "fmgst+@pitt.edu"  \
| All ideas are mine but they can be yours for only $0.99 so respond NOW!!!! |
| I live for my EE major, winsurfing, programming, SCA, and assorted dreams. |
\ 200MB Drive - Linux has 100MB and MS-DOS has 100MB. MS-DOS is worried ;-)  /
From: s5600043@nickel.laurentian.ca
Subject: Re: CD player going wonky - advise needed !
Lines: 18
Organization: Laurentian University
In article <1993Apr13.150525.17978@nessie.mcc.ac.uk>, sl@nessie.mcc.ac.uk (Stuart Lea) writes:
> Hello,
> 	I've got a problem with my CD player (SONY CDP-35) in that it refuses
> to play discs - more than a minor inconvenience!  The player itself doesn't
> recognise that there is a disc in.  It's an intermitant problem, but one
> that is becoming more frequent.
>
> 	Is this a common problem with older CD players and, if so, what
> can be done to rectify it ?  If there is no obvious answer, how can I begin to
> start fault finding.  To start off with, How does thet mach recognise that
> there is a disc in in the first place ?
My experience is that the CD drawer becomes a bit loose, and the CD either skips
or can't be read.  Try seeing if all the screws that hold down the drawer
assembly are tightened properly.  Other than that, my next guess would be one of
the motors.  Hope this helps.
Dave Haans, Laurentian University, Sudbury, Ontario.
From: rogerw@world.std.com (Roger A Williams)
Subject: Re: Adcom cheap products?
Organization: The World Public Access UNIX, Brookline, MA
Lines: 27
mdonahue@amiganet.chi.il.us (Mike Donahue) writes:
>I do NOT know much about Adcom Mobil Audio products, but I DO know for a fact
>that ADCOM does NOT make its own "High End" Home Audio Equptment and that 80%+
>of it comes directly out of Tiawan...
Like most high-volume manufacturers, Adcom has most of its PC boards
assembled off-shore (in their case, mostly in the far east).  Final
assembly _and testing_ are done in East Brunswick.
The products are, and have always been, designed entirely in the US;
by their own staff and by audiophile gurus like Walter Jung.  Adcom
also tends to prefer American and European components over their
Japanese/Far East equivalents.
Off-shore assembly is one reason that Adcom is able to make products
that perform as well as those from people like Audio Research and Van
Alstine (and better than Hafler and Forte'), but at a much lower cost.
Of course, if your musical diet consists mostly of Rock, you might
prefer components from Kenwood or Pioneer...
Roger Williams		| "Most great discoveries are made
rogerw@world.std.com	|  by accident: the larger the
consulting engineer	|  funding, the longer it takes to
Middleborough, Mass.	|  have that accident."
From: alung@megatest.com (Aaron Lung)
Subject: Re: Telephone on hook/off hok ok circuit
Organization: Megatest Corporation
Lines: 59
In article <1993Apr15.144826.4607@bnr.ca> moffatt@bnr.ca (John Thomson) writes:
>: >> >Just a thought of mine here:
>: >> >Since an on-hook line is aprox 48-50V, and off-hook it usually drops below 1
>: >> >How about an LED in series with a zener say around 30V.
>: >> >On-hook = LED on
>: >> >Off-hook = LED off.
>: >> >Would this work? If anyone tries/tried it, please let me know.
>: >>
>: >> Aye, there's the rub -- if you draw enough current to light an LED, the
>: >> equipment at the phone company will think you've gone off hook.
>: >> In the on-hook state you're not supposed to draw current.
>: >
>: >Which means you should just use your Digital VoltMeter. You can use an
>: >old VOM but the phone company equipment can detect that and might think
>: >there's something wrong with the cable.
>: >
>:
>: Look Guys, what's the problem here?  If you want a light that goes on when
>: the 'phone is *Off* hook, all you need it to run it in *series* with the
>: line, as I mentioned in my previous post.  If you want a light that goes on
>: when the 'phone is *on* hook, all you need is a voltage threshold detector.
>
>If you're going to do the series Diode thing (which is the easiest), just
>make sure that the LED can take the current (I can't recall it off-hand, but
>it's something like 100mA or more?)
Careful now folks... Also consider the 90VAC+ @20Hz that is forced on ring
and tip when the phone's supposed to ring!  Even with a simple zener
and LED setup, you might end up with some carbon real quick.  Whatever
scheme you use, make sure you've got at least 200V-rated components on
the frontend.
Also remember that, if I'm not mistaken, the phone line is a 600ohm
equivalent circuit.  Any current you draw from the 48V or so gets
dropped across that 600ohms.  That's fine until you're down to roughly
12V, when Ma Bell considers it to be off-hook.  But dropping it that
far down is probably a big no-no.
The easiest implementation to accomplish the above??
tip  ------->|-----\/\/\/\-----+----------+
rectifier  resistor  |          |
diode                |          \
V          /
zener  /---/        \  resistor
|          /
|          |
|          V   LED
|         ---
|          |
ring --------------------------+----------+
This is only a suggestion...go ahead and blow holes in it, but you
get the idea.  Choose a high-efficiency LED so you don't need much
current to get it to light up.  Choose values for the other components
as required.
aaron
From: alung@megatest.com (Aaron Lung)
Subject: Re: Uninterruptible Power Supply
Organization: Megatest Corporation
Lines: 40
In article <1qk724INN474@hp-col.col.hp.com> cab@col.hp.com (Chris Best) writes:
>I'm no expert at UPS's, but you said something that made it sound like
>you didn't realize something.  On a typical UPS (well, on ours, anyway),
>there is NO switchover from AC to DC.  All the protected equipment is
>ALWAYS running from the batteries (via an inverter), with the usual
>condition of also having them on charge.  If the power fails, big deal -
>the computers never see it (until the batteries start to droop, but
>there's something like 60 car-sized batteries in that cabinet, so it
>takes a while).
>
>If you were gonna run the guts on straight DC instead of an inverter,
>why not do it all the time?  Then there'd be no switchover to screw
>things up, and no having to sense the failure fast.  Just keep the DC
>on charge when the power is on, and it'll be there in zero time when
>you "need" it.
>
Actually, it's a bit more complicated than that...I sounds to me,
your UPS takes in AC, rectifies it to DC to charge the batteries, and
then takes the battery DC and chops it to AC again, feeding your
equipment.  This approach is the easiest and cleanest way to
switchover from the mains to battery once your power kicks out since,
as you mentioned, nothing will know about what happened down the line.
Another way to do the UPS scheme is to use the mains until you
lose power, and then kick in the battery backup with it's inverter to
replace the lost power.  The problem here is the switchover time and
you've got to resync the AC in no time flat.
Unfortunately, most everything is built around the assumption that
AC is available, so the UPS guys have to provide and AC output to
be usable...ya sorta have to make it work with what there already.
Similar story with our telephone system.  It was first invented back
in the 1800's.  We're still using the same damn system (media) as they
did back then.  If I have a phone from back then, I can assure you
it'll work on today's phone system.  It costs too much to overhaul
everyone to a new system, so they make it work with what is out there.
.
From: alung@megatest.com (Aaron Lung)
Subject: Re: Exploding TV!
Organization: Megatest Corporation
Distribution: usa
Lines: 39
In article <1qk4hj$qos@vtserf.cc.vt.edu> prasad@vtaix.cc.vt.edu (Prasad Ramakrishna) writes:
>I had a GE Emerson 13" color TV for about 3 years and one fine day,
>while we were watching something (I doubt if the program was the cause),
>we heard a mild explosion.   Our screen went blank but there was sound,
>so we thought, 'oh we have special effects on the program'.  But soon
>the sound stopped and smoke started to appear at the back of the TV.
>The brilliant EEs we are, we unplugged the TV and called customer service
>only to be thrown around by please hold, I will transfer u to blah blah..
>  Finally we abandoned the idea of trying to fix the TV and got a new one
>(we wanted a bigger one too!).
> After all the story, what I wanted to know is: Is my problem an isolated
>incident or a common one? (I recall reading about Russian TVs exploding, but
>not here, in the US). Why would the picture tube explode or even smoke?
> I still have the left over TV set, I might dig into it this summer. Any
>idea where I can get parts for these things? (probably will cost more than TV).
>
Heh, heh, heh, heh....I laugh because I have the same damn TV, and it
did the same thing!  Actually it is a Goldstar, but it's essentially the
same TV and electronics--just a different face plate and name.
#1.  Fortunately, TV tubes don't explode.  I'd think the TV mfrs want
to make this possibility remote as possible.  If at all, they'll
*implode* and the glass that blows out would be the result of the
glass boucing off the back of the tube due to the implosion. In any
case, don't kick it around! :-)
#2  I fixed the TV after getting a hold of some schematics.  It turned
out to be a blown 2W resistor feeding the flyback transformer.  I guess
the original resistor was a bit too small to dissipate the heat it
created, burning itself out.  I checked to make sure the flyback wasn't
shorted or anything first!  Oh, luckily, I had a resistor handy lying
around that had just the right value for what I needed.  I can't see it
being more than 50 cents!.
Well, needless to say, the TV still works today.  So go get a set of
schematics and have some fun...just don't get shocked poking around
the flyback.
Organization: Queen's University at Kingston
From: <LEEK@QUCDN.QueensU.CA>
Subject: Re: ADC card for computer
Distribution: world
Lines: 54
In article <1qi8e3$b5e@lll-winken.llnl.gov>, you say:
>
>I would like to digitize the output of a SQUID magnetometer (range -10 V
>to +10 V) and do digital signal processing in a computer, say a Macintosh
>II or a 486 PC.  I would like a good 16 bit ADC with good linearity and a
>high conversion speed, at least 50 kHz, preferably 200 kHz.  Other concerns
>
>(2)  Must I use an ADC external to my computer to avoid digital noise
>     feedback into my sensitive SQUID electronics?
Might be a good idea...  The resolution you requested is about 0.3mV
In order to get what you've paid for, noise level better be lower than
that.  It is kind of hard to do it in a noisy box like you can expect
inside a PC.
Before you pay $$$ for a PC card, test it out by sampling a low
distortion sine wave (I think there is a sine wave on a CD.  Digital
Domain ?  There are possibly other low THD sources)  Run the digitized
waveform through a FFT transform and take alook at the noise floor on
the spectrum.  That's should give you a good indication of the design.
(That's what I am doing to test a data acquistion system I have designed
- I got the idea from MAXIM data sheet.)
If you can live with 14 bit resolution, I would recommend looking at
the MAX121 from MAXIM.  It is a high speed (308KHz) complete
sampling A/D with DSP interface.  The input range is +/- 5V and it
uses a serial interface (which can easily be optically isolated
from the computer to elinimate a major noise source)  The Analog design
guide I got from them shows a -100db noise level.  They claim a -77db
max (-85 typ.) THD.  Looks pretty good for the $12 @ 1000 pieces
A evaluation kit is available.  Might want to give these nice folks a
call.  1-800-998-8800 or fax: (408)737-7194 and (408) 737-7600 ext4000
for application assistance.
This assumes that you can build your own DAS and write your own software.
(Hey you can get the MAX121 as a free sample just by calling the 1-800 #)
>I would appreciate discussion of your personal experience with a Mac or PC-
>based ADC system.
I would recommend you to find out the resolution that can be gotten out
of your system by looking at the noise level, otherwise you might be
throwing out your money.
>Charles Cunningham
>cec@imager.llnl.gov
K. C. Lee
Elec. Eng. Grad. Student
I have no connection with MAXIM except I do in general recommend
companies that give samples to students to others.  I feel they
deserve that for being nice to me.
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: what to do with old 256k SIMMs?
Organization: Macquarie University
Lines: 14
Distribution: world
NNTP-Posting-Host: macadam.mpce.mq.edu.au
In article <120466@netnews.upenn.edu>, jhaines@eniac.seas.upenn.edu (Jason Haines) writes:
|>
|> 	I was wondering if people had any good uses for old
|> 256k SIMMs.  I have a bunch of them for the Apple Mac
|> and I know lots of other people do to.  I have tried to
|> sell them but have gotten NO interest.
|>
|> 	So, if you have an inovative use (or want to buy
|> some SIMMs  8-) ), I would be very interested in hearing
|> about it.
The most practical use I've seen for them is as key ring ornaments :-)
JohnH
From: sknapp@iastate.edu (Steven M. Knapp)
Subject: Re: Radar detector DETECTORS?
Organization: Iowa State University, Ames, IA
Lines: 16
In article <oxenreid.734127163@chaos.cs.umn.edu> oxenreid@chaos.cs.umn.edu () writes:
>In <1993Apr06.173031.9793@vdoe386.vak12ed.edu> ragee@vdoe386.vak12ed.edu (Randy Agee) writes:
>
>>So, the questions are -
>>  Are any brands "quieter" than others?
Yes some radar detectors are less detectable by radar detector
detectors. ;-)
Look in Car and Driver (last 6 months should do), they had a big
review of the "better" detectors, and stealth was a factor.
________________________________________________________________________
Steven M. Knapp                             Computer Engineering Student
sknapp@iastate.edu                  President Cyclone Amateur Radio Club
Iowa State University; Ames, IA; USA      Durham Center Operations Staff
From: cgordon@vpnet.chi.il.us (gordon hlavenka)
Subject: Re: making copy of a Video tape
Keywords: video
Organization: Vpnet Public Access
Lines: 19
>There are devices you can buy and/or make.  Look in Radio & Popular
>Electronics mags for the devices.  If all else fails, you can build one
>using the curcuit design from the Dec. '87 issue of Radio Electronics.
My very favorite ad for such a device is on the back of the latest
Damark catalog.  Quoting from memory:
[Big flashy type]
"Dual deck VCR copies any tape -- Even those that are copy protected!*"
(And underneath the ad in very small print: *This device is not intended
for making illegal copies of copyrighted material.)
:-)
--
----------------------------------------------------
Gordon S. Hlavenka           cgordon@vpnet.chi.il.us
Vote straight ticket Procrastination party Dec. 3rd!
From: russotto@eng.umd.edu (Matthew T. Russotto)
Subject: Re: electronic odometers (was: Used BMW Question ..... ???)
Organization: Project GLUE, University of Maryland, College Park
Lines: 33
NNTP-Posting-Host: tea.eng.umd.edu
In article <1993Apr14.174857.28314@porthos.cc.bellcore.com> dje@bmw535.NoSubdomain.NoDomain (Don Eilenberger) writes:
}In article <1993Apr14.153740.18542@nimbus.com>, jimiii@nimbus.com (Jim Warford) writes:
}|>  There are two simple procedures for alterating any odometer.
}|>
}|> 1. Mechanical driven odometer:
}|>     Remove the speedo cable from the transmission.
}|>     Attach a drill and run at max speed until the speedo turns over.
}|>     Continue until the desired mileage is reached.
}|>
}|> 2. Electronically driven odometer:
}|>     Remove the sensor wire from the sensor.
}|>     Attach the Calibration out signal from an Oscope to the wire.
}|>     Run until the speedo turns over and attains the desired mileage.
}
}Dear Faster.. I kinda wonder.. have you ever tried version 2? On what?
}Since the sensor wire on a BMW feeds also into the computer.. and we
}don't know what signal voltage is expected from it.. bad things
}*could* happen... also since we don't know the pulse rate, we
}may damage the analog part of the speedo (yes.. BMW uses a combined
}instrument.. speed in analog, trip and total milage is digital) with
}the needle pegged up against the 160MPH stop..
}
}Just a thought...
You've got the oscilliscope, so you connect it up to the sensor wire
and measure this stuff.  That way you know what it expects.
--
Matthew T. Russotto	russotto@eng.umd.edu	russotto@wam.umd.edu
Some news readers expect "Disclaimer:" here.
Just say NO to police searches and seizures.  Make them use force.
(not responsible for bodily harm resulting from following above advice)
From: ritterbus001@wcsub.ctstateu.edu
Subject: Re: Picking up cable tv with an aerial.
Lines: 37
Nntp-Posting-Host: wcsub.ctstateu.edu
Organization: Yale University, Department of Computer Science, New Haven, CT
In article <gyJX2B2w165w@inqmind.bison.mb.ca>, dino@inqmind.bison.mb.ca (Tony stewart) writes:
> jfsenior@unix1.tcd.ie (John Senior) writes:
>
>> Recently, I discovered that it was possible to receive cable
>> tv through the telescopic aerial on the top of my tv.
>> The nearer this aerial is moved to the cable (which I am not
>> connected to) which runs under the eaves of the house the better
>> the signal.  Now, I was wondering how can I improve the signal?
>> Is it possible to improve the signal significantly? (some channels
>
> CABLE EGRESS or emanations if you will are being radiated at free space
> impedance from cables that may be harmonically realated to certain
> channels and therfore the standing waves at 1/4 wave will transfer
> efficiently. Also your antenna (a loose monopole) is also harmonically
> tuned and will be more efficient at 1/2 wavelength multiples.
>
> Your best bet for this research is to use a tuned YAGI antenna to get the
> gain you need. (Std TV roof antenna type) The dipoles should be parallel
> to the radiating cable. A pre-amp doesn't help significantly in my
> experience in most cases.
>
> dino@inqmind.bison.mb.ca
> The Inquiring Mind BBS, Winnipeg, Manitoba  204 488-1607
Wow, what a concept!  Does anybody want to speculate on how this
"non-connection" would fit into the theft of cable services laws?
It seems to me that unless this case is specifically written into
the legislation that the cable company would not have a leg to
stand upon in court.
Does anybody out there have any specific legal knowledge on this?
Jim Ritterbusch
ritterbus001@wcsu.ctstateu.edu    - or - ne22@radiomail.net  (temp, rf)
There is an art, the Guide says, or rather a knack to flying.  The
knack lies in learning how to throw yourself at the ground and miss.
From: doherty@coolpro.melpar.esys.com (Kevin Doherty)
Subject: Hard Drive Component Costs
Organization: E-Systems, Melpar Division
Lines: 17
Does anyone have some information on the relative fraction of the final
cost of each component in an average hard drive?  For instance, I'm pretty
sure the heads and the platters are the most expensive parts, with the
assembly costs running a close third.  Cost of the electronics is likely
in the noise.
Any hard numbers ($$ or percentage)?  Thanks.
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=+
| Kevin Doherty           E-Systems/Melpar Division   doherty@melpar.esys.com |
| Principal Engineer      Falls Church, VA 22046      (703) 560-5000x2659     |
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=+
--
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=+
| Kevin Doherty           E-Systems/Melpar Division   doherty@melpar.esys.com |
| Principal Engineer      Falls Church, VA 22046      (703) 560-5000x2659     |
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=+
From: victor@inqmind.bison.mb.ca (Victor Laking)
Subject: Re: Radar detector DETECTORS?
Organization: The Inquiring Mind BBS  1 204 488-1607
Lines: 30
alee@bmerh794.bnr.ca (Louis Leclerc) writes:
>
> In article <34263@oasys.dt.navy.mil> you write:
> >VA, CT, Wash DC  and I think BC Canada where I've heard they actually
> >use Radar detector detectors.
>
> Nope, not in British Columbia.  Detectors are legal here in BC, I've even
> got one.
>
> In Alberta and Ontario they're illegal, and detection devices are sometimes
> used.  I've heard the police in Ontario prefer a much more direct method of
> detection.  Just trigger the radar gun, watch for people slamming on the
> brakes, and search the car.
>
>
> David Lee
> leex@sfu.ca
>
They are illegal here in Manitoba as well though I don't know what
methods are used to detect them.
It has always amazed me with the way the laws work.  It is not illegal to
sell them here in Manitoba, only to have them within a vehicle.  (Last I
heard, they don't have to be installed to be illegal.)
victor@inqmind.bison.mb.ca
The Inquiring Mind BBS, Winnipeg, Manitoba  204 488-1607
From: mkilpela@mtu.edu (Mark E. Kilpela)
Subject: Re: A question about 120VAC outlet wiring..
Nntp-Posting-Host: techmac10.tech.mtu.edu
Organization: Michigan Technological University
Lines: 32
In article <1993Apr14.172145.27458@ecsvax.uncecs.edu>,
crisp@ecsvax.uncecs.edu (Russ Crisp) wrote:
>
> Hello
> I'm considering modernizing some old wiring in my home, and
> I need a little advice on outlet wiring.  Several outlets
> are the old 'two prong' type, without the ground.  Naturally,
> the wire feeding these outlets is 12/2, WITHOUT the ground
> wire.  I noticed at the fusebox that some circuits have the
> 12/2 with ground, and that on these circuits, the ground
> wire was tied to the same bus as the neutral (white) wire.
>
> SO..  Here's my question.  It seems to me that I'd have the
> same electrical circuit if I hooked the neutral[D[D[D[D[D[D[D[D[D[D[Da jumper from the neutral
> over to the ground screw on new 'three prong' grounding outlets.
> What's wrong with my reasoning here?
First, it will not pass a National Electrical code inspection.
Secondly, The neutral wire is current carrying and the ground wire
shouldn't be, or only during a fault condition.
The reason the neutral and ground are tied together in the panel is the
tranformer on the power pole has a grounded center-tap secondary, with the
grounded center-tap the neutral.  This gives 120v to neutral(ground) from
each side of the transformer and 240v across the transformer.  So in effect
the neutral and ground should be at the same potential.
------------------------------------------------------------------
Mark E. Kilpela              email mkilpela@mtu.edu
Michigan Technological University
School of Technology
------------------------------------------------------------------
From: swalker@uts.EDU.AU (-s87271077-s.walker-man-50-)
Subject: What do Nuclear Site's Cooling Towers do?
Organization: University of Technology, Sydney
Lines: 12
Distribution: world
NNTP-Posting-Host: acacia.ccsd.uts.edu.au
Summary: Cooling Towers?. Anyone know how they work?
Keywords: Nuclear
Organisation: University of Technology, Sydney, Australia
I really don't know where to post this question so I figured that
this board would be most appropriate.
I was wondering about those massive concrete cylinders that
are ever present at nuclear poer sites. They look like cylinders
that have been pinched in the middle. Does anybody know what the
actual purpose of those things are?. I hear that they're called
'Cooling Towers' but what the heck do they cool?
I hope someone can help
From: jeh@cmkrnl.com
Subject: Re: A question about 120VAC outlet wiring..
Organization: Kernel Mode Systems, San Diego, CA
Lines: 43
In article <1993Apr14.172145.27458@ecsvax.uncecs.edu>, crisp@ecsvax.uncecs.edu (Russ Crisp) writes:
> I'm considering modernizing some old wiring in my home, and
> I need a little advice on outlet wiring.  Several outlets
> are the old 'two prong' type, without the ground.  Naturally,
> the wire feeding these outlets is 12/2, WITHOUT the ground
> wire.  I noticed at the fusebox that some circuits have the
> 12/2 with ground, and that on these circuits, the ground
> wire was tied to the same bus as the neutral (white) wire.
>
> SO..  Here's my question.  It seems to me that I'd have the
> same electrical circuit if I hooked the jumper from the neutral
> over to the ground screw on new 'three prong' grounding outlets.
> What's wrong with my reasoning here?
No.  No.  NOOO!!!
The ground (green) wire is for safety.  No current is supposed to flow in it
under normal conditions.  This means that there's normally no voltage drop in
it either.  It is supposed to be safe to touch the ground wire... even if
you're grounded in some other way at the same time.
The neutral (white) wire is, as Dave Vanderbyl correctly said, the return for
the hot wire.  Since current flows in it, there's a voltage drop.  If you
plug a heavy load into a properly-wired grounded outlet, you can commonly
measure a volt or so of difference between neutral and ground.
They are supposed to be connected together at the breaker panel... but nowhere,
repeat NOwhere, else.  (Well, almost.  There are strange exceptions for things
like sub-panels.)
What you CAN do if you want three-prong outlets without additional wiring is
to use a GFCI outlet (or breaker, but the outlet will be cheaper).  In fact,
depending on where you are putting your new outlet(s), a GFCI may be *required*.
There is a FAQ on electrical wiring, posted regularly to rec.woodworking and
news.answers.  It goes into great detail on these issues (including GFCIs) and
you should probably read it before asking any more questions.  I'll mail a copy
to you, append a copy here, and will ask the writers to cross-post it here in
the future.
--- Jamie Hanrahan, Kernel Mode Systems, San Diego CA
Internet:  jeh@cmkrnl.com  Uucp: uunet!cmkrnl!jeh  CIS: 74140,2055
From: jeh@cmkrnl.com
Subject: Electrical wiring FAQ (was: A question about 120VAC outlet wiring..
Reply-To: wirefaq@ferret.ocunix.on.ca
Keywords: 120 240 AC outlets wiring power shock gfci
Expires: 15 May 93 21:35:16 PDT
Distribution: world
Organization: Kernel Mode Systems, San Diego, CA
Lines: 1547
Since electrical wiring questions do turn up from time to time on
sci.electronics (and the answers aren't always apparent, even to those skilled
in electronics), I am hijacking the following FAQ and posting a copy here.
I've asked the writers to cross-post to sci.electronics in the future.
--- jeh@cmkrnl.com
X-NEWS: cmkrnl news.answers: 6685
Newsgroups: misc.consumers.house,rec.woodworking,news.answers,misc.answers,rec.answers
Subject: Electrical Wiring FAQ
Message-ID: <wirefaq_733900891@ecicrl>
From: clewis@ferret.ocunix.on.ca (Chris Lewis)
Date: 4 Apr 93 05:21:49 GMT
Reply-To: wirefaq@ferret.ocunix.on.ca (Wiring FAQ commentary reception)
Followup-To: poster
Expires: 2 May 93 05:21:31 GMT
Organization: Elegant Communications Inc., Ottawa, Canada
Summary: A series of questions and answers about house wiring
Supersedes: <wirefaq_732691289@ecicrl>
Lines: 1524
Archive-name: electrical-wiring
Last-modified: Sun Feb 21 16:56:10 EST 1993
Frequently Asked Questions on Electrical Wiring
Steven Bellovin (smb@ulysses.att.com)
Chris Lewis (clewis@ferret.ocunix.on.ca)
Comments to (automatic if you reply to this article):
wirefaq@ferret.ocunix.on.ca
This FAQ is formatted as a digest.  Most news readers can
skip from one question to the next by pressing ^G.
Answers to many other topics related to houses can be obtained from
the misc.consumers.house archive; send an empty piece of mail to
house-archive@dg-rtp.dg.com for information.
Changes to previous issue marked with "|" in left column.  Watch
particularly for "NEW" in the Questions list for new or substantively
changed answers.
Note that this is now a registered FAQ - cross-posted to news.answers
and should appear in the FAQ list of lists.
Subject: Questions answered in this FAQ
Introduction/Disclaimers
What is the NEC?  Where can I get a copy?
What is the CEC?  Where can I get a copy?
Can I do my own wiring?  Extra pointers?
What do I need in the way of tools?
What is UL listing?
What is CSA approval?
Are there any cheaper, easier to read books on wiring?
Inspections how and what?  Why should I get my wiring inspected?
My house doesn't meet some of these rules and regulations.
A word on voltages: 110/115/117/120/125/220/240
What does an electrical service look like?
What is a circuit?
"grounding" versus "grounded" versus "neutral".
What does a fuse or breaker do?  What are the differences?
Breakers?  Can't I use fuses?
What size wire should I use?
Where do these numbers come from?
What does "14-2" mean?
What is a "wirenut"/"marrette"/"marr connector".  How are they used?
What is a GFI/GFCI?
Where should GFCIs be used?
Where shouldn't I use a GFCI?
What is the difference between a GFCI outlet and a GFCI breaker?
What's the purpose of the ground prong on an outlet, then?
Why is one prong wider than the other?  Polarization
What kind of outlets do I need in a kitchen?
Where must outlets and switches be in bathrooms?
What is Romex/NM/NMD?  What is BX?  When should I use each?
Should I use plastic or metal boxes?
Junction box positioning?
Can I install a replacement fixture?
What does it mean when the lights brighten when a motor starts?
What is 3 phase power?  Should I use it?  Can I get it in my house?
Is it better to run motors at 110 or 220?
What is this nonsense about 3HP on 110V 15A circuits?
How do I convert two prong receptacles to three prong?
Are you sure about GFCIs and ungrounded outlets?
Should the test button work?
How should I wire my shop?
Underground wiring
Aluminum wiring
I'm buying a house!  What should I do?
What is this weird stuff?  Old style wiring
Where do I buy stuff?
Subject: Introduction/Disclaimers
Although we've done a fair bit of wiring, we are not
electricians, and we cannot be responsible for what you do.  If
you're at all uncertain about what is correct or safe, *don't
do it*.  Contact someone qualified -- a licensed electrician,
or your local electrical inspector.  Electricity is no joke;
mistakes can result in shocks, fires, or electrocution.
Furthermore, our discussion is based on the U.S. National
Electrical Code (NEC) and the Canadian Electrical code (CEC).
To the best of our abilities, we have confirmed every detail
with the electrical code, but we don't quote sections
simply to keep this thing readable.  If you think we're wrong,
we invite you to correct us, but please - quote references!
The NEC and the CEC do not, in and of themselves, have the
force of law.  Many municipalities adopt it en toto.  Others,
however, do not.  Check your with your local building
department (and <provincial> Hydro Inspection Offices in
Canada) to find out what applies in your area.  Also,
your local electrical utility may also have special requirements
for electrical service installation.  Bear in mind, too, that
we say here applies primarily to ordinary single-family
residences.  Multi-family dwellings, mobile homes, commercial
establishments, etc., are sometimes governed by different
rules.
Also note that, contrary to popular belief in the U.S. (and in
some parts of Canada), Canada is not a wholly-owned subsidiary
of the U.S.  Consequently, the NEC does not apply in Canada.
Lots of things are the same, including voltages, line
frequencies, and the laws of physics.  But there are a number
of crucial differences in the regulations.  Where we can, we've
noted them, flagging the relevant passages with ``NEC'' or
``CEC''.
Remember that the CEC and NEC are minimal standards.  It is often
smart to go beyond their minimal requirements.
Subject: What is the NEC?  Where can I get a copy?
The NEC is a model electrical code devised and published by the
National Fire Protection Association, an insurance industry group.
It's revised every three years.  The 1993 version has been released.
You can buy a copy at a decent bookstore, or by calling them directly
at 800-344-3555.  The code exists in several versions.  There's the
full text, which is fairly incomprehensible.  There's an abridged
edition, which has only the sections likely to apply to most houses.
And there's the NEC Handbook, which contains the ``authorized
commentary'' on the code, as well as the full text.  That's the
recommended version.  Unfortunately, there's no handbook for
the abridged edition.  And the full handbook is expensive --
US$65 plus shipping and handling.
Subject: What is the CEC?  Where can I get a copy?
The Canadian Standards Association is an organization made up
of various government agencies, power utilities, insurance
companies, electrical manufacturers and other organizations.
The CSA publishes CSA Standard C22.1 which is updated every two
or three years.  Each province adopts, with some amendments,
this standard and publishes a province-specific code book.
Since each province publishes its own slightly modified
standard, it would be somewhat confusing to obtain the CSA
standard itself.  In this FAQ, "CEC" really means the
appropriate provincial standard.  In particular, this FAQ is
derived from the Ontario Hydro Electrical Safety Code, 20th
edition (1990).  Which is in turn based on CSA C22.1-1990 (16th
edition).  While differences exist between the provinces, an
attempt has been made to avoid specific-to-Ontario detail.
The appropriate provincial code can be obtained from electrical
inspection offices of your provincial power authority.  In
Ontario, it's Ontario Hydro.  The Ontario Hydro book isn't
overly fat.  It's about C$25, and includes mailed updates.  I
hear that these standards are somewhat easier to read than the
equivalent NEC publications.
Don't bother asking in Quebec - DIY wiring is banned throughout
the province.
Subject: Can I do my own wiring?  Extra pointers?
In most places, homeowners are allowed to do their own wiring.
In some, they're not.  Check with your local electrical
inspector.  Most places won't permit you to do wiring on other's
homes for money without a license.  Nor are you permitted to do
wiring in "commercial" buildings.  Multiple dwellings (eg: duplexes)
are usually considered "semi-commercial" or "commercial".  However,
many jurisdictions will permit you to work on semi-commercial
wiring if you're supervised by a licensed electrician - if you can
find one willing to supervise.
If you do your own wiring, an important point:
Do it NEAT and WELL!  What you really want to aim for is a better
job than an electrician will do.  After all, it's your own home,
and it's you or your family that might get killed if you make
a mistake.  An electrician has time pressures, has the skills
and knows the tricks of the trade to do a fast, safe job.
In this FAQ we've consciously given a few recommendations that
are in excess of code, because we feel that it's reasonable,
and will impress the inspector.
The inspector will know that you're an amateur.  You have to
earn his trust.  The best way of doing this is to spend your
time doing as neat a job as possible.  Don't cut corners.
Exceed specifications.  Otherwise, the inspector may get extremely
picky and fault you on the slightest transgressions.
Don't try to hide anything from the inspector.
Use the proper tools.  Ie: don't use a bread knife to strip
wires, or twist wires with your fingers.  The inspector
won't like it, and the results won't be that safe.  And it
takes longer.  And you're more likely to stick a hunk of
12ga wire through your hand that way.
Don't handle house wire when it's very cold (eg: below -10C
or 16F).  Thermoplastic house wire, particularly older types
become very brittle.
Subject: What do I need in the way of tools?
First, there's the obvious -- a hammer, a drill, a few
screwdrivers, both straight and Phillips-head.  If you're
lucky enough to live in Canada (or find a source of CSA-approved
devices) you need Robertson ("square recess") screwdrivers
(#1 and #2) instead of phillips.
For drilling a few holes, a 3/4" or 1" spade bit and 1/4" or
3/8" electric drill will do.  If you're doing a lot, or
are working with elderly lumber, we recommend a 1/2" drill
(right-angle drills are wonderful.  Can be rented) and
3/4" or 1" screw-point auger drill bits.  These bits pull
you through, so they're much faster and less fatiguing, even
in 90 year old hardwood timbers.
Screw-driver bits are useful for drills, expecially if you
install your electrical boxes using screws (drywall screws
work well).
For stripping wire, use a real wire stripper, not a knife or
ordinary wire cutters.  Don't buy the $3 K-mart "combo stripper,
crimper and bottle opener" types.  You should expect to pay
$15 to $20 for a good "plier-type" pair.  It will have sized
stripping holes, and won't nick or grab the wire - it should
be easy to strip wire with it.  One model has a small hole in the
blade for forming exact wire loops for screw terminals.  There
are fancier types (autostrip/cut), but they generally aren't
necessary, and pros usually don't use them.
A pair of diagonal side cutter pliers are useful for clipping ends
in constricted places.  Don't use these for stripping wire.
You will need linesman pliers for twisting wires for wire nuts.
You should have a pair of needle-nose pliers for fiddling
inside boxes and closing loops, but it's better to form wire
loops with a "loop former hole" on your wire stripper - more
accurate.
If you're using non-metallic cable, get a cable stripper for
removing the sheath.  Or, do what some pros do, they nick the
end of the sheath, grab the ground wire with a pair of pliers,
and simply rip the sheath back using the ground wire as a
"zipper", and cut the sheath off.  You shouldn't try to strip
the sheath with a knife point, because it's too easy to
slash the insulation on the conductors.  Apparently Stanley
utility knives fitted with linoleum cutters (hooked blades)
can be used to strip sheath, but there is still the possibility
that you'll gouge the conductors.
For any substantial amount of work with armored cable, it's well
worth your while to invest in a rotary cable splitter (~US$ 18).
Hack saws are tricky to use without cutting into the wire
or the insulation.
Three-prong outlet testers are a quick check for properly-wired
outlets.  About $6.  Multimeters tell you more, but are a lot more
expensive, and probably not worth it for most people.  A simple
voltage sensor, which can detect potential through an insulated
wire not supplying any devices, is extremely helpful; they cost
about US$ 10 at Radio Shack.
You should have a voltage detector - to check that the wires are
dead before doing work on them.  Neon-bulb version are cheap ($2-3)
and work well.  If you get more serious, a "audible alarm" type is
good for tracing circuits without a helper.  (Though I've been known
to lock the drill on, and hit breakers until the scream stops ;-)
For running wires through existing walls, you need fish tape.
Often, two tapes are needed, though sometimes, a bent hanger or
a length of thin chain will suffice.  Fish tapes can be rented.
Electrical tape.  Lots of it ;-)  Seriously, a good and competent
wiring job will need very little tape.  The tape is useful for
wrapping dicy insulation in repair work.  Another use is to wrap
around the body of outlets and switches to cover the termination
screws - I don't do this, but drywall contractors prefer it (to
prevent explosions when the drywall knife collides with a live outlet
that has no cover plate).
Subject: What is UL listing?
The UL stands for "Underwriters Laboratory".  It used to be
an Insurance Industry organization, but now it is independent
and non-profit.  It tests electrical components and equipment
for potential hazards.  When something is UL-listed, that means
that the UL has tested the device, and it meets their requirements
for safety - ie: fire or shock hazard.  It doesn't necessarily
mean that the device actually does what it's supposed to, just
that it probably won't kill you.
The UL does not have power of law in the U.S. -- you are
permitted to buy and install non-UL-listed devices.  However,
insurance policies sometimes have clauses in them that will
limit their liability in case of a claim made in response to
the failure of a non-UL-listed device.  Furthermore, in
many situations the NEC will require that a wiring component
used for a specific purpose is UL-listed for that purpose.
Indirectly, this means that certain parts of your wiring
must be UL-listed before an inspector will approve it and/or
occupancy permits issued.
Subject: What is CSA approval?
Every electrical device or component must be certified by the
Canadian Standards Association before it can be sold in
Canada.  Implicit in this is that all wiring must be done
with CSA-approved materials.  They perform testing similar to
the UL (a bit more stringent), except that CSA approval is
required by law.
Again, like the UL, if a fire was caused by non-CSA-approved
equipment, your insurance company may not have to pay the
claim.
In Canada, there is a branch organization of the UL, called ULC
(UL of Canada).  ULC does not have power of law, and seems to
be more a liason group between the CSA and insurance
companies.
Subject: Are there any cheaper, easier to read books on wiring?
USA: The following three books were suggested by our readers
Residential Wiring
by Jeff Markell,
Craftsman Books,
Carlsbad CA for $18.25. ISBN 0-934041-19-9.
Practical Electrical Wiring
Residential, Farm and Industrial,  Based on the National
Electrical Code    ANSI/NFPA 70
Herbert P. Richter and W. Creighton Schwan
McGraw-Hill Book Co.
Wiring Simplified
H. P. Richter and W. C. Schwan
Park Publishing Co.
Try to make sure that the book is based on the latest NEC
revision.  Which is currently 1990.
Canada: P.S. Knight authors and publishes a book called
"Electrical Code Simplified".  There appears to be a version
published specific to each province, and is very tied into the
appropriate provincial code.  It focuses on residential wiring,
and is indispensible for Canadian DIY'ers.  It is better to get
this book than the CEC unless you do a lot of wiring (or answer
questions on the net ;-).
It is updated each time the provincial codes are.  This book is
available at all DIY and hardware stores for less than C$10.
Subject: Inspections how and what?  Why should I get my wiring inspected?
Most jurisdictions require that you obtain a permit and
inspections of any wiring that is done.  Amongst other more
mundane bureaucratic reasons (like insurance companies not
liking to have to pay claims), a permit and inspections
provides some assurance that you, your family, your neighbors
or subsequent owners of your home don't get killed or lose
their homes one night due to a sloppy wiring job.
Most jurisdictions have the power to order you to vacate your
home, or order you to tear out any wiring done without a
permit.  California, for instance, is particularly nasty about
this.
If fire starts in your home, and un-inspected wiring is at
fault, insurance companies will often refuse to pay the damage
claims.
In general, the process goes like this:
- you apply to your local inspections office or building
department for a permit.  You should have a sketch or
detailed drawing of what you plan on doing.  This is
a good time to ask questions on any things you're not
sure of.  If you're doing major work, they may impose
special conditions on you, require loading
calculations and ask other questions.  At this point
they will tell you which inspections you will need.
- If you're installing a main panel, you will need to
have the panel and service connections inspected
before your power utility will provide a connection.
This is sometimes done by the local power authority
rather than the usual inspectors.
- After installing the boxes and wiring, but before
the insulation/walls go up, you will need a
"rough-in" inspection.
- After the walls are up, and the wiring is complete,
you will need a "final inspection".
Subject: My house doesn't meet some of these rules and regulations.
Do I have to upgrade?
In general, there is no requirement to upgrade older dwellings,
though there are some exceptions (ie: smoke detectors in some
cases).  However, any new work must be done according to the
latest electrical code.  Also, if you do ``major'' work, you
may be required to upgrade certain existing portions or all
of your system.  Check with your local electrical inspector.
Subject: A word on voltages: 110/115/117/120/125/220/240
One thing where things might get a bit confusing is the
different numbers people bandy about for the voltage of
a circuit.  One person might talk about 110V, another 117V
or another 120V.  These are all, in fact, exactly the same
thing...  In North America the utility companies are required
to supply a split-phase 240 volt (+-5%) feed to your house.
This works out as two 120V +- 5% legs.  Additionally, since there
are resistive voltage drops in the house wiring, it's not
unreasonable to find 120V has dropped to 110V or 240V has dropped
to 220V by the time the power reaches a wall outlet.  Especially
at the end of an extension cord or long circuit run.  For a number
of reasons, some historical, some simple personal orneryness,
different people choose call them by slightly different numbers.
This FAQ has chosen to be consistent with calling them "110V" and
"220V", except when actually saying what the measured voltage will
be.  Confusing?  A bit.  Just ignore it.
One thing that might make this a little more understandable
is that the nameplates on equipment ofen show the lower (ie: 110V
instead of 120V) value.  What this implies is that the device
is designed to operate properly when the voltage drops that
low.
208V is *not* the same as 240V.  208V is the voltage between
phases of a 3-phase "Y" circuit that is 120V from neutral to any
hot.   480V is the voltage between phases of a 3-phase "Y"
circuit that's 277V from hot to neutral.
In keeping with 110V versus 120V strangeness, motors intended
to run on 480V three phase are often labelled as 440V...
Subject: What does an electrical service look like?
There are logically four wires involved with supplying the
main panel with power.  Three of them will come from the utility
pole, and a fourth (bare) wire comes from elsewhere.
The bare wire is connected to one or more long metal bars pounded
into the ground, or to a wire buried in the foundation, or sometimes
to the water supply pipe (has to be metal, continuous to where
the main water pipe entering the house.  Watch out for galvanic
action conductivity "breaks" (often between copper and iron pipe)).
This is the "grounding conductor".  It is there to make sure that
the third prong on your outlets is connected to ground.  This wire
normally carries no current.
One of the other wires will be white (or black with white or
yellow stripes, or sometimes simply black).  It is the neutral wire.
It is connected to the "centre tap" (CEC; "center tap" in the
NEC) of the distribution transformer supplying the power.  It
is connected to the grounding conductor in only one place (often
inside the panel).  The neutral and ground should not be connected
anywhere else.  Otherwise, weird and/or dangerous things may happen.
Furthermore, there should only be one grounding system in
a home.  Some codes require more than one grounding electrode.
These will be connected together, or connected to the neutral
at a common point - still one grounding system.  Adding additional
grounding electrodes connected to other portions of the house
wiring is unsafe and contrary to code.
If you add a subpanel, the ground and neutral are usually
brought as separate conductors from the main panel, and are
not connected together in the subpanel (ie: still only one
neutral-ground connection).  However, in some situations
(certain categories of separate buildings) you actually do
have to provide a second grounding electrode - consult your
inspector.
The other two wires will usually be black, and are the "hot"
wires.  They are attached to the distribution transformer as
well.
The two black wires are 180 degrees out of phase with each
other.  This means if you connect something to both hot wires,
the voltage will be 220 volts.  If you connect something to the
white and either of the two blacks you will get 110V.
Some panels seem to only have three wires coming into them.
This is either because the neutral and ground are connected
together at a different point (eg: the meter or pole) and one
wire is doing dual-duty as both neutral and ground, or in some
rare occasions, the service has only one hot wire (110V only
service).
Subject: What is a circuit?
Inside the panel, connections are made to the incoming wires.
These connections are then used to supply power to selected
portions of the home.  There are three different combinations:
1) one hot, one neutral, and ground: 110V circuit.
2) two hots, no neutral, and ground: 220V circuit.
3) two hots, neutral, and ground: 220V circuit + neutral,
and/or two 110V circuits with a common neutral.
(1) is used for most circuits supplying receptacles and
lighting within your house.  (3) is usually used for supplying
power to major appliances such as stoves, and dryers - they
often have need for both 220V and 110V, or for bringing several
circuits from the panel box to a distribution point.  (2) is
usually for special 220V motor circuits, electric heaters, or
air conditioners.
[Note: In the US, the NEC frequently permits a circuit similar
to (2) be used for stoves and dryers - namely, that there
are two hot wires, and a wire that does dual duty as neutral
and ground, and is connected to the frame as well as providing
the neutral for 110V purposes - three prong plugs instead
of four (*only* for stoves/dryers connected to the main panel.
When connected to most sub-panels, 4 prong plugs and receptacles
are required).  In our not-so-humble opinion this is crazy, but
the NFPA claims that this practice was re-evaluated for the 1992 NEC,
and found to be safe.  Check your local codes, or inquire as to
local practice -- there are restrictions on when this is
permissible.]
(1) is usually wired with three conductor wire: black for hot,
white for neutral, and bare for grounding.
(2) and (3) have one hot wire coloured red, the other black, a
bare wire for grounding, and in (3) a white wire for neutral.
You will sometimes see (2) wired with just a black, white and ground
wire.  Since the white is "hot" in this case, both the NEC and CEC
requires that the white wire be "permanently marked" at the ends
to indicate that it is a live wire.  Usually done with paint, nail
polish or sometimes electrical tape.
Each circuit is attached to the main wires coming into the
panel through a circuit breaker or fuse.
There are, in a few locales, circuits that look like (1), (2)
or (3) except that they have two bare ground wires.  Some places
require this for hot tubs and the like (one ground is "frame ground",
the other attaches to the motor).  This may or may not be an
alternative to GFCI protection.
Subject: "grounding" versus "grounded" versus "neutral".
According to the terminology in the CEC and NEC, the
"grounding" conductor is for the safety ground, i.e., the green
or bare wire.  The word "neutral" is reserved for the white when
you have a circuit with more than one "hot" wire.  Since the white
wire is connected to neutral and the grounding conductor inside the
panel, the proper term is "grounded conductor".  However, the
potential confusion between "grounded conductor" and "grounding
conductor" can lead to potentially lethal mistakes - you should
never use the bare wire as a "grounded conductor" or white wire
as the "grounding conductor", even though they are connected
together in the panel.
[But not in subpanels - subpanels are fed neutral and ground
separately from the main panel.  Usually.]
In the trade, and in common usage, the word "neutral" is used
for "grounded conductor".  This FAQ uses "neutral" simply to
avoid potential confusion.  We recommend that you use "neutral"
too.  Thus the white wire is always (except in some light
switch applications) neutral.  Not ground.
Subject: What does a fuse or breaker do?  What are the differences?
Fuses and circuit breakers are designed to interrupt the power
to a circuit when the current flow exceeds safe levels.  For
example, if your toaster shorts out, a fuse or breaker should
"trip", protecting the wiring in the walls from melting.  As
such, fuses and breakers are primarily intended to protect the
wiring -- UL or CSA approval supposedly indicates that the
equipment itself won't cause a fire.
Fuses contain a narrow strip of metal which is designed to melt
(safely) when the current exceeds the rated value, thereby
interrupting the power to the circuit.  Fuses trip relatively
fast.  Which can sometimes be a problem with motors which have
large startup current surges.  For motor circuits, you can use
a "time-delay" fuse (one brand is "fusetron") which will avoid
tripping on momentary overloads.  A fusetron looks like a
spring-loaded fuse.  A fuse can only trip once, then it must be
replaced.
Breakers are fairly complicated mechanical devices.  They
usually consist of one spring loaded contact which is latched
into position against another contact.  When the current flow
through the device exceeds the rated value, a bimetallic strip
heats up and bends.  By bending it "trips" the latch, and the
spring pulls the contacts apart.  Circuit breakers behave
similarly to fusetrons - that is, they tend to take longer to
trip at moderate overloads than ordinary fuses.  With high
overloads, they trip quickly.  Breakers can be reset a finite
number of times - each time they trip, or are thrown
when the circuit is in use, some arcing takes place, which
damages the contacts.  Thus, breakers should not be used in
place of switches unless they are specially listed for the
purpose.
Neither fuses nor breakers "limit" the current per se.  A dead
short on a circuit can cause hundreds or sometimes even
thousands of amperes to flow for a short period of time, which
can often cause severe damage.
Subject: Breakers?  Can't I use fuses?
Statistics show that fuse panels have a significantly higher
risk of causing a fire than breaker panels.  This is usually
due to the fuse being loosely screwed in, or the contacts
corroding and heating up over time, or the wrong size fuse
being installed, or the proverbial "replace the fuse with a
penny" trick.
Since breakers are more permanently installed, and have better
connection mechanisms, the risk of fire is considerably less.
Fuses are prone to explode under extremely high overload.  When
a fuse explodes, the metallic vapor cloud becomes a conducting
path.  Result? from complete meltdown of the electrical panel,
melted service wiring, through fires in the electrical
distribution transformer and having your house burn down.
Breakers don't do this.
Many jurisdictions, particularly in Canada, no longer permit
fuse panels in new installations.  The NEC does permit new
fuse panels in some rare circumstances (requiring the special
inserts to "key" the fuseholder to specific size fuses)
Some devices, notably certain large air conditioners, require fuse
protection in addition to the breaker at the panel.  The fuse
is there to protect the motor windings from overload.  Check the
labeling on the unit.  This is usually only on large permanently
installed motors.  The installation instructions will tell you
if you need one.
Subject: What size wire should I use?
For a 20 amp circuit, use 12 gauge wire.  For a 15 amp circuit,
you can use 14 gauge wire (in most locales).  For a long run,
though, you should use the next larger size wire, to avoid
voltage drops.  12 gauge is only slightly more expensive than
14 gauge, though it's stiffer and harder to work with.
Here's a quick table for normal situations.  Go up a size for
more than 100 foot runs, when the cable is in conduit, or
ganged with other wires in a place where they can't dissipate
heat easily:
Gauge		Amps
14		15
12		20
10		30
8		40
6		65
We don't list bigger sizes because it starts getting very dependent
on the application and precise wire type.
Subject: Where do these numbers come from?
There are two considerations, voltage drop and heat buildup.
The smaller the wire is, the higher the resistance is.  When
the resistance is higher, the wire heats up more, and there is
more voltage drop in the wiring.  The former is why you need
higher-temperature insulation and/or bigger wires for use in
conduit; the latter is why you should use larger wire for long
runs.
Neither effect is very significant over very short distances.
There are some very specific exceptions, where use of smaller
wire is allowed.  The obvious one is the line cord on most
lamps.  Don't try this unless you're certain that your use fits
one of those exceptions; you can never go wrong by using larger
wire.
Subject: What does "14-2" mean?
This is used to describe the size and quantity of conductors
in a cable.  The first number specifies the gauge.  The second
the number of current carrying conductors in the wire - but
remember there's usually an extra ground wire.  "14-2" means
14 gauge, two insulated current carrying wires, plus bare ground.
-2 wire usually has a black, white and bare ground wire.  Sometimes
the white is red instead for 220V circuits without neutral.  In
the latter case, the sheath is usually red too.
-3 wire usually has a black, red, white and bare ground wire.
Usually carrying 220V with neutral.
Subject: What is a "wirenut"/"marrette"/"marr connector"?  How are they
used?
A wire nut is a cone shaped threaded plastic thingummy that's used
to connect wires together.  "Marrette" or "Marr connector"
are trade names.  You'll usually use a lot of them in DIY wiring.
In essence, you strip the end of the wires about an inch, twist them
together, then twist the wirenut on.
Though some wirenuts advertise that you don't need to twist the
wire, do it anyways - it's more mechanically and electrically
secure.
There are many different sizes of wire nut.  You should check
that the wire nut you're using is the correct size for the
quantity and sizes of wire you're connecting together.
Don't just gimble the wires together with a pair of pliers or
your fingers.  Use a pair of blunt nose ("linesman") pliers,
and carefully twist the wires tightly and neatly.  Sometimes
it's a good idea to trim the resulting end to make sure it
goes in the wirenut properly.
Some people wrap the "open" end of the wirenut with electrical
tape.  This is probably not a good idea - the inspector may
tear it off during an inspection.  It's usually done because
a bit of bare wire is exposed outside the wire nut - instead
of taping it, the connection should be redone.
Subject: What is a GFI/GFCI?
A GFCI is a ``ground-fault circuit interrupter''.  It measures
the current current flowing through the hot wire and the
neutral wire.  If they differ by more than a few milliamps, the
presumption is that current is leaking to ground via some other
path.  This may be because of a short circuit to the chassis of
an appliance, or to the ground lead, or through a person.  Any
of these situations is hazardous, so the GFCI trips, breaking
the circuit.
GFCIs do not protect against all kinds of electric shocks.  If,
for example, you simultaneously touched the hot and neutral
leads of a circuit, and no part of you was grounded, a GFCI
wouldn't help.  All of the current that passed from the hot
lead into you would return via the neutral lead, keeping the
GFCI happy.
The two pairs of connections on a GFCI outlet are not symmetric.
One is labeled LOAD; the other, LINE.  The incoming power feed
*must* be connected to the LINE side, or the outlet will not be
protected.  The LOAD side can be used to protect all devices
downstream from it.  Thus, a whole string of outlets can be
covered by a single GFCI outlet.
Subject: Where should GFCIs be used?
The NEC mandates GFCIs for 110V, 15A or 20A single phase
outlets, in bathrooms, kitchens within 6' of the sink, garages,
unfinished basements or crawl spaces, outdoors, near a pool, or
just about anywhere else where you're likely to encounter water
or dampness.  There are exceptions for inaccessible outlets,
those dedicated to appliances ``occupying fixed space'',
typically refrigerators and freezers, and for sump pumps and
laundry appliances.
The CEC does not mandate as many GFCIs.  In particular, there
is no requirement to protect kitchen outlets, or most garage or
basement outlets.  Basement outlets must be protected if you
have a dirt floor, garage outlets if they're near the door to
outside.  Bathrooms and most exterior outlets must have GFCIs.
Even if you are not required to have GFCI protection, you may
want to consider installing it anyway.  Unless you need a GFCI
breaker (see below), the cost is low.  In the U.S., GFCI
outlets can cost as little as US$8.  (Costs are a bit higher in
Canada:  C$12.)  Evaluate your own risk factors.  Does your
finished basement ever get wet?  Do you have small children?
Do you use your garage outlets to power outdoor tools?  Does
water or melted snow ever puddle inside your garage?
Subject: Where shouldn't I use a GFCI?
GFCIs are generally not used on circuits that (a) don't pose a
safety risk, and (b) are used to power equipment that must run
unattended for long periods of time.  Refrigerators, freezers,
and sump pumps are good examples.  The rationale is that GFCIs
are sometimes prone to nuisance trips.  Some people claim that
the inductive delay in motor windings can cause a momentary
current imbalance, tripping the GFCI.  Note, though, that most
GFCI trips are real; if you're getting a lot of trips for no
apparent reason, you'd be well-advised to check your wiring
before deciding that the GFCI is broken or useless.
Subject: What is the difference between a GFCI outlet and a GFCI breaker?
For most situations, you can use either a GFCI outlet as the
first device on the circuit, or you can install a breaker with
a built-in GFCI.  The former is generally preferred, since GFCI
breakers are quite expensive.  For example, an ordinary GE
breaker costs ~US$5; the GFCI model costs ~US$35.  There is one
major exception:  if you need to protect a ``multi-wire branch
circuit'' (two or more circuits sharing a common neutral wire),
such as a Canadian-style kitchen circuit, you'll need a
multi-pole GFCI breaker.  Unfortunately, these are expensive;
the cost can range into the hundreds of dollars, depending on
what brand of panel box you have.  But if you must protect such
a circuit (say, for a pool heater), you have no choice.
One more caveat -- GFCI outlets are bulky.  You may want to use
an oversize box when installing them.  On second thought, use
large (actually deep) boxes everywhere.  You'll thank yourself for it.
Incidentally, if you're installing a GFCI to ensure that one
specific outlet is protected (such as a bathroom), you don't
really have to go to all of the trouble to find the first
outlet in the circuit, you could simply find the first outlet
in the bathroom, and not GFCI anything upstream of it.  But
protecting the whole circuit is preferred.
When you install a GFCI, it's a good idea to use the little
"ground fault protected" stickers that come with it and mark
the outlets downstream of the GFCI.  You can figure out which
outlets are "downstream", simply by tripping the GFCI with the
test button and see which outlets are dead.
Subject: What's the purpose of the ground prong on an outlet, then?
Apart from their use in electronics, which we won't comment on,
and for certain fluorescent lights (they won't turn on without
a good ground connection), they're intended to guard against
insulation failures within the device.  Generally, the case of
the appliance is connected to the ground lead.  If there's an
insulation failure that shorts the hot lead to the case, the
ground lead conducts the electricity away safely (and possibly
trips the circuit breaker in the process).  If the case is not
grounded and such a short occurs, the case is live -- and if
you touch it while you're grounded, you'll get zapped.  Of
course, if the circuit is GFCI-protected, it will be a very
tiny zap -- which is why you can use GFCIs to replace
ungrounded outlets (both NEC and CEC).
There are some appliances that should *never* be grounded.  In
particular, that applies to toasters and anything else with
exposed conductors.  Consider:  if you touch the heating
electrode in a toaster, and you're not grounded, nothing will
happen.  If you're slightly grounded, you'll get a small shock;
the resistance will be too high.  But if the case were
grounded, and you were holding it, you'd be the perfect path to
ground...
Subject: Why is one prong wider than the other?  Polarization
Nowadays, many two-prong devices have one prong wider than the
other.  This is so that the device could rely (not guaranteed!)
on one specific wire being neutral, and the other hot.
This is particularly advantageous in light fixtures, where the
the shell should neutral (safety), or other devices which want to
have an approximate ground reference (ie: some radios).
Most 2-prong extension cords have wide prongs too.
This requires that you wire your outlets and plugs the right
way around.  You want the wide prong to be neutral, and the
narrow one hot.  Most outlets have a darker metal for the
hot screw, and lighter coloured screw for the neutral.
If not, you can usually figure out which is which by which
prong the terminating screw connects to.
Subject: What kind of outlets do I need in a kitchen?
The NEC requires at least two 20 amp ``small appliance
circuits'' for kitchens.  The CEC requires split-duplex
receptacles.  Outlets must be installed such that no point is more
than 24" (NEC) (900 mm CEC) from an outlet.  Every counter wider
than 12" (NEC) or 300 mm (CEC) must have at least one outlet.
The circuit these outlets are on may not feed any outlets except
in the kitchen, pantry, or dining room.  Furthermore, these circuits
are in addition to any required for refrigerators, stoves, microwaves,
lighting, etc.  Non-dedicated outlets within 6' of a sink *must* be
protected by a GFCI (NEC only).
Split duplex receptacles are fed with a 220V circuit.  The tab
is broken on the hot side of the outlet, and one hot goes to
the upper outlet, and the other hot goes to the lower outlet.
The neutral connects to both outlets through one screw.  When
"carrying through" to another outlet, the neutral must be
pigtailed, such that removing the outlet, or having the neutral
connection fall off doesn't cause the neutral to disconnect
from downstream outlets.
Subject: Where must outlets and switches be in bathrooms?
There must be at least one outlet in each bathroom, adjacent to
the sink, in addition to any outlet that may be incorporated in
the light fixture.  All such outlets *must* be GFCI-protected.
Subject: What is Romex/NM/NMD?  What is BX?  When should I use each?
Romex is a brand name for a type of plastic insulated wire.
Sometimes called non-metallic sheath.  The formal name is NM.
This is suitable for use in dry, protected areas (ie: inside
stud walls, on the sides of joists etc.), that are not subject
to mechanical damage or excessive heat.  Most newer homes are
wired almost exclusively with NM wire.  There are several
different categories of NM cable.
BX cable -- technically known as armored cable or "AC" has a
flexible aluminum or steel sheath over the conductors and is
fairly resistant to damage.
TECK cable is AC with an additional external thermoplastic
sheath.
Protection for cable in concealed locations: where NM or AC cable
is run through studs, joists or similar wooden members, the outer
surface of the cable must be kept at least 32mm/1.25" (CEC & NEC)
from the edges of the wooden members, or the cable should be protected
from mechanical injury.  This latter protection can take the form of
metal plates (such as spare outlet box ends) or conduit.
[Note: inspector-permitted practise in Canada suggests that armored
cable, or flexible conduit can be used as the mechanical protection,
but this is technically illegal.]
Additional protection recommendations (these are rules in the
Canadian codes - they are reasonable answers to the vague
references to "exposed to mechanical damage" in both the NEC
and CEC):
- NM cable should be protected against mechanical damage
where it passes through floors or on the surface of walls
in exposed locations under 5 feet from the floor.
Ie: use AC instead, flexible conduit, wooden guards etc.
- Where cable is suspended, as in, connections to furnaces
or water heaters, the wire should be protected.  Canadian
practise is usually to install a junction or outlet
box on the wall, and use a short length of AC cable
or NM cable in flexible conduit to "jump" to the appliance.
Stapling NM to a piece of lumber is also sometimes used.
- Where NM cable is run in close proximity to heating
ducts or pipe, heat transfer should be minimized by
means of a 25mm/1" air space, or suitable insulation
material (a wad of fiberglass).
- NM cable shall be supported within 300mm/1' of every box
or fitting, and at intervals of no more than 1.5m/5'.
Holes in joists or studs are considered "supports".
Some slack in the cable should be provided adjacent to
each box.  [while fishing cable is technically in violation,
it is permitted where "proper" support is impractical]
- 2 conductor NM cable should never be stapled on edge.
[Knight also insists on only one cable per staple, referring
to the "workmanship" clause, but this seems more honoured
in the breach...]
- cable should never be buried in plaster, cement or
similar finish.
- cable should be protected where it runs behind baseboards.
- Cable may not be run on the upper edge of ceiling joists
or the lower edges of rafters where the headroom is more
than 1m (39").
Whenever BX cable is terminated at a box with a clamp, small
plastic bushings must be inserted in the end of the cable to
prevent the clamps forcing the sharp ends of the armor through
the insulation.
BX is sometimes a good idea in a work shop unless covered by
solid wall coverings.
In places where damage is more likely (like on the back wall of
a garage ;-), you may be required to use conduit, a
UL- (or CSA-) approved metal pipe.  You use various types of
fittings to join the pipe or provide entrance/exit for the
wire.
Service entrances frequently use a plastic conduit.
In damp places (eg: buried wiring to outdoor lighting) you will
need special wire (eg: CEC NMW90, NEC UF).  NMW90 looks like
very heavy-duty NMD90.  You will usually need short lengths of
conduit where the wire enters/exits the ground.  [See underground
wiring section.]
Thermoplastic sheath wire (such as NM, NMW etc.) should not be
exposed to direct sunlight unless explicitly approved for that
purpose.
Many electrical codes do not permit the routing of wire through
furnace ducts, including cold air return plenums constructed
by metal sheeting enclosing joist spaces.   The reason for this
is that if there's a fire, the ducting will spread toxic gasses
from burning insulation very rapidly through the building.
Teflon insulated wire is permitted in plenums in many areas.
Canada appears to use similar wire designations to the US,
except that Canadian wire designations usually include the
temperature rating in Celsius.  Eg: "AC90" versus "AC".
In the US, NM-B is 90 degrees celcius.
NOTE: local codes vary.  This is one of the items that changes
most often.  Eg: Chicago codes require conduit *everywhere*.
There are very different requirements for mobile homes.
Check your local codes, *especially* if you're doing anything
that's the slightest out of the ordinary.
Wire selection table (incomplete - the real tables are enormous,
uncommon wire types or applications omitted)
Condition			Type	CEC	NEC
Exposed/Concealed dry		plastic	NMD90	NM
armor	AC90	AC
TECK90
Exposed/Concealed damp		plastic	NMD90	NMC
armor	ACWU90
TECK90
Exposed/Concealed wet		plastic	NMWU90
armor	ACWU90
TECK90
Exposed to weather		plastic	NMWU
TW etc.
armor	TECK90
Direct earth burial/		plastic	NMWU*	UF
Service entrance			RWU
TWU
armor	RA90
TECK90
ACWU90
[* NMWU not for service entrance]
Subject: Should I use plastic or metal boxes?
The NEC permits use of plastic boxes with non-metallic cable
only.  The reasoning is simple -- with armored cable, the box
itself provides ground conductor continuity.  U.S. plastic
boxes don't use metal cable clamps.
The CEC is slightly different.  The CEC never permits cable
armor as a grounding conductor.  However, you must still
provide ground continuity for metallic sheath.  The CEC also
requires grounding of any metal cable clamps on plastic boxes.
The advantage of plastic boxes is comparatively minor even for
non-metallic sheathed cable -- you can avoid making one ground
connection and they sometimes cost a little less.  On the other
hand, plastic boxes are more vulnerable to impacts.  For
exposed or shop wiring, metal boxes are probably better.
Subject: Junction box positioning?
A junction box is a box used only for connecting wires together.
Junction boxes must be located in such a way that they're accessible
later.  Ie: not buried under plaster.  Excessive use of junction
boxes is often a sign of sloppy installation, and inspectors may
get nasty.
Subject: Can I install a replacement light fixture?
In general, one can replace fixtures freely, subject to a few
caveats.  First, of course, one should check the amperage
rating of the circuit.  If your heart is set on installing half
a dozen 500 watt floodlights, you may need to run a new wire
back to the panel box.  But there are some more subtle
constraints as well.  For example, older house
wiring doesn't have high-temperature insulation.  The excess
heat generated by a ceiling-mounted lamp can and will cause the
insulation to deteriorate and crack, with obvious bad results.
Some newer fixtures are specifically marked for high
temperature wire only.  (You may find, in fact, that your
ceiling wiring already has this problem, in which case
replacing any devices is a real adventure.)
Other concerns include providing a suitable ground for some
fluorescent fixtures, and making sure that the ceiling box and
its mounting are strong enough to support the weight of a heavy
chandelier or ceiling fan.  You may need to install a new box
specifically listed for this purpose.  A 2x4 across the ceiling
joists makes a good support.  Metal brackets are also available
that can be fished into ceilings thru the junction box hole and
mounted between the joists.
There are special rules for recessed light fixtures such as
"pot" lamps or heat lamps.  When these are installed in insulated
ceilings, they can present a very substantial fire hazard.
The CEC provides for the installation of pot lamps in insulated
ceilings, provided that the fixture is boxed in a "coffin" (usually
8'x16"x12" - made by making a pair of joists 12" high, and covering
with plywood) that doesn't have any insulation.  (Yes, that's 8 *feet*
long)
NEC rules are somewhat less stringent.  They require at least 3"
clearance between the fixture and any sort of thermal insulation.
The rules also say that one should not obstruct free air movement,
which means that a CEC-style ``coffin'' might be worthwhile.
Presumably, that's up to the local inspector.  [The CEC doesn't
actually mandate the coffin per-se, this seems to be an inspector
requirement to make absolutely certain that the fixture can't get
accidentally buried in insulation.  Ie: if you have insulation blown
in later.]
There are now fixtures that contain integral thermal cutouts and
fairly large cases that can be buried directly in insulation.  They are
usually limited to 75 watt bulbs, and are unfortunately, somewhat
more expensive than the older types.  Before you use them, you should
ensure that they have explicit UL or CSA approval for such uses.
Follow the installation instructions carefully; the prescribed location
for the sensor can vary.
There does not yet appear to be a heat lamp fixture that is approved
for use in insulation.  The "coffin" appears the only legal approach.
Subject: What does it mean when the lights brighten when a motor starts?
This usually means that the neutral wire in the panel is
loose.  Depending on the load balance, one hot wire may end up
being more than 110V, and the other less than 110V, with
respect to ground.  This is a very hazardous situation - it can
destroy your electronic equipment, possibly start fires, and in
some situations electrocute you (ie: some US jurisdictions
require the stove frame connected to neutral).
If this happens, contact your electrical authority immediately
and have them come and check out the problem.
Note: a brief (< 1 second) brightening is sometimes normal with
lighting and motors on the same 220V with neutral circuit.  A
loose main panel neutral will usually show increased brightness
far longer than one second.  In case of doubt, get help.
Subject: What is 3 phase power?  Should I use it?  Can I get it in my house?
Three phase power has three "hot" wires, 120 degrees out of
phase with each other.  These are usually used for large motors
because it is more "efficient", provides a bit more starting torque,
and because the motors are simpler and hence cheaper.
You're most likely to encounter a 3 phase circuit that shows
110 volts between any hot and ground, and 208 volts between
any two hots.  The latter shows the difference between a normal
220V/110V common neutral circuit, which is 240 volts between the
two hots.  There are 3 phase circuits with different voltages.
Bringing in a 3 phase feed to your house is usually
ridiculously expensive, or impossible.  If the equipment you
want to run has a standard motor mount, it is *MUCH* cheaper to
buy a new 110V or 220V motor for it.  In some cases it is
possible to run 3 phase equipment on ordinary power if you have
a "capacitor start" unit, or use a larger motor as a
(auto-)generator.  These are tricky, but are a good solution if
the motor is non-standard size, or too expensive or too big to
replace.  The Taunton Press book ``The Small Shop'' has an
article on how to do this if you must.
Note that you lose any possible electrical efficiency by using
such a converter.  The laws of thermodynamics guarantee that.
Subject: Is it better to run motors at 110 or 220?
Theoretically, it doesn't make any difference.  However, there
is a difference is the amount of power lost in the supply
wiring.  All things being equal, a 220V motor will lose 4 times
less power in the house wiring than a 110V motor.  This also
means that the startup surge loss will be less, and the motor
will get to speed quicker.  And in some circumstances, the
smaller power loss will lead to longer motor life.
This is usually irrelevant unless the supply wires are more
than 50 feet long.
Subject: What is this nonsense about 3HP on 110V 15A circuits?
It is a universal physical law that 1 HP is equal to 746
watts.  Given heating loss, power factor and other inefficiencies,
it is usually best to consider 1 HP is going to need 1000-1200
watts.  A 110V 15A circuit can only deliver 1850 watts to a motor,
so it cannot possibly be more than approximately 2 HP.  Given rational
efficiency factors, 1.5HP is more like it.
Some equipment manufacturers (Sears in particular, most router
manufacturers in general ;-) advertise a HP rating that is far
in excess of what is possible.  They are giving you a "stall
horsepower" or similar.  That means the power is measured when
the motor is just about to stop turning because of the load.
What they don't mention is that if you kept it in that
condition for more than a few seconds hopefully your breaker
will trip, otherwise the motor will melt -- it's drawing far
more current than it can continuously.
When comparing motors, compare the continuous horsepower.  This
should be on the motor nameplate.  If you can't find that figure,
check the amperage rating, which is always present.
Subject: How do I convert two prong receptacles to three prong?
Older homes frequently have two-prong receptacles instead
of the more modern three.  These receptacles have no safety
ground, and the cabling usually has no ground wire.  Neither
the NEC or CEC permits installing new 2 prong receptacles anymore.
There are several different approaches to solving this:
1) If the wiring is done through conduit or BX, and the
conduit is continuous back to the panel, you can connect
the third prong of a new receptacle to the receptacle
box.  NEC mainly - CEC frowns on this practise.
2) If there is a copper cold water pipe going nearby, and
it's continuous to the main house ground point, you can
run a conductor to it from the third prong.
3) Run a ground conductor back to the main panel.
4) Easiest: install a GFCI receptacle.  The ground lug
should not be connected to anything, but the GFCI
protection itself will serve instead.  The GFCI
will also protect downstream (possibly also two prong
outlets).  If you do this to protect downstream outlets,
the grounds must not be connected together.  Since it
wouldn't be connected to a real ground, a wiring fault
could energize the cases of 3 prong devices connected
to other outlets.  Be sure, though, that there aren't
indirect ground plug connections, such as via the sheath
on BX cable.
The CEC permits you to replace a two prong receptacle with a three
prong if you fill the U ground with a non-conducting goop.
Like caulking compound.  This is not permitted in the NEC.
Subject: Are you sure about GFCIs and ungrounded outlets?
Should the test button work?
We're sure about what the NEC and CEC say.  Remember, though,
that your local codes may vary.  As for the TEST button -- there's
a resistor connecting the LOAD side of the hot wire to the LINE
side of the neutral wire when you press the TEST button.  Current
through this resistor shows up as an imbalance, and trips the GFCI.
This is a simple, passive, and reliable test, and doesn't require
a real ground to work.  If your GFCI does not trip when you press
the TEST button, it is very probably defective or miswired.  Again:
if the test button doesn't work, something's broken, and potentially
dangerous.  The problem should be corrected immediately.
The instructions that come with some GFCIs specify that the ground
wire must be connected.  We do not know why they say this.  The
causes may be as mundane as an old instruction sheet, or with the
formalities of UL or CSA listing -- perhaps the device was never
tested without the ground wire being connected.  On the other hand,
UL or CSA approval should only have been granted if the device
behaves properly in *all* listed applications, including ungrounded
outlet replacement.  (One of us called Leviton; their GFCIs are
labeled for installation on grounded circuits only.  The technician
was surprised to see that; he agreed that the NEC does not require
it, and promised to investigate.)
Subject: How should I wire my shop?
As with any other kind of wiring, you need enough power for all
devices that will be on simultaneously.  The code specifies
that you should stay under 80% of the nominal capacity of the
circuit.  For typical home shop use, this means one circuit for
the major power tools, and possibly one for a dust collector or
shop vac.  Use at least 12 gauge wire -- many power tools have
big motors, with a big start-up surge.  If you can, use 20 amp
breakers (NEC), though CEC requires standard 20A receptacles
which means you'd have to "replug" all your equipment.  Lights
should either be on a circuit of their own -- and not shared
with circuits in the rest of the house -- or be on at least two
separate circuits.  The idea is that you want to avoid a
situation where a blade is still spinning at several thousand
RPM, while you're groping in the dark for the OFF switch.
Do install lots of outlets.  It's easier to install them in the
beginning, when you don't have to cut into an existing cable.
It's useful if at least two circuits are accessible at each
point, so you can run a shop vac or a compressor at the same
time as the tool you really want.  But use metal boxes and
plates, and maybe even metal-sheathed cable; you may have
objects flying around at high speeds if something goes a bit
wrong.
Note that some jurisdictions have a "no horizontal wiring"
rule in workshops or other unfinished areas that are used
for working.  What this means is that all wiring must be
run along structural members.  Ie: stapled to studs.
Other possible shop circuits include heater circuits, 220V
circuits for some large tools, and air compressor circuits.
Don't overload circuits, and don't use extension cords if you
can help it, unless they're rated for high currents.  (A coiled
extension cord is not as safe as a straight length of wire of
the same gauge.  Also, the insulation won't withstand as much
heat, and heat dissipation is the critical issue.)
If your shop is located at some remove from your main panel,
you should probably install a subpanel, and derive your shop
wiring from it.  If you have young children, you may want to
equip this panel with a cut-off switch, and possibly a lock.
If you want to install individual switches to ``safe''
particular circuits, make sure you get ones rated high enough.
For example, ordinary light switches are not safely able to
handle the start-up surge generated by a table saw.  Buy
``horsepower-rated'' switches instead.
Finally, note that most home shops are in garages or unfinished
basements; hence the NEC requirements for GFCIs apply.  And
even if you ``know'' that you'd never use one of your shop
outlets to run a lawn mower, the next owner of your house might
have a different idea.
Note: Fine Woodworking magazine often carries articles on shop
wiring.  April 1992 is one place to start.
Subject: Underground Wiring
You will need to prepare a trench to specifications, use
special wire, protect the wire with conduit or special plastic
tubing and possibly lumber (don't use creosoted lumber, it rots
thermoplastic insulation and acts as a catalyst in the corrosion
of lead).  The transition from in-house to underground wire is
generally via conduit.  All outdoor boxes must be specifically
listed for the purpose, and contain the appropriate gaskets,
fittings, etc.  If the location of the box is subject to immersion
in water, a more serious style of water-proof box is needed.  And
of course, don't forget the GFCIs.
The required depths and other details vary from jurisdiction to
jurisdiction, so we suggest you consult your inspector about
your specific situation.
A hint: buy a roll of bright yellow tape that says "buried power
line" and bury it a few inches above where the wire has been placed.
Subject: Aluminum wiring
During the 1970's, aluminum (instead of copper) wiring became
quite popular and was extensively used.  Since that time,
aluminum wiring has been implicated in a number of house fires,
and most jurisdictions no longer permit it in new installations.
We recommend, even if you're allowed to, that do not use it for new
wiring.
But don't panic if your house has aluminum wiring.  Aluminum
wiring, when properly installed, can be just as safe as copper.
Aluminum wiring is, however, very unforgiving of improper
installation.  We will cover a bit of the theory behind potential
problems, and what you can do to make your wiring safe.
The main problem with aluminum wiring is a phenomenon known as
"cold creep".  When aluminum wiring warms up, it expands.  When
it cools down, it contracts.  Unlike copper, when aluminum goes
through a number of warm/cool cycles it loses a bit of tightness each
time.  To make the problem worse, aluminum oxidises, or corrodes
when in contact with certain types of metal, so the resistance
of the connection goes up.  Which causes it to heat up and corrode/
oxidize still more.  Eventually the wire may start getting very hot,
melt the insulation or fixture it's attached to, and possibly even
cause a fire.
Since people usually encounter aluminum wiring when they move
into a house built during the 70's, we will cover basic points of
safe aluminum wiring.  We suggest that, if you're considering purchasing
a home with aluminum wiring, or have discovered it later, that you
hire a licensed electrician or inspector to check over the wiring
for the following things:
1) Fixtures (eg: outlets and switches) directly attached to
aluminum wiring should be rated for it.  The device will
be stamped with "Al/Cu" or "CO/ALR".  The latter supersedes
the former, but both are safe.   These fixtures are somewhat
more expensive than the ordinary ones.
2) Wires should be properly connected (at least 3/4 way around
the screw in a clockwise direction).  Connections should be
tight.  While repeated tightening of the screws can make the
problem worse, during the inspection it would pay off to snug
up each connection.
Note that aluminum wiring is still often used for the
main service entrance cable.  It should be inspected.
3) "push-in" terminals are an extreme hazard with aluminum wire.
Any connections using push-in terminals should be redone with
the proper screw connections immediately.
4) There should be no signs of overheating: darkened connections,
melted insulation, or "baked" fixtures.  Any such damage should
be repaired.
5) Connections between aluminum and copper wire need to be
handled specially.  Current Canadian codes require that the
wire nut used must be specially marked for connecting
aluminum to copper.  The NEC requires that the wire be
connected together using special crimp devices, with an
anti-oxidant grease.  The tools and materials for the latter
are quite expensive - not practical to do it yourself unless
you can rent the tool.
6) Any non-rated receptacle can be connected to aluminum wiring
by means of a short copper "pigtail".  See (5) above.
7) Shows reasonable workmanship: neat wiring, properly stripped
(not nicked) wire etc.
If, when considering purchasing a home, an inspection of the wiring
shows no problems or only one or two, we believe that you can consider
the wiring safe.  If there are signs of problems in many places,
we suggest you look elsewhere.  If the wrong receptacles are used,
you can replace them with the proper type, or use pigtails - having
this professionally done can range from $3 to $10 per receptacle/switch.
You can do this yourself too.
Subject: I'm buying a house!  What should I do?
Congratulations.  But...  It's generally a good idea to hire
an inspector to look through the house for hidden gotchas.
Not just for wiring, but plumbing and structural as well.  If an
inspection of the wiring shows no problems or only one or two minor
ones, we believe that you can consider the wiring safe (after any
minor problems are fixed).  If there are signs of problems in many
places, we suggest you look elsewhere.
Here's some hints on what to look for:
Obvious non-code wiring can include:
- Zip cord wiring, either concealed or nailed to walls
- Hot wiring on the identified (neutral) conductor without
proper marking.
- Ungrounded grounding outlets (except when downstream of
a GFCI)
- Splices hanging in mid-air (other than proper knob-and-tube)
- Switched neutrals
- Unsecured Romex swinging about like grapevines
Certain wiring practises that are actually to code (or were at one
time) sometimes reveal DIY wiring that may have hidden violations:
- Switches that seem to control nothing (abandoned, perhaps
not properly terminated wiring)
- A wall switch that shuts off a group of lights that are
separately controlled by other wall switches.  (except when
it's *really* convenient ;-)
- Switches and outlets in bizarre locations
- Great numbers of junction boxes without outlets or lamps
- Junction boxes with great numbers of wires going into them
- Wiring that passes through a closet instead of a wall or
ceiling
- Backwrapped grounding wires
Subject: What is this weird stuff?  Old style wiring
In the years since Edison "invented" electricity, several different
wiring "styles" have come and gone.  When you buy an older home you
may encounter some of this stuff.  This section describes the old
methods, and some of their idiosyncrasies.
The oldest wiring system you're likely to encounter is called
"knob and tube" (K&T).  It is made up of individual conductors with
a cloth insulation.  The wires are run along side structural
members (eg: joists or studs) using ceramic stand-offs (knobs).
Wire is run through structural members using ceramic tubes.  Connections
were made by twisting the wire together, soldering, and wrapping
with tape.  Since the hot and neutral were run separately,
the wiring tends to be rather confusing.  A neutral often runs
down the centre of each room, with "taps" off to each fixture.
The hot wire tended to run from one fixture to the next.  In some
cases K&T isn't colour-coded, so the neutral is often the same
colour as the hot wires.
You'll see K&T in homes built as late as the 40's.
Comments on K&T:
- the people installing K&T were pretty paranoid about
electricity, so the workmanship tends to be pretty good.
- The wire, insulation and insulators tend to stand up
very well.  Most K&T I've seen, for example, is in
quite good condition.
- No grounding.  Grounding is usually difficult to install.
- boxes are small.  Receptacle replacement (particularly with
GFCI) can be difficult.  No bushing on boxes either,
so wiring changes need special attention to box entry.
- Sometimes the neutral isn't balanced very well between
separately hot circuits, so it is sometimes possible to
overload the neutral without exceeding the fusing on
any circuit.
- Building code does not permit insulation in walls
that contain K&T.
- Connection to existing K&T from new circuits can be
tricky.  Consult your inspector.
- Modern wiring practise requires considerably more
outlets to be installed than K&T systems did.
Since K&T tends to be in pretty decent condition it generally isn't
necessary to replace it simply because it's K&T.  What you should
watch out for is renovations that have interfered with it and
be cautious about circuit loading.  In many cases it's perfectly
reasonable to leave existing K&T alone, and add new fixtures on
new circuits using modern techniques.
After K&T, they invented multi-conductor cable.  The first type
you will see is roughly a cloth and varnish insulation.  It looks
much like the romex cable of the last decade or two.  This stuff was
used in the 40's and 50's.  Again, no grounding conductor.
It was installed much like modern wiring.  Its major drawback
is that this type of insulation embrittles.  We've seen whole
systems where the insulation would fracture and fall off at
a touch.  BX cable of the same vintage has similar problems.
This stuff is very fragile, and becomes rather hazardous if
the wires become bare.  This wiring should be left untouched as
much as possible - whenever an opportunity arises, replace it.
A simple receptacle or switch replacement can turn into a several
hour long frustrating fight with electrical tape or heat-shrink
tubing.
After this wiring technique, the more modern romex was invented.
It's almost a asphalt impregnated cloth.  Often a bit sticky.
This stuff stands up reasonably well and doesn't present a hazard
and is reasonably easy to work with.  It does not need to be
replaced - it should be considered as safe as the "modern" stuff -
thermoplastic insulation wire.  Just don't abuse it too much.
Subject: Where do I buy stuff?
Try to find a proper electrical supply outlet near you.  Their
prices will often be considerably better than chain hardware stores or
DIY centres, have better quality materials, have wider variety
including the "odd" stuff, and have people behind the counter that
know what you're talking about.  Cultivate friendly knowledgeable
sales people.  They'll give you much valuable information.
--
Chris Lewis; clewis@ferret.ocunix.on.ca; Phone: Canada 613 832-0541
Psroff 3.0 info: psroff-request@ferret.ocunix.on.ca
Ferret list: ferret-request@ferret.ocunix.on.ca
From: smckinty@sunicnc.France.Sun.COM (Steve McKinty - SunConnect ICNC)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: SunConnect
Lines: 26
Distribution: world
NNTP-Posting-Host: hardy.france.sun.com
Keywords: Nuclear
In article <1qlg9o$d7q@sequoia.ccsd.uts.EDU.AU>, swalker@uts.EDU.AU (-s87271077-s.walker-man-50-) writes:
>
>
> I really don't know where to post this question so I figured that
> this board would be most appropriate.
> I was wondering about those massive concrete cylinders that
> are ever present at nuclear poer sites. They look like cylinders
> that have been pinched in the middle. Does anybody know what the
> actual purpose of those things are?. I hear that they're called
> 'Cooling Towers' but what the heck do they cool?
Water. Nuclear stations don't generate electricity directly from the
reactor, they use the reactor to generate heat. The heat is then used to
heat water just as in a conventional oil or coal station, and the
resultant steam drives the turbines.
The cooling towers are used to cool the steam and recondense it into water
to continue the cycle
Steve
--
Steve McKinty
Sun Microsystems ICNC
38240 Meylan, France
email: smckinty@france.sun.com	   BIX: smckinty
From: markz@ssc.com (Mark Zenier)
Subject: Re: Trace size for a 15 Amp supply
Organization: SSC, Inc.,  Seattle, WA
X-Newsreader: TIN [version 1.1 PL6]
Lines: 12
R.G. Keen (rg@futserv.austin.ibm.com) wrote:
: A quick and dirty way to get higher current carrying capacity
: on PC board traces for one- or few-of-a-kind boards is to
: strip some #14 Romex house wiring cable to bare copper, form
: the bare copper to follow the trace, and solder it down.
And if it's not quick and dirty, you can get bus bars that
are stamped out with leads that insert in the PC board.
Mark Zenier  markz@ssc.wa.com  markz@ssc.com
From: craig@toontown.ColumbiaSC.NCR.COM (Craig S. Williamson)
Subject: Re: Looking for a good Spice book
Article-I.D.: toontown.627
Reply-To: craig@toontown.ColumbiaSC.NCR.COM (Craig S. Williamson)
Organization: NCR E&M Columbia, SC
Lines: 17
In article <canright.734829385@convex.com> canright@convex.com (Robert Canright) writes:
|you might try
|"Computer-Aided Circuit Analysis Using SPICE" by Walter Banzhaf,
|at bookstores, paperback, ~$33, lots of examples. Dr. Banzhaf
|is a teacher.
Is there another book.  I have this one and don't find it helpfull in
learning Spice.  It would make a good reference book but I found it lacking
for learning Spice.  Are there any others?
Craig
--
"You took the bull by the horns
-Craig Williamson                              and stepped in something good."
Craig.Williamson@ColumbiaSC.NCR.COM               - Balki Bartokomas
craig@toontown.ColumbiaSC.NCR.COM (home)                 Perfect Strangers
From: heke@stekt.oulu.fi (Heikki Paananen)
Subject: Re: How do DI boxes work?
In-Reply-To: lancer@oconnor.WPI.EDU's message of 15 Apr 93 15:02:28
Lines: 38
Organization: University of Oulu, Dept. of EE, Finland
In article <LANCER.93Apr15150228@oconnor.WPI.EDU> lancer@oconnor.WPI.EDU (Stephe Lewis Foskett) writes:
>   I'm doing sound for a couple of bands around here and we need Direct
>   Input boxes for the keyboards.  These are the little boxes that take a
>   line level out of the keyboard and transform it into low-Z for the run
>   to the mixer.  Sadly they cost like $50 (or more) each and I'm going
>   to need like 5 or 10 of them!  I looked inside one (belonging to
>   another band) and it looks like just a transformer.  Does anyone have
>   any plans for building them?  Perhaps in Anderton's "Electronic
>   Projects for Musicians" book (which I am having a hell of a time
>   tracking down...)?
An Easy way to solve the problem is to use two op-amps to form the
balanced low-Z output, but this solution does not provide any
galvanic isolation between keyboard (or whatever plugged) and
mixer. If no tight requiremets are demanded and some hum, snap,
crackle and pop sounds (formed by ground loops) can be tolerated,
the op-amp solution is just what you are looking for! (It is
cheap...somewhat $10/DI-box).
Not sure, but Craig Anderton did introduce one DI-box project
in Guitar Player mag years ago (transformerless).....
>   Thanks a lot!
Hope this helps. Email, if more details wanted....
>   - lancer@wpi.wpi.edu -                    - 0{{  MoDiMiDoFrSaSo: -
>   -   Mein Kopf ist ein Labyrinth, mein Leben ist ein Minenfeld    -
-----------------------------------------------------------------------
Heikki Paananen                           heke@stekt.oulu.fi
The University of Oulu
Department of electrical engineering      -Just a student
Finland
-----------------------------------------------------------------------
Home is where the heart lies,
but if the heart lies where is home?
-Fish
From: cmh@eng.cam.ac.uk (C.M. Hicks)
Subject: Re: How do DI boxes work?
Organization: cam.eng
Lines: 36
Nntp-Posting-Host: tw100.eng.cam.ac.uk
lancer@oconnor.WPI.EDU (Stephe Lewis Foskett) writes:
>I'm doing sound for a couple of bands around here and we need Direct
>Input boxes for the keyboards.  These are the little boxes that take a
>line level out of the keyboard and transform it into low-Z for the run
>to the mixer.  Sadly they cost like $50 (or more) each and I'm going
This is indeed one function, but more sophisticated ones do level control
and ground-lift (separating the keyboard and mixer earths) aswell.
>to need like 5 or 10 of them!  I looked inside one (belonging to
>another band) and it looks like just a transformer.  Does anyone have
Simple ones are just that - a transformer. A decent quality audio trans-
former will cost most of that $50. They are wired thus...
HOT   --------------|  |----------------- HOT
)||(
Input from            )||(                Balanced out to mixer
Keyboard              )||(
|  |----------------- COLD
|
GND   --------------|-------------------- GND
The ground-lift switch disconnects the GND line from the mixer. The
transformer ratio depends on the precise application, but around 10:1
turns ratio may be a good place to start.
Christopher
--
==============================================================================
Christopher Hicks    |      Paradise is a Linear Gaussian World
cmh@uk.ac.cam.eng    |    (also reported to taste hot and sweaty)
==============================================================================
From: cmh@eng.cam.ac.uk (C.M. Hicks)
Subject: Re: MICROPHONE PRE-AMP/LOW NOISE/PHANTOM POWERED
Organization: cam.eng
Lines: 22
Nntp-Posting-Host: tw100.eng.cam.ac.uk
davidj@rahul.net (David Josephson) writes:
>In <C5JJJ2.1tF@cmcl2.nyu.edu> ali@cns.nyu.edu (Alan Macaluso) writes:
>>I'm looking to build a microphone preamp that has very good low-noise characteristics,  large clean gain, and incorportates phantom power (20-48 volts (dc)) for a PZM microphone.  I'm leaning towards a good, low-cost (??) instrumentation amplifier to maintain the balanced input from the microphone, for its good CMRR, internal compensation, and because i can use a minimal # of parts.
>>Does anyone out there have any experience, suggestions, advice, etc...that they'd like to pass on, I'd greatly appreciate it.
>Without doing anything really tricky, the best I've seen is the
>Burr-Brown INA103. Their databook shows a good application of this
>chip as a phantom power mic pre.
I've had very good results from the SSM2016 from PMI (part of Analogue
Devices). They have also now introduced the SSM2017 which looks good on
paper, but which I haven't tried yet.
Christopher
--
==============================================================================
Christopher Hicks    |      Paradise is a Linear Gaussian World
cmh@uk.ac.cam.eng    |    (also reported to taste hot and sweaty)
==============================================================================
From: dwo@zerberus.gud.siemens.co.at (F.Dwo)
Subject: DSP 56001
Nntp-Posting-Host: zerberus.gud.siemens-austria
Organization: Siemens AG Oesterreich
Lines: 15
Hi !!!
Is there somebody using a 56001 DSP from Motorola ???
I am searching for programms concerning audio effects.
I built a 4 channel mixer (4ADC + 1DSP) for audio signals.
I built some digital filters and echos, but now i want to
include some effects like HARMONIC Equalizer or chorus.
The problem is, I dont know how these effects work (so I cant
write a programm).
So if someone has programms or just knows how such effects work,
please contact me in the newsgroup or via e-mail.
(Also if there are books about this problem)
Thanks in advance
(DWO)
Subject: Re: Cable TVI interference
From: ganter@ifi.unibas.ch (Robert Ganter)
Organization: Institut fuer Informatik
Nntp-Posting-Host: schroeder.ifi.unibas.ch
Lines: 56
In article <1qevrf$4t@hpscit.sc.hp.com>  writes:
>
> As is typical nowadaze, you will probably have to do somebody else's job
> for them. Although this shouldn't be needed, you might take a few minutes
> to wander around the neighborhood with an HT sniffing for cable leakage
> on your freq. after shutting down your system for a while.
>
> If you are fortunate enough to the find the hole, call the cable company and
> get the highest link in the chain of command you can. Explain the problem,
> whose job it really is to maintain THEIR equipment, and how much of a nice
> guy you are to have tracked down THEIR problem for them.
>
> You may have been lucky and made a new contact that could be helpful in the
> future.
>
> You should always try the 'honey' approach before bringing out the
> Jack Nicholson impressions.....  >:-)
>
> This has worked for me in the past with the power company when tring to
> find loose/noisy high voltage lines/hardware. Only once did I have to
> tell them I was narrowing the problem down to a specific pole by bumping
> a whole line of poles with my car. Got 'em out there THAT NIGHT. And, they
> didn't have to meet Jack!
>
> As a disclaimer, THEIR method for finding loose hardware was usually
> whacking the poles with a huge sledgehammer after their high tech arc-
> finding 'scope couldn't find the problem.
>
>
>
> Bill
> wb6 rotten zucchini garden
Here in switzerland, the situation is exactly the same. The cable tv companies
even tried to stop amateur radio in switzerland in the beginning of cable
tv(they seem to be too stupid to know anything about international frequency
conferences or so). Even today, they use the cheapest possible coax running
into problems they can't solve anymore. As Bill noted, the only way is to look
for a solution with the neighbours *BEFORE* calling for the cable tv guys or
the fcc. The chance to find neighbours with some sense for reason is by far
bigger than with these people (especially the first ones). As anywhere in an
administration people don't like, if You tell them to work for the money they
get...
The problem is, that radio amateurs don't have the power to put trough their
rights in all cases. So let's hope they start soon with optical fibers and get
out of our freqencies.
Cheers   Robert  (HB9NBY)
--
Robert Ganter			/------------\
Universitaet Basel		| I am a fan |
Institut fuer Informatik	| of my plan |
Basel/Switzerland		\------------/
ganter@ifi.unibas.ch
amateurradio: HB9NBY	packet: HB9NBY@HB9EAS.CHE.EU
From: mkaschke@oasys.dt.navy.mil (Martin Kaschke)
Subject: 4-Band Equalizer
Reply-To: mkaschke@oasys.dt.navy.mil (Martin Kaschke)
Organization: Carderock Division, NSWC, Bethesda, MD
Lines: 15
I was wondering if anyone out there in net-land knew of a SIMPLE
way to make a 4-band equalizer (single channel).  I need it to accept
LINE inputs (tape deck, CD player, etc.) and output to the same! So
input impedance should equal output impedance.  Also, since I am driving
a line, I would need 1 volt p-p output.  Final requirement is that I
can either:
1. Control it digitally
OR
2. Control it easily, or with few resistors
FINALLY - If anyone knows of any FILTER or EQUALIZER chips, that might
be useful, please let me know. (I have seen a couple of them from NATIONAL,
and MAXIM).  Thanks in advance,
Martin
From: Arthur_Noguerola@vos.stratus.com
Subject: Re: Adcom cheap products?
Organization: Stratus Computer, Marlboro Ma.
Lines: 22
NNTP-Posting-Host: m21.eng.stratus.com
In article <C5K177.BoK@world.std.com> rogerw@world.std.com (Roger A Williams) wrote:
>mdonahue@amiganet.chi.il.us (Mike Donahue) writes:
>
>
>>I do NOT know much about Adcom Mobil Audio products, but I DO know for a fact
>>that ADCOM does NOT make its own "High End" Home Audio Equptment and that 80%+
>>of it comes directly out of Tiawan...
>
>Like most high-volume manufacturers, Adcom has most of its PC boards
>assembled off-shore (in their case, mostly in the far east).  Final
>assembly _and testing_ are done in East Brunswick.
>
and of course you older folks on the net will remember
way back when Adcom got its RAVE reviews and kudos (ca
1985  or  so)  their  555 amp and preamp WERE not only
designed here but built here in  the  USA.  then  they
went  to  mexico  and then to taiwan right after their
sales  skyrocketed   because   of   their   Stereopile
review!!!  if you have units that old look for MADE IN
--- stickers on your unit.
From: baldur@rsp.is (Baldur Thorgilsson)
Subject: receiver system
Summary: multi channel receiver system?
Keywords: telemetry, receiver system
Organization: National Hospitals, Iceland
Lines: 19
Dear Netters
I want to send EMG-signals from a running person to a computer.
Each signal is 4KHz wide and there is up to 30 of them on each
running person. The signal is only to be sent over a few hundred
meters. It seems to me that the frequency intended for this use is
about 150MHz and about 440MHz.
To make the transmitters as light as possible I suppose it will be best
the to send the signals in an analog form. As this application is rather
specialized I do not expect to be able to buy the exact transmitter-
units i need.
On the other hand I imagine that I can buy the receiver somewhere. I
need a multichannel (up to 30 channels) receiver or 30 complete
receivers in some rack system where one can add as many receivers
as needed in the particular case.
DO ANYBODY KNOW IF THERE IS EXISTING SUCH RECEIVER
SYSTEM ON THE MARKET?
baldur@rsp.is     (TF3BP) (please respond by email rather than nn)
From: then@snakemail.hut.fi (Tomi  H Engdahl)
Subject: Re: Telephone on hook/off hok ok circuit ~
Organization: Helsinki University of Technology, Finland
Lines: 17
<laird.734044906@pasture.ecn.purdue.edu>
<1ptolq$p7e@werple.apana.org.au>
NNTP-Posting-Host: lk-hp-11.hut.fi
In-reply-to: petert@zikzak.apana.org.au's message of 7 Apr 1993 05:26:18 GMT
In article <1ptolq$p7e@werple.apana.org.au> petert@zikzak.apana.org.au (Peter T.) writes:
>Since an on-hook line is aprox 48-50V, and off-hook it usually drops below 10V.
>How about an LED in series with a zener say around 30V.
>On-hook = LED on
>Off-hook = LED off.
>Would this work? If anyone tries/tried it, please let me know.
Not recommended. Your circuit would take too much current, when
telephone is on-hook. Telephone company does not like it.
--
Tomi.Engdahl@hut.fi  !  LOWERY'S LAW:
then@niksula.hut.fi  !  "If it jams - force it. If it breaks,
!   it needed replacing anyway."
* This text is provided "as is" without any express or implied warranty *
From: webb@itu1 (90-29265  Webber  AH)
Subject: Re: Adcom cheap products?
Article-I.D.: hippo.1993Apr16.105738.20864
Organization: Rhodes University, Grahamstown, South Africa
Lines: 44
X-Newsreader: TIN [version 1.1 PL8]
: >I want to upgrade my system and was thinking of buying Adcom seperates.
: >I have heard from alot of people, though, that Adcom sounds great but
: >that the components are made cheaply and therefore won't last very long.
: >The time estimates I've heard are like only 3 or 4 years.  Is this true?
I own the Adcom 60W power amp.  As far as I'm concerned, there's no
amp which can touch it at the price range.
The build quality is very impressive and is far superior to other
amps in the price range.  The whole amplifier is extremely solid
with massive heat sinks and very solid casing.
If you open the amp up, there are only very good quality components
in and the amp seems to be designed extremely well.  Perfect
symmetry for both channels and TWO transformers - one for each
channel.  The binding posts on the back of the amplifier are
virtually the same as those on the Classe model 70 ie. very good.
I was also sceptical about the amps being built in the far-east
or where-ever.  But if you look in the amp and see what components
they use and how it was designed, you can easily see why the
amplifiers sound so brilliant.
I cannot see why people say the amplifier won't last - not with
those quality components inside.  Sure the amp runs very fairly
hot - but that's how you get an amp to sound incredibly good.
My last point, I recently auditioned the Adcom preamp something like
the 545 or something.  It was two years old and it still sounded
like new.
If you build an amplifier decently, like the Adcom's, they will
sound brilliant and last a long time - period.
Just my thoughts, but then - I do own one of Adcom's amps.
--
***********************************************************************
**    Alan Webber                                                    **
**                      webb@itu1.sun.ac.za                          **
**                      webb@itu2.sun.ac.za                          **
**                                                                   **
** The path you tread is narrow and the drop is sheer and very high  **
** The ravens all are watching from a vantage point near by          **
** Apprehension creeping like a choo-train up your spine             **
** Will the tightrope reach the end; will the final couplet rhyme    **
***********************************************************************
From: mabbot@stellenbos.csir.co.za (Mike Abbot)
Subject: High level language compilers for uControllers ?
Article-I.D.: stellenb.mabbot.30.0
Organization: CSIR
Lines: 15
NNTP-Posting-Host: 146.64.23.16
X-Disclaimer: None of the opions expressed herein are the official
X-Disclaimer: opinions of the CSIR or any of its subsidiaries.
X-Disclaimer: **  So don't freak out at _us_ about anything  **
Howdy chaps
Has anybody got any pointers to good C, Pascal, etc compilers for
microcontrollers, shareware or otherwise ?
My specific need is for 8051 C, but if the responses are many and varied I
will post a summary.
Cheers
Mike
Mike Abbott	mabbot@stellenbos.csir.co.za
Cape Town	mabbot@fred.csir.co.za
South Africa
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: Illusion
Organization: Northeastern Ohio Universities College of Medicine
Lines: 31
I missed the first article[s] on this line due to not having a
chance to read the news for a couple of days...
The idea is commercialized in at least one product, the Private
Eye.  That's a small cube-shaped device that the user straps around
the head similar to a sweat band.  There is a boom that comes from
the side on which the device is mounted so that it is positioned
in front of the user's eye.
The Private Eye we had here for evaluation was Hercules-MDA
compatible.  The innards are a row (~400 LEDs) that are swept up
and down by a galvonometer-like movement.  The result is that the
sweeping LED bar forms a fused raster.  There is a virtual image
projected in front of the user that the visual system tends to fuse
with the background.
I didn't like the device very much.  I found it easiest to use if I
looked at a blank white wall.  I had problems with focus tracking
if I glanced down to look at my keyboard for an out-of-the-way key.
The unit also emitted a soft buzz and vibration which I found
annoying.  Some people didn't seem to mind the buzz.  Properly
used, however, the image clarity was quite crisp.
I don't know if the company has taken the technology any further in
the last year or two, but it did seem to have promise.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: Michael_LaBella@vos.stratus.com
Subject: Re: Adcom cheap products?
Organization: Stratus Computer, Marlboro Ma.
Lines: 20
NNTP-Posting-Host: m3-enet.eng.stratus.com
>Off-shore assembly is one reason that Adcom is able to make products
>that perform as well as those from people like Audio Research and Van
>Alstine (and better than Hafler and Forte'), but at a much lower cost.
How do you spell "tuna helper" ?
I gather by off-shore assembly you mean that adcoms are built by
blue-fin tuna's who are into that squid-fi sound?  (I agree on that one).
My Adcom 555 preamp did sound better after installing the famous
"running the chips class "A" resistor mod", and replacing the metal
bottom cover with plexiglass,, too bad the factory could not make em sound
better,, but better sound, unfortunately, does not appear to be a priority
with Adcom, else the mods would neither have been necessary, nor would they
have improved what was already touted as superlative state-o-d-art le'sound.
I really want to hear from all those people out there who have traded up
from an sp9II (even an sp3a!) to a GFP-555/etc., or maybe from those that
have dumped their forte' amps for a GFA-555/etc....
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: Adcom cheap products?
Organization: Northeastern Ohio Universities College of Medicine
Lines: 23
I have an Adcom GFA-555 that I got in 1985.  There certainly isn't
anything magic about it.  The components used are decent, but
nothing uncommon with respect to consumer grade components.
The GFA-555 is a nice piece of equipment.  I'm glad that Adcom had
the guts to not over-do the packaging.  It irks me when I see
audiophile oriented equipment whose case and heat sinks probably
cost much more and receive more attention than the electronics they
are supposed to serve.
I don't see any big deal about the geographic region in which
something is assembled.  This is especially true for something as
low-technology as a GFA-555.
I'd hope that a GFA-545 would still work well after several years.
Except under conditions of extreme abuse, there isn't much there to
go wrong.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
Subject: Re: Can Microwaves Be Used To Collect XYZ Coordinates
From: ganter@ifi.unibas.ch (Robert Ganter)
Organization: Institut fuer Informatik
Nntp-Posting-Host: schroeder.ifi.unibas.ch
Lines: 63
In article <1993Apr15.103953.66252@cc.usu.edu>  writes:
> In article <C5Hs5J.AG7@bcstec.ca.boeing.com>, rgc3679@bcstec.ca.boeing.com
(Robert G. Carpenter) writes:
>
> |> It seems reasonable to me that a microwave transmitter-receiver setup
could
> |> do the job. For example, say you want to map an acre lot, it'd be
convenient
> |> to place MW transmitters around the lot's periphery (either 2 or 3) and
then
> |> carry a hand-held recorder and walk to a point on the lot, press a button
and
> |> the coords of the recorder's location is stored as digital data.
> |>
> |> What's the chance of this working? Any systems like this already exist?
> |> What kind of accuracy could you expect? What would something like this
> |> cost to prototype? Is there a better alternative than microwaves?
>
> Of course you could develope this system, but there is already a system
called Global
> Positioning Satellites.  It gives three dimensional coordinates anywhere on
earth.
> Many surveyors use this system with a differential receiver/transmitter to
get
> coordinates within centimeters.  Basic receivers with resolution of a few
meters (on
> a good day) are available from many sources.
>
>
> --
> WMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMWMW
>
>   \_      \_  \_\_\_    \_\_\_               Weston R Beal
>    \_      \_  \_    \_  \_    \_         sldf3@sol.ee.usu.edu
>     \_  \_  \_  \_\_\_    \_\_\_            sldf3@cc.usu.edu
>      \_\_  \_\_  \_  \_    \_    \_       Electrical Engineer
>       \_      \_  \_    \_  \_\_\_       Utah State University
>
>   "That's the wonderful thing about crayons; they can take you to
>    more places than a starship can."    - Guinon
>
>
Thought it means Global Positioning System. There are two precision levels, one
for army applications (killing has to be very accurate today) and one for civil
ones. The civil precision is about 20 to 30m (correct me, if I'm wrong),
though, it may be insufficiant for mapping buildings. But there is a way with
an additional reference point (e.g. one fixed GPS system in a house) to get the
same high precision as the military version, but it gets pretty complicated
then. If You use a microwave system (actually this means some type of radar),
You need quite a lot of number crunching to get accurate vectorized data out of
Your original signals. So the GPS system seems to be the better (and running)
idea for Your application(there have been discussions in this newsgroup, don't
know of an address anymore).
Cheers    Robert   (HB9NBY)
--
Robert Ganter			/------------\
Universitaet Basel		| I am a fan |
Institut fuer Informatik	| of my plan |
Basel/Switzerland		\------------/
ganter@ifi.unibas.ch
amateurradio: HB9NBY	packet: HB9NBY@HB9EAS.CHE.EU
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: mysterious TV problem -- source?
Organization: Northeastern Ohio Universities College of Medicine
Lines: 19
If the set is direct line powered, try checking the [likely to be
there] hybrid regulator module down stream from the 170 volt
supply.  Several sets I've looked at use a 135 volt regulator.  The
regulators have a tendency to short out, making the safety circuits
shut down the EHT supply section.
Try putting the set on a Variac or adjustable transformer and lower
the AC input voltage to the set to about 90 volts.  If the set
operates nromally, then you know you've got a shorted regulator.
There are myriad other areas for problems, but I've seen the one
above several times.  Also, if the set uses one, the trippler
module may be shot; that's fairly common.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: larryhsu@mtl.mit.edu (Lawrence Hsu)
Subject: Shrunken monitor window?
Organization: MIT Microsystems Technology Laboratories
Lines: 12
NNTP-Posting-Host: mtl.mit.edu
Does anyone know what causes the ever-growing black border around the
edges of my computer screen?  The growth has been gradual so I don't
know how long it's taken to get this bad.  I have a 19" DEC (?)
color monitor, maybe five years old, and the black border is about 1.1
inches on the left and right sides, about 1.75 inches on the bottom and
negligible at the top of the screen.  The only controls are
brightness knob, contrast knob, deGauss switch, and power switch.
Is there anything to be done, or are the monitor's days numbered?
Larry Hsu
larryhsu@mtl.mit.edu
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: Dumb Question: Function Generator
Organization: Northeastern Ohio Universities College of Medicine
Lines: 36
1)  Output offset:  Obtain the service manual for the oscilloscope
and adjust the internal output offset contorl.  There is virtual
certainty that there is an internal ajustment for the offset
control's zero detent position.
2)  Verify that the function generator is properly loaded.  Many
generators expect you to supply a 50 ohm load.  Go to a hamfest
flea market and scrounge around for a pass-through 50 ohm
terminator that has a male and female BNC (or whatever) connector
on it.  The calibrator on my Tektronix scope is designed to put out
.4v into a 1 meg load, but .1 volt into a 50 ohm load.  You may
also find that loading the output of the function generator also
reduces the harmonic distortion.
Build an attenuator.  You don't have to use (and I wouldn't want to
use) the input impedance of the device under test as part of the
voltage divider to drop the input test voltage.  Consider this:
------10K--------+---------? ohm ----
|
Gen            50 ohm            D.U.T.
(loaded)         |
-----------------+-------------------
Think about the ratio of 50/10K and then think about the accuracy
to which you can read voltages on your oscilloscope.  You can
virtually discount the loading of the D.U.T.  Also you have the
millivolt test generator you want.
Good luck,
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: seema@madvlsi.columbia.edu (Seema Varma)
Subject: IC Packages
Organization: Columbia University
X-Posted-From: britain.madvlsi.columbia.edu
NNTP-Posting-Host: sol.ctr.columbia.edu
Lines: 28
Hi,
I am looking for some help in choosing a package
for a high-speed silicon ADC (100Mhz) currently being
fabricated. This is a PhD research project and I have to test
the chip at speed on a PCB. I expect to have roughly 100
packaged circuits and will do DC, low-speed and high-speed
testing using 3 different set-ups for the test chip.
I know for sure that a DIP will not work
(the long lead lines have too high an inductance).
Getting a custom-made package is too expensive, so
I am trying to choose between a flatpak and a
leadless chip carrier. The flatpack would be hard
to test since it has to be soldered on to the test
setup and I would spend loads of time soldering
as I kept changing the test chip. The leadless chip
carrier sockets also have long lead lines and may
not work at high speeds.
Does anyone out there have experience/knowledge
of this field ? I would greatly appreciate help! Any ideas/
names of companies manufacturing holders/sockets/packages
would help.
P.S. The multi-layer fancy GaAs packages seem like a bit
of overkill(?)
--- Seema Varma
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Keywords: Nuclear
Organization: Northeastern Ohio Universities College of Medicine
Lines: 25
Just to complete that thought, the cooling towers cool water that
circulates through heat exchangers that recondense the turbine
exhaust back into feedwater for the heat exchangers that transfer
energy from the reactor's cooling circuit.
|---------------|   |------turbine, etc---|  |---------|
|                >   >                    >   >        .
reactor            <   <                    <   >        .
|                >   >                    >   >        C. T.
|---------------|    |--------------------|  |----------
The reactor has a closed loop circuit to prevent radioactive
contamination of the the turbine feedwater.
The cooling tower is a separate circuit to avoide contamination of
the turbine feedwater with atmospheric contamininats, etc.
Purifying boiler feedwater is important business at both fossil
fired and nuclear generation facilities.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: jmains@engr.latech.edu (John P. Mains)
Subject: Electrical Properties of ELASTOMERS
Organization: Louisiana Tech University
Lines: 13
Distribution: usa
Reply-To: jmains@engr.latech.edu
NNTP-Posting-Host: altair.engr.latech.edu
Hello,
I am looking for carbon-doped rubber.    Or an highly elastic material that changes its resistivity, or some
other electrical property when streched.
If you could email me any info you may have on material names or companies that make the stuff
it would be highly appreaciated.
Thanx
JP
Biomedical Engineering
Louisiana Tech University
Subject: Re: Picking up cable tv with an aerial.
From: ganter@ifi.unibas.ch (Robert Ganter)
Organization: Institut fuer Informatik
Nntp-Posting-Host: schroeder.ifi.unibas.ch
Lines: 11
Great, the first advantage of cheap coax, I've ever heard.
Cheers   Robert  (HB9NBY)
--
Robert Ganter			/------------\
Universitaet Basel		| I am a fan |
Institut fuer Informatik	| of my plan |
Basel/Switzerland		\------------/
ganter@ifi.unibas.ch
amateurradio: HB9NBY	packet: HB9NBY@HB9EAS.CHE.EU
Subject: Re: What do Nuclear Site's Cooling Towers do?
From: ganter@ifi.unibas.ch (Robert Ganter)
Organization: Institut fuer Informatik
Nntp-Posting-Host: schroeder.ifi.unibas.ch
Lines: 34
In article <1qlg9o$d7q@sequoia.ccsd.uts.EDU.AU>  writes:
>
>
> I really don't know where to post this question so I figured that
> this board would be most appropriate.
> I was wondering about those massive concrete cylinders that
> are ever present at nuclear poer sites. They look like cylinders
> that have been pinched in the middle. Does anybody know what the
> actual purpose of those things are?. I hear that they're called
> 'Cooling Towers' but what the heck do they cool?
> I hope someone can help
>
This is definitely the wrong newsgroup for this, but never mind.
Any machine powered by heat (motor, steam- or gasturbine, steamengine,
thermoelement,etc) work the better, the bigger the temperature difference
between input and output is. Because You never get all thermic energy out of
the powering medium (steam, burning gaz, etc), You have to eliminate the rest
of the energy to keep the efficency high. A thermal electric power plant (coal,
oil or atomic power) works just the same way. You heat water (steam) to power
the turbine and generators. Because You don't get the whole energy out of the
steam (efficency is never 100%) You have to cool down this steam again by
something else. Most power plants use cooling towers for this purpose (some
type of mega-refrigerator...). Others use water of a river (ecologically not
unobjectionable). Got it ?
Cheers   Robert  (HB9NBY)
--
Robert Ganter			/------------\
Universitaet Basel		| I am a fan |
Institut fuer Informatik	| of my plan |
Basel/Switzerland		\------------/
ganter@ifi.unibas.ch
amateurradio: HB9NBY	packet: HB9NBY@HB9EAS.CHE.EU
From: gerald.belton@ozonehole.com (Gerald Belton)
Subject: Re: A question about 120V
Distribution: world
Organization: Ozone Online Operations, Inc., DBA The Ozone Hole BBS
Reply-To: gerald.belton@ozonehole.com (Gerald Belton)
Lines: 38
>>SO..  Here's my question.  It seems to me that I'd have the
>>same electrical circuit if I hooked the neutral jumper from the
>>neutral over to the ground screw on new 'three prong' grounding
>>outlets. What's wrong with my reasoning here?
>First, go to the local hardware store and pick up a copy of "Wiring
>Simplified" by H.L. Richter.  Now if your house is wired with metal
>conduit, you don't need a seperate ground wire (assuming the house
>is wired correctly and the pipes are connected to a cold water
>pipe in your basement).  The outlets that have a neutral hooked to
>the ground screw seem wrong.  Anyone else think so?
Back in the 70's I was a service technician for a cash register company.
The cash registers used microprocessor circuits and back then they were
VERY susceptible to electrostatic discharge and line noise.  The biggest
problems came from outlets that were not properly grounded.
In almost every place we went to do an installation, we found outlets
with the ground connected to the neutral.  For 99.9% of the things you
can plug into one of these, they work fine.  For our cash registers they
were a nightmare -- line noise tended to scramble the memory
periodically.
With modern electronics using switching power supplies this should be
less of a problem.  Even the company I used to work for is no longer
recommending a dedicated line with a seperate ground for their
equipment.  I imagine if you check MOST household wiring you will find
that the ground and neutral are connected.  Although not ideal, it
should be o.k. for most applications.
---
. SLMR 2.1 . My reality check just bounced.
----
The Ozone Hole BBS * A Private Bulletin Board Service * (504)891-3142
3 Full Service Nodes * USRobotics 16.8K bps * 10 Gigs * 100,000 Files
SKYDIVE New Orleans! * RIME Network Mail HUB * 500+ Usenet Newsgroups
Please route all questions or inquiries to:  postmaster@ozonehole.com
From: Mike Diack <mike-d@staff.tc.umn.edu>
Subject: Husky Programmer bits req'd
X-Xxdate: Sat, 17 Apr 93 04:10:01 GMT
Nntp-Posting-Host: dialup-slip-1-90.gw.umn.edu
Organization: persian cat & carpet co.
X-Useragent: Nuntius v1.1.1d7
Lines: 5
Help !! - I'm looking for a ISA driver card and driver software for a
Logical Devices Husky programmer (It aint mush good without these)
can anyone help with either of these items ?
cheers
Mike.
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: receiver system
Keywords: telemetry, receiver system
Organization: Northeastern Ohio Universities College of Medicine
Lines: 22
One thing to consider is time division multiplexing the EMG
channels to reduce the number of RF carriers you have to generate.
If you multiplexed the EMG inputs at 10KHz, that would probably be
sufficient for most physiology studies (you'd have ~ 330 Hz per
channel sampling rate.)  That level of analog multiplexing should
be rather easy to accomplish.
Combining a lot of RF carriers is pretty tricky to do without
generating intermodulation.  A system to be carried by a runner is
in a fairly harsh environment and would probably be difficult to
keep balanced.
A commercial hand-held transciever could probably be employed with
a little modification to accomodate widening the bandwidth.
Obviously, this has to be done in accordance with whatever laws
govern the use of transeivers in your location.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: cam@castle.ed.ac.uk (Chris Malcolm)
Subject: CASIO SF7500 SERIAL LINK
Organization: Edinburgh University
Lines: 8
The Casio 7500 lectric diary has a 3-wire serial interface with param
setting like RS232, for which one get a magic but expensive cable to
connect to a PC. Does anyone know the spec of this interface, e.g., it
needs inverting and boosting from CMOS signals to match RS232 lines?
--
Chris Malcolm    cam@uk.ac.ed.aifh          +44 (0)31 650 3085
Department of Artificial Intelligence,    Edinburgh University
5 Forrest Hill, Edinburgh, EH1 2QL, UK                DoD #205
From: garyg@warren.mentorg.com (Gary Gendel)
Subject: Re: A question about 120VAC outlet wiring.
Organization: Mentor Graphics Corp. -- IC Group
Lines: 42
Distribution: world
Reply-To: garyg@warren.mentorg.com
NNTP-Posting-Host: garyg.warren.mentorg.com
In article 1834@cmkrnl.com, jeh@cmkrnl.com writes:
>In article <1993Apr14.172145.27458@ecsvax.uncecs.edu>, crisp@ecsvax.uncecs.edu (Russ Crisp) writes:
>> SO..  Here's my question.  It seems to me that I'd have the
>> same electrical circuit if I hooked the jumper from the neutral
>> over to the ground screw on new 'three prong' grounding outlets.
>> What's wrong with my reasoning here?
>
>What you CAN do if you want three-prong outlets without additional wiring is
>to use a GFCI outlet (or breaker, but the outlet will be cheaper).  In fact,
>depending on where you are putting your new outlet(s), a GFCI may be *required*.
You still need to supply a proper ground for a Ground Fault Circuit Interrupter!
So rewiring is still a part of this job, however, the ground may be connected to
a local earth ground, rather than back at the breaker box.
As Jamie said, GFCI devices are required by code in a number of places, most
notably: bathrooms, and outside the house.  I do suggest the use of GFCI outlets,
rather than the breakers.  You will end up with much less headaches.  Noise pickup
in long cable runs is sometimes enough to cause frequent tripping of the breakers.
GFCI devices do save lives, if you decide to install them, be sure to check them
regularly (using the test button).
Running the family business (electrical supplies and lighting) for many years, I
have seen too many seasoned electricians fried, because they forgot to double check
their common sense list.  Please exercise caution.
---
Gary Gendel
Vice President:				Current consulting assignment:
Genashor Corp				Mentor Graphics Corporation
9 Piney Woods Drive			15 Independence Boulevard
Belle Mead, NJ 08502			Warren, NJ 07059
phone:	(908) 281-0164			phone:	(908) 604-0883
fax:	(908) 281-9607			email:	garyg@warren.mentorg.com
From: LLBGB@utxdp.dp.utexas.edu
Subject: chip / chipset for code 39 barcode?
Organization: UTexas Mail-to-News Gateway
Lines: 15
NNTP-Posting-Host: cs.utexas.edu
Distribution: usa
Reply-To: lihan@ccwf.cc.utexas.edu
While I'm on the net bugging everyone, is there such a thing as a chip
or chipset to decode Code 39 barcode?  I ask for a couple of reasons --
mainly I want a reasonably compact encoding scheme to write information
on magstripe cards and Code 39 appears to be about right.  (If the 'right'
way to do it is something else, and it's reasonably easy, can someone let
me know?)
I might not get a chance to reply too quickly to this or my earlier post,
but I'll get to them within a couple days, I think ..
thanx everyone!  <BGB>  lihan@ccwf.cc.utexas.edu
From: donrm@sr.hp.com (Don Montgomery)
Subject: Radio Shack Battery of the Month Club
Organization: HP Sonoma County (SRSD/MWTD/MID)
X-Newsreader: TIN [version 1.1 PL9.2]
Lines: 10
Radio Shack has canceled their "Battery of the Month" Club.  Does
anyone know why?
They say they'll honor existing cards in customer hands, but no new
cards will be issued.
Don Montgomery
donrm@sr.hp.com
From: johne@vcd.hp.com (John Eaton)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: Hewlett-Packard VCD
X-Newsreader: Tin 1.1 PL5
Lines: 30
-s87271077-s.walker-man-50- (swalker@uts.EDU.AU) wrote:
:
:
: I really don't know where to post this question so I figured that
: this board would be most appropriate.
: I was wondering about those massive concrete cylinders that
: are ever present at nuclear poer sites. They look like cylinders
: that have been pinched in the middle. Does anybody know what the
: actual purpose of those things are?. I hear that they're called
: 'Cooling Towers' but what the heck do they cool?
: I hope someone can help
:-----------------------
During the nuclear fission reaction the uranium fuel can get hot enough
to melt. When this happens the liquid uranium is pumped to the cooling
tower where it is sprayed into the air. Contact with the cool outside air
will condense the mist and it will fall back to the cooling tower floor.
There it is collected by a cleaning crew using shop vacs and is then
reformed into pellets for reactor use the next day.
Cooling towers are a lot taller than they really need to be. Power companies
are forced to make them that tall by some enviromental law that requires the
raw uranium emisions to be held to under 1%. This law is now under attack
by lawyers arguing that the 1% should be measured at the edge of the property
rather than the edge of the cooling tower. Eliminating this law will save
power companies thousands of dollars in concrete costs for new nukes.
John Eaton
!hp-vcd!johne
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Subject: Ungrounded GFCIs; was: Re: A question about 120VAC outlet wiring.
Nntp-Posting-Host: aisun3.ai.uga.edu
Organization: AI Programs, University of Georgia, Athens
Lines: 22
In article <1qmisf$odp@sdl.Warren.MENTORG.COM> garyg@warren.mentorg.com writes:
>>
>>What you CAN do if you want three-prong outlets without additional wiring is
>>to use a GFCI outlet (or breaker, but the outlet will be cheaper).  In fact,
>>depending on where you are putting your new outlet(s), a GFCI may be *required*.
>
>You still need to supply a proper ground for a Ground Fault Circuit Interrupter!
Oddly enough, you don't, at least according to the wiring FAQ that
is regularly posted on misc.consumers.house.
A GFCI senses discrepancies between the live and neutral wire currents,
and cuts them both off if a discrepancy is found.  No ground connection
is needed for it to function.
--
:-  Michael A. Covington, Associate Research Scientist        :    *****
:-  Artificial Intelligence Programs      mcovingt@ai.uga.edu :  *********
:-  The University of Georgia              phone 706 542-0358 :   *  *  *
:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :  ** *** **  <><
Subject: Re: Looking for a good Spice book
From: juhan@piko (Juhan Poldvere)
Organization: Tartu University, Department of Chemistry
Nntp-Posting-Host: piko.chem.ut.ee
X-Newsreader: TIN [version 1.1 PL8]Lines: 17
Lines: 17
In <C5GIA7.7x9@acsu.buffalo.edu> NEIL B. GANDLER
(v064mb9k@ubvmsb.cc.buffalo.edu) wrote:
:>   I am an electrical engineering student and its a must that I get familiar
:> with spice. I have been using it and getting used to it but it would
:> be great to have a good reference manual that explains everything in an
:> organized and concise. I current have "A guide to circuit simulation &
:> Analysis using spice". I feel it has the information is just randomly placed
:> in the book and its not easy to look up small things when you just
:> need a good reference book. I would appreciate any info. Thanks
There is a postscript manual at ic.berkeley.edu in pub/spice3/um.3f.ps
directory (about 650kbytes, 126 pages).
--
Juhan Poeldvere, ES5QX                               | juhan@chem.ut.ee
Tartu University, Dept. of Chemistry                 | fax:   372 (34) 35440
2 Jakobi St., EE-2400, Tartu, Estonia, via Stockholm | voice: 372 (34) 35429
Subject: 2SC1096, 2SA634 specs?
From: juhan@piko (Juhan Poldvere)
Organization: Tartu University, Department of Chemistry
Nntp-Posting-Host: piko.chem.ut.ee
X-Newsreader: TIN [version 1.1 PL8]Lines: 10
Lines: 10
Hi,
Could some kind soul post me the max power/voltage/current ratings of
2SC1096 and 2SA634 transistors, their conductance types and pinouts.
They are used in the sweep portion of a TV set.
Thanks in advance,
--
Juhan Poeldvere, ES5QX                               | juhan@chem.ut.ee
Tartu University, Dept. of Chemistry                 | fax:   372 (34) 35440
2 Jakobi St., EE-2400, Tartu, Estonia, via Stockholm | voice: 372 (34) 35429
From: aras@Ziggy.csl.ncsu.edu (Caglan M. Aras)
Subject: Polaroid Range finder interference-Help!
Organization: /etc/organization
Lines: 26
We have a setup with with 13 polaroid transducers and rangefinders. We
would like to fire these three at a time with about 5 ms between
firings. The three that are being fired do not fire in the same
direction.
To further explain the situation, assume we are firing sonars A,B,C
5 ms apart each other. We should normally see an echo on A that
corresponds to the distance. However, sonar A detects the INIT line
of sonar B! The detection is actually through the transducer of sonar A;
we can see a very faint 50Khz signal on the transducer, exactly at the
time the init line of sonar B is activated.
We feel that there is some ground coupling that is causing this interference.
We came to this conclusion since we are using a separate power supply
for sonars B and C.
Has anyone else had any problems with these particular units and
this type of experience? Your suggestions for remedies will be greatly
appreciated.
--
Caglan M. Aras                 [] aras@eceris.ece.ncsu.edu
ECE Department                 [] ph: 919-515-5405
North Carolina State University[] fx: 919-515-5523
Raleigh, NC 27695              []
From: jra@law7.DaytonOH.NCR.COM (John Ackermann x 2966)
Subject: Single chip receiver for FSK?
Reply-To: jra@law7.DaytonOH.NCR.COM (John Ackermann x 2966)
Organization: NCR Corporation -- Law Department
Lines: 21
My next project is to come up with an IF/detector module for fast -- 112
to 250 kB/sec -- packet radio use.  No fancy modulation scheme, just
wide FSK for use at 902 or 1296 MHz.
I'm a bit familiar with the Motorola 3362 chip, but I wonder if there
are newer designs that might work at higher input frequencies.
My goal is to come up with an inexpensive design for a receiver "back
end" with IF input on one end and an FSK demondulator on the other.  I'm
particularly interested in ways to use a higher IF than 10.7 -- do any
current chips work up to, say 150MHz with internal downconversion so a
normal IF filter can be used?
Any suggestions?
John
--
John R. Ackermann, Jr.         Law Department, NCR Corporation, Dayton, Ohio
(513) 445-2966		       John.Ackermann@daytonoh.ncr.com
Packet Radio: ag9v@n8acv.oh    tcp/ip: ag9v@ag9v.ampr [44.70.12.232]
From: paj@uk.co.gec-mrc (Paul Johnson)
Subject: Re: History question
Reply-To: paj@uk.co.gec-mrc (Paul Johnson)
Organization: GEC-Marconi Research Centre, Great Baddow, UK
Lines: 25
In article <kazel.15.734728882@uiuc.edu> kazel@uiuc.edu (Mitch Kazel) writes:
>Sorry if this isn't the correct news group . . . but . . .
>
>A colleague of mine is trying to find out when the first public use of
>electronic voice amplification was  . . . i.e. a P-A system.
>
>Any reference would be appreciated.  Please reply via e-mail.
>Mitch Kazel (N9HDQ)
>INTERNET:  kazel@uiuc.edu
This is vague, so I am posting it in case anyone else knows more.
I recall reading of a phonograph which used mechanical amplification.
Compressed air was squirted out of a valve which was controlled by the
pickup.  The result was noisy and distinctly lo-fi, but much louder
than a conventional phonograph.  It tended to wear the disks out
pretty quickly though.
Paul.
--
Paul Johnson (paj@gec-mrc.co.uk).	    | Tel: +44 245 73331 ext 3245
--------------------------------------------+----------------------------------
These ideas and others like them can be had | GEC-Marconi Research is not
for $0.02 each from any reputable idealist. | responsible for my opinions
From: horne@cs.utexas.edu (Patrick J. Horne)
Subject: Thermal fuse supplier wanted
Organization: CS Dept, University of Texas at Austin
Lines: 21
NNTP-Posting-Host: im4u.cs.utexas.edu
Keywords: MITI
I have a thermal fuse from a Apple Laserwriter II power supply (Made
by Cannon) that I need to replace.  The fuse is not the standard
tubular thermal fuse like those found in hair driers etc, but is a
rectangular plastic package, much like a transistor or diode.  It
is about 0.2"x0.2"x0.1", with both leads coming out of one of the
0.1"x0.1" sides.  I have been told that it was made by MITI, a asian
company, but I can find no information as to a supplier.  This fuse
is rated at 1A, 130C.  Does anyone have a source for this fuse?  I
only need 5 or so, which means that the manufacturer wouldn't even want
to talk to me, let alone, deal with me.
Please advise via E-mail.
Thanks,
Pat
--
---  I like boats and bicycles, they're healthier than Valium  ---
Pat Horne, Network Manager, Shop Supervisor, Hardware Guru
CS Dept, University of Texas, Austin, Tx. 78712 USA
voice (512)471-9517, fax (512)471-8885, UUCP:cs.utexas.edu!horne
From: pat@fegmania.wustl.edu (Pat Niemeyer)
Subject: Re: $25 network
Organization: Washington University in Saint Louis, MO USA
Lines: 14
Reply-To: pat@fegmania.wustl.edu
NNTP-Posting-Host: fegmania.wustl.edu
Originator: pat@fegmania
>>The same folks now have out LBL (Little Big Lan) for $75.  I think you
>>get it for $50 if you already own $25 Network.  LBL works with Arcnet,
>>parallel ports, and serial ports in any combination for up to 250 or so
>>nodes.
No flames please, but I picked up this discussion a bit late and I
am really curious...
What exactly *is* the $25 network?
Something to hack together N serial cables?
Something with N serial drivers?
Thanks,
Pat
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: TDR plug-in
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 15
If anyone out there has an HP180 series scope or mainframe, I
have the TDR plug in (the 1810, I believe) for it and have no need
to keep it. Interested? E-mail me.
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: Emulator pods
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 23
A surplus-dealing buddy of mine came up with two emulator pods:
HP64220C (for HP 64100 development station). 8086 target
processor. DIP head. Does not include board that plugs into
the 64100.
Applied Microsystems 80C186/188 pod, LCC head.
If you have an interest in either, let me know. They look to
be in excellent condition. He doesn't know what to do with them, which
may mean that they'll be cheap.
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: bill@xpresso.UUCP (Bill Vance)
Subject: Re: help - how to construct home-built battery for 3rd grade sci report
Distribution: usa
Organization: (N.) To be organized.  But that's not important right now.....
Lines: 32
X-Newsreader: TIN [version 1.1 PL9]
Dean Anneser (anneser@pwa-b.uucp) wrote:
: My 9 yr old son has signed up to do a science report on batteries.  I was
: wondering if anyone could provide me with some information as to how to
: construct a home-built battery.  In my grade school days, I remember seeing
: the 'ice cube tray' version, but I don't remember what to use as a good
: electrolyte or what the easily obtainable metals were.
: Thank you in advance.
: Dean W. Anneser                  Pratt & Whitney Aircraft
: Computer System Specialist       m.s. 161-05                       \__ -\
: (203)565-9372 (desk) 5016 (fax)  400 Main St.               Ooo.. (_)-V/( )
: Uucp:     uunet!pwa-b!anneser    East Hartford, CT  06108    Live to Ride
: Internet: anneser@pwfire.pweh.utc.com
: "One test result is worth one thousand expert opinions" -- Wernher Von Braun
: --
: Dean W. Anneser                  Pratt & Whitney Aircraft
: Computer System Specialist       m.s. 161-05                       \__ -\
: (203)565-9372 (desk) 5016 (fax)  400 Main St.               Ooo.. (_)-V/( )
: Uucp:     uunet!pwa-b!anneser    East Hartford, CT  06108    Live to Ride
--
The simplest one is easy.  Take a lemon or other citrus type fruit, and
stick a pair of metal strips into it for the contacts.  The two strips must
be of disimelar metals like copper and zinc.  Then connect a voltmeter to
the contacts and read the voltage.
bill@xpresso.UUCP                   (Bill Vance),             Bothell, WA
rwing!xpresso!bill
You listen when I xpresso, I listen When uuxpresso.......:-)
From: miller@hmsp04.wg3.waii.com (Griff Miller X7114)
Subject: Re: 68000
Organization: Western Geo. - Div of Western Atlas Intn'l Inc., Houston, TX
Lines: 24
Nntp-Posting-Host: hmsp04.wg3.waii.com
In article <1993Apr15.060043.15664@serval.net.wsu.edu> rwilley@eecs.wsu.edu (Ronald Willey - CS) writes:
>
>	The Supra accelerator that is mentioned in one of the pervious
>articles, is not 68000 or 68020 based.  It runs on a 68030 at 28Mhz and
>the design they are using is very simple( if you were referring to the
>A500 exteranal model).
Hmm - I don't think you and I are thinking of the same thing. I was the
original poster, BTW. The accelerator that I'm talking about almost
certainly uses a 68HC000, according to the footnotes in the Supra ad. It
only costs $199 list, so I really doubt if it has a 28 MHz 68030 inside.
It's called the Supra 28, or Supra Turbo 28.
There's an external A500 model, and an internal A2000 model.
BTW, does anyone know if a 28Mhz 68HC010 exists?
--
Griff Miller >  Griff.Miller@waii.com  < use this for email.
*** My opinions are mine, not Western's. ***
"Dear friend, do not imitate what is evil but what is good.
Anyone who does what is good is from God. Anyone who does
evil has not seen God." - 3 John 9
From: bps@ektools.kodak.com (Bruce P. Sidari)
Subject: Re: A question about 120VAC outlet wiring..
Organization: Eastman Kodak
Lines: 29
In article <1993Apr15.212629.1834@cmkrnl.com> jeh@cmkrnl.com writes:
>In article <1993Apr14.172145.27458@ecsvax.uncecs.edu>, crisp@ecsvax.uncecs.edu (Russ Crisp) writes:
>> I'm considering modernizing some old wiring in my home, and
>> I need a little advice on outlet wiring.  Several outlets
>> are the old 'two prong' type, without the ground.  Naturally,
>> the wire feeding these outlets is 12/2, WITHOUT the ground
>> wire.  I noticed at the fusebox that some circuits have the
>> 12/2 with ground, and that on these circuits, the ground
>> wire was tied to the same bus as the neutral (white) wire.
>
>They are supposed to be connected together at the breaker panel... but nowhere,
>repeat NOwhere, else.  (Well, almost.  There are strange exceptions for things
>like sub-panels.)
>
>
>	--- Jamie Hanrahan, Kernel Mode Systems, San Diego CA
>Internet:  jeh@cmkrnl.com  Uucp: uunet!cmkrnl!jeh  CIS: 74140,2055
>
Not even in sub panels!  The only place the neutral should be connected to the
ground is in a SERVICE DISCONNECT!  In your house the "main" panel serves as
the service disconnect.  Sub panles in your garage or workshop for example must
maintain seperate neutral and ground busses because they are not  service
disconnect equipment.
Steve Woodard, KD2KQ - not a licensed electrician, but I can read the NEC book.
(my brother is though)  :)
Subject: Re: Exploding TV!
From: xhan@uceng.uc.edu (Xiaoping Han)
Distribution: usa
Organization: University of Cincinnati
Lines: 12
In article <1qk4hj$qos@vtserf.cc.vt.edu> prasad@vtaix.cc.vt.edu (Prasad Ramakrishna) writes:
>... Why would the picture tube explode or even smoke?
It's not the picture tube. More likely the flyback. Emerson? can't admire.
Han
>Prasad
>prasadr@vtvm1.cc.vt.edu
>
From: hooperw@spot.Colorado.EDU (Wayne Hooper)
Subject: Re: making copy of a Video tape
Keywords: video
Nntp-Posting-Host: spot.colorado.edu
Organization: University of Colorado, Boulder
Lines: 13
victor@inqmind.bison.mb.ca (Victor Laking) writes:
>You are experiencing what is called Macrovision.  It is the protection
>that they use on the video tapes.  There are two ways around this that I
>know of.  First of all, you can try using a different VCR to copy onto.
>It is the input of the VCR that reacts to the protection so sometimes
>just switching the two VCRs around will take care of it.  Some models
>just don't react to it.
Does this also affect the viewing of tapes ? I have had problems with
a couple of rented tapes; they were virtually unviewable. I fiddled
with the tuning, tracking and vertical hold but it was no good.
From: lperez@decserv2.eecs.wsu.edu (Luis G. Perez)
Subject: Re: BEAM Robot Olympic Games next Week in Toronto.
Organization: S
Lines: 10
Does anybody know if there is a mailing list or newsgroup for
Power Systems and related areas?
Thanks,
--
Luis G. Perez
lperez@eecs.wsu.edu
From: cgordon@vpnet.chi.il.us (gordon hlavenka)
Subject: Re: what to do with old 256k SIMMs?
Organization: Vpnet Public Access
Lines: 14
jhaines@eniac.seas.upenn.edu (Jason Haines) writes:
>	I was wondering if people had any good uses for old
>256k SIMMs...  So, if you have an inovative use (or want to buy
>some SIMMs  8-) ), I would be very interested in hearing
>about it.
About a month ago there was a photo posted on
alt.binaries.pictures.misc of a 17.5-inch Northern Pike which had been
caught on a lure made of 256K SIMMs.
--
----------------------------------------------------
Gordon S. Hlavenka           cgordon@vpnet.chi.il.us
Vote straight ticket Procrastination party Dec. 3rd!
From: heuvel@neptune.iex.com (Ted Van Den Heuvel)
Subject: Motorola MC14315 and MC143120
Originator: heuvel@neptune.iex.com
Organization: iex
Lines: 12
Let me try sending this message again, I botched up the margins the
first time; *sorry* 'bout that :)
Does anyone out there know of any products using Motorola's Neuron(r)
chips MC143150 or MC143120. If so, what are they and are they utilizing
Standard Network Variable Types (SNVT)?
________________________________________________________________________
Ted Van Den Heuvel   heuvel@neptune.iex.com
KX5P
________________________________________________________________________
From: tomb@hplsla.hp.com (Tom Bruhns)
Subject: Re: Trace size for a 15 Amp supply
Organization: HP Lake Stevens, WA
Lines: 34
acollins@uclink.berkeley.edu (Andy Collins) writes:
>How thick do I need to make a PCB trace for 15 Amps of current? and
>Does anybody have any other thoughts on the process (what kind of PCB
>to use, materials, thickness of copper, any advice graciously accepted)?
In four replies, I've seen no hard numbers, so here goes:  For traces
on the outside (not inner layers), expect, in 1 oz copper, at 15 amps,
the following temperature rises versus width.  This is from Sams'
"Reference Data for Engineers," seventh edition, Pg 5-30, which claims
in turn to be from MIL-STD-275C...
width   Temp rise
inches  degrees C
------  ---------
.125	100
.15	 75
.17	 60
.20	 45
.24	 30
.33	 20
At 10 amps, the rise for the .125 width is only about 30 degrees.
Power goes as square of the current, plus the copper resistance goes
up as temperature goes up...  Certainly .20" (~5mm) traces should be
ample for what you want to do.  And 2 ounce copper almost cuts the
required width in half.  (I'd do 2 oz at about 0.08" width myself,
I think...given that the _rated_ current is 10 amps and the 15 is
a transient or fault condition.)
(There's another question: will the voltage drop be low enough?
But you should be able to figure this one out with wire tables or
just the resistivity of copper.  Keep traces short and use separate
sensing traces where appropriate, as mentioned by another poster.)
From: tomb@hplsla.hp.com (Tom Bruhns)
Subject: Re: Looking for 900MHz Spread Spectrum Modules
Organization: HP Lake Stevens, WA
Lines: 12
butts@shocker.ee.twsu.edu (Ronald W. Butts, Jr.) writes:
>I am looking for suppliers of 900MHz spread spectrum radio modules. I need
>to implement a two-way audio band link (essentially the guts of a cordless
>900MHz phone is what I want.)
This isn't exactly audio, but take a look in "RF Design" magazine,
April 93, for the article "A Robust Signaling Technique for Part 15
RF Control Netowrk Applications."  Page 29.  Sources of parts are
mentioned; in the same issue is an article that features a chipset
for the Digital European Cordless Telecommunications standard.
From: tomb@hplsla.hp.com (Tom Bruhns)
Subject: Re: A question about 120VAC outlet wiring..
Organization: HP Lake Stevens, WA
Lines: 21
crisp@ecsvax.uncecs.edu (Russ Crisp) writes:
>SO..  Here's my question.  It seems to me that I'd have the
>same electrical circuit if I hooked a jumper from the neutral
>over to the ground screw on new 'three prong' grounding outlets.
>What's wrong with my reasoning here?
May I respectfully suggest you NOT do this??  The ground is
supposed to be a protective ground, and though what you suggest
looks good on paper, it's dangerous to rely on the same wire for
power and protection.  It'd never meet code, and if you now own
the property and later sell it, you may end up with liabilities
you don't want, and if you _don't_ now own it, well...
There's a "wiring" FAQ that I think addresses this.  I believe
an alternative is use of a GFCI, but I'm really not sure what
current code allows in this area.  The GFCI senses alternate
(unwanted) current paths, and doesn't rely on a specific
protective ground wire, at least not beyond the GFCI in the
protected circuit.  GFCI breakers are available (but expensive).
From: glenne@sr.hp.com (Glenn Elmore)
Subject: Re: Single chip receiver for FSK?
Organization: HP Sonoma County (SRSD/MWTD/MID)
X-Newsreader: TIN [version 1.1 PL9.2]
Lines: 78
John Ackermann x 2966 (jra@law7.DaytonOH.NCR.COM) wrote:
: My next project is to come up with an IF/detector module for fast -- 112
: to 250 kB/sec -- packet radio use.  No fancy modulation scheme, just
: wide FSK for use at 902 or 1296 MHz.
: I'm a bit familiar with the Motorola 3362 chip, but I wonder if there
: are newer designs that might work at higher input frequencies.
: My goal is to come up with an inexpensive design for a receiver "back
: end" with IF input on one end and an FSK demondulator on the other.  I'm
: particularly interested in ways to use a higher IF than 10.7 -- do any
: current chips work up to, say 150MHz with internal downconversion so a
: normal IF filter can be used?
: Any suggestions?
: John
What you describe is very close to what I built and described in the
10th ARRL Computer Network Conference proceedings.
I built 10 watt FSK transceivers at 904 MHz.  They are essentially
double conversion transverters with digital mod and demod at 29 MHz.
The receiver uses the MC13055 which is the same FSK receiver chip I used
previouslyu in the 2 Mbps 10 GHz data link I first published in Ham
Radio and which is now also in the ARRL handbook.
The MC3356, which includes a VHF converter section, could also be used
at these speeds.  There is a newer and perhaps slightly improved design
of this (the MC13056 if I remember rightly).
While using this would have let me reduce the "external" IF count on
receive, it didn't really offer all that much help on transmit so I
didn't bother with it.
The radios I built were first designed and built for 512 kbps in a 2
MHz channel but later reduced to half that.  These 256 kbps radios
actually have done quite well in across-the-bench tests at 384 kbps and
speed is pretty much a function of filter design.  Handling the data
stream is another matter entirely.
Some of the existing radios are currently deployed on hilltops in a
"beacon" test mode.  While there is not yet end-end two-way data flow
due to lack of resources to debug software for the digital hardware (MIO
also shown in the CNC proceedings), data is perfect copy at n6gn.  Even
though the data clock is currently at about half speed, the a 2+ kbytes
of the test text (chapter 55 of Isaiah) takes only a little over 1/8 of
a second.
I've been hoping that someone would get interested enough to step in
and get involved in writing code to make the whole thing usable (Borland
IDE environment with remote debugging possible as mentioned in the
proceedings) but to date a couple of us have been on our own and running
low on resources of time, money and energy.
If anyone in the SF bay area wants to check it out there is also a CW
ID after the text on the mark side at 904.740 MHz from beacons on Sonoma
Mtn and Black Mtn (overlooking Si valley).  The antenna is horizontally
polarized.
I guess in retrospect my suggestions are that this is a fairly costly
approach if the radios are intended for users rather than backbones and
you might want to carefully consider your "target".  If you can't
arrange your paths such that you have complete line-of-sight I think
you'll want to address the inter-symbol-interference caused by
multipath and probably link C/N budgets if paths are very far from LOS.
For more details, see the 10th CNC.  I'm currently working on a spread
spectrum, direct conversion design to address some of these problems.
I'd be glad to help as I can with any design problems.
73
Glenn Elmore n6gn
N6GN @ K3MC
amateur IP:	glenn@SantaRosa.ampr.org
Internet:	glenne@sr.hp.com
From: dtmedin@catbyte.b30.ingr.com (Dave Medin)
Subject: TDR plug-in
Reply-To: dtmedin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Lines: 18
I have an HP 1815 TDR plug-in for an HP180 series scope or mainframe
that I'm never going to use (no scope any more). If you're interested
in it, please let me know. Price? Probably real cheap.
This notice may have appeared once before. I posted, and it never showed
up on our local server...
--
--------------------------------------------------------------------
Dave Medin			Phone:	(205) 730-3169 (w)
SSD--Networking				(205) 837-1174 (h)
Intergraph Corp.
M/S GD3004 		Internet: dtmedin@catbyte.b30.ingr.com
Huntsville, AL 35894		UUCP:  ...uunet!ingr!b30!catbyte!dtmedin
******* Everywhere You Look (at least around my office) *******
* The opinions expressed here are mine (or those of my machine)
From: shanlps@ducvax.auburn.edu
Subject: TV RECEPTION:  HEELLLPPP!!!
Lines: 18
Nntp-Posting-Host: ducvax
Organization: Auburn University, AL
Lines: 18
Hello,
I just canceled my support of the Cable Regime and I would like to at
least pick up the 3 networks and NBC.  :)   I do not have tons of
money nor even a few pounds so what I am looking for is the best solution
for reception for under 100 dollars.  I have seen modules that you plug
into your wall outlet that "supposedly" make your entire house an
antenna.  I have to admit, even with my limited knowledge of wavelength
and aerial reception, this seems dubious in its claims for "excellent
reception" at best.  I'll try anything, though, if it WORKS.  I am in
a non-mountainous area, approximately 50 miles from the transmitting stations
which are pretty large (Montgomery Alabama pop. 200,000) and Colombus Goergia,
pop. 100,000+.  Any recommendations of products, brand-names, prices and
company info (catalog ordering numbers, addresses etc.)?  Thank you in
advance.
Paul Sylvester Shanley   pshanley@humsci.auburn.edu   VOICE 205 887 7440
From: ddr@flux.isr.alaska.edu (Donald D Rice)
Subject: Heavy-duty antenna simulation software
Nntp-Posting-Host: flux.isr.alaska.edu
Organization: Geophysical Institute, Fairbanks, AK
Lines: 21
I would be interested in hearing from anyone who knows of good software for
antenna simulation, particularly in source form suitable for Unix workstations
(though good PC software would also be of interest).
I'm aware of the numerous mininec mutations, and have been using MN for
some time now.  I'm primarily interested in HF, VHF, and low UHF (< 500 MHz)
designs, mostly wire antennas, but for thick wires and mesh surfaces as well
as for your basic thin wire assumption.
Is anything interesting happening with NEC itself?  I've seen a version
that was mutilated to run (sort of) under Microsoft Fortran, but I'm not
sure how many "new and improved" versions of the code might be out there
somewhere.
I'd also be interested in non-NEC derivatives.  The ones I've seen have
been aimed at microwave applications, but if there is something out there
useful at the lower frequencies, I'd like to know about it.
Thanks,
--
Don Rice                   E-mail: ddr@flux.isr.alaska.edu    (Internet)
Geophysical Institute              fnddr@alaska               (BITNET)
University of Alaska               flux::ddr                  (SPAN)
Fairbanks, AK 99775        Phone:  (907) 474-7569        Loran: 64.86N 212.16E
From: alung@megatest.com (Aaron Lung)
Subject: Re: IC Packages
Organization: Megatest Corporation
Lines: 58
In article <1993Apr16.142715.12613@sol.ctr.columbia.edu> seema@madvlsi.columbia.edu (Seema Varma) writes:
>Hi,
>	I am looking for some help in choosing a package
>for a high-speed silicon ADC (100Mhz) currently being
>fabricated. This is a PhD research project and I have to test
>the chip at speed on a PCB. I expect to have roughly 100
>packaged circuits and will do DC, low-speed and high-speed
>testing using 3 different set-ups for the test chip.
>
>	I know for sure that a DIP will not work
>(the long lead lines have too high an inductance).
>Getting a custom-made package is too expensive, so
>I am trying to choose between a flatpak and a
>leadless chip carrier. The flatpack would be hard
>to test since it has to be soldered on to the test
>setup and I would spend loads of time soldering
>as I kept changing the test chip. The leadless chip
>carrier sockets also have long lead lines and may
>not work at high speeds.
>
>	Does anyone out there have experience/knowledge
>of this field ? I would greatly appreciate help! Any ideas/
>names of companies manufacturing holders/sockets/packages
>would help.
>
>P.S. The multi-layer fancy GaAs packages seem like a bit
>of overkill(?)
>
> --- Seema Varma
You didn't mention whether or not cost is an issue.  Where
exactly are you running 100MHz??  THe digital side?  TTL?
ECL?  We run 200MHz and 100MHz all over our IC test equipment
all day long in the ECL domain, and we use DIP's along
with PLCC's, 25mil and 20mil pitch 256pin QFP's to name
a few.  I don't see a problem in packaging as long
as you adhere to sound engineering practices.
A good source of information is Motorola's MECL System Design
Handbook. The latest ed. is dated 2/88.  That is considered
to be one of the *bibles* in high-speed design.
The very fact that you need to build a test fixture means
you're most likely going to need a socket.  It in itself
has far more inductance per pin than the package you are
testing, not to mention any impedance discontinuities.  I
don't see the big concern over the packaging because it
probably isn't going to make that much difference
If you're trying to get TTL to run at 100MHz, have fun...
TTL was never designed to run in a 100MHz environment.
:-(
aaron
P.S. My opinions have nothing to do with my company...the
standard disclaimer applies.
From: alung@megatest.com (Aaron Lung)
Subject: Re: Adcom cheap products?
Organization: Megatest Corporation
Lines: 30
In article <1993Apr16.105738.20864@hippo.ru.ac.za> webb@itu1 (90-29265  Webber  AH) writes:
> ...stuff deleted...
>
>I was also sceptical about the amps being built in the far-east
>  or where-ever.  But if you look in the amp and see what components
>  they use and how it was designed, you can easily see why the
>  amplifiers sound so brilliant.
Good point...also, I wouldn't be surprised that the components
they use off-shore are of inferior quality.  As long as it was
properly designed and robust, premium components are used, it
shouldn't matter where it is assembled.
>I cannot see why people say the amplifier won't last - not with
>  those quality components inside.  Sure the amp runs very fairly
>  hot - but that's how you get an amp to sound incredibly good.
An amp that runs hot has no bearing on how it's gonna sound.
The amp you have probably is running Class-A the whole day.
Actually, I'd be wary of excessively hot amps, 'cauz even though
the components inside may be rated to run that way, excessive
heat will dramatically shorten the life of *any* electronic component
regardless of quality.  In fact, an amp that does run hot to the touch is
because either the engineer or manufacturer of that amp wanted
to skimp on heatsinking or cooling to save costs!  Hmmmmm....
aaron
.
From: whit@carson.u.washington.edu (John Whitmore)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Article-I.D.: shelley.1qngqlINNnp8
Organization: University of Washington, Seattle
Lines: 25
NNTP-Posting-Host: carson.u.washington.edu
In article <C5L5x0.KJ7@vcd.hp.com> johne@vcd.hp.com (John Eaton) writes:
>-s87271077-s.walker-man-50- (swalker@uts.EDU.AU) wrote:
>During the nuclear fission reaction the uranium fuel can get hot enough
>to melt. When this happens the liquid uranium is pumped to the cooling
>tower where it is sprayed into the air.
Nonsense.  First, the uranium fuel is sealed in zirconium
alloy cylinders (which don't melt in any circumstances short of
major failure of the power plant).  Second, the primary water
(that circulates inside the reactor core) is never pumped into the
cooling tower (it's the SECONDARY water cycle that goes
through the cooling tower).  Third, liquid uranium would burst
into flame on contact with air.
>Contact with the cool outside air
>will condense the mist and it will fall back to the cooling tower floor.
>There it is collected by a cleaning crew using shop vacs and is then
>reformed into pellets for reactor use the next day.
Cleaning crew working in a mist of uranium?  This is a
toxic heavy metal, even if it WEREN'T radioactive.  Shouldn't there
be some smileys here?  Or frowneys?
John Whitmore
From: rsf@cbnewsb.cb.att.com (roberto.s.freire)
Subject: Fluke Scopemeter
Organization: AT&T
Lines: 14
Has anybody out there used/tested these new Fluke Scopemeters?
How do they compare to a low-end Tectronix oscilloscope? Are
there any big drawbacks about these handheld scopes when
compared to the benchtop scopes of the same price range
($1000-$2000)?
Any info on the Fluke Scopemeters would be greatly appreciated.
Thanks,
Bob Freire
rsf@houxa.att.com
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Subject: Re: TV RECEPTION:  HEELLLPPP!!!
Nntp-Posting-Host: aisun3.ai.uga.edu
Organization: AI Programs, University of Georgia, Athens
Lines: 14
At 50 miles, a conventional set of TV antennas on a pole (one aimed
at each transmitter location) should work well.
"Rabbit ears" inside the house are probably not adequate.
Gadgets to plug into your house wiring are even worse.
At VHF, you don't want a _big_ antenna, you want a _resonant_
antenna.
--
:-  Michael A. Covington, Associate Research Scientist        :    *****
:-  Artificial Intelligence Programs      mcovingt@ai.uga.edu :  *********
:-  The University of Georgia              phone 706 542-0358 :   *  *  *
:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :  ** *** **  <><
From: pmalenfa@kitkat.webo.dg.com (Paul Malenfant)
Subject: Optoisolator interfacing questions
Reply-To: pmalenfa@kitkat.webo.dg.com (Paul Malenfant)
Organization: Data General Corporation, Westboro, MA
Lines: 26
I am interfacing some simple circuits that run on 9V to my
cpu board which runs at 5-6V.  The optoisolator is a 4N35.
On the led side, I put the signal I want through a 10k resistor
to the base of a 2N2222.  On the transistor side, I tie my
cpu input line to the collector which has a pull-up resistor
of 47k.
It functions OK, but seems VERY slow.  I can detect pulses
that occur at about 2kHz, but not much faster.  Isn't the
rise/fall time of this device, something like 5uS?  I should
be able to detect my target of 40kHz, but I can't get 16kHz.
This is done using wire-wrap and the wires going to the cpu
and to the test pin are about 8 inches long, but I'm not
doing anything high-speed.
In the Art of Electronics, it mentions tying the base of the
phototransistor to ground through a resistor to improve the
speed.  Is that what I need to do?  How do I calculate the
resistor value?
--
Paul Malenfant
pmalenfa @ kitkat.webo.dg.com (508-870-6460)
From: segal@rtsg.mot.com (Gary Segal)
Subject: Pinout needed for TIL311
Nntp-Posting-Host: corolla7
Organization: Motorola Inc., Cellular Infrastructure Group
Lines: 17
I've recently picked up some TIL311 display chips, but I can't find
any information on them.  It seems they are no longer made by TI, and
I don't have an old enough data book.  :-(
It appears to have a dot-matrix led display capable of showing one hex
digit.  It is in a 14 pin DIP package, but pins 6, 9, and 11 are not
present.
If you have any information on this part (pinout, power requirments,
functions, ...) please send me e-mail.
Thank You,
--
Gary Segal                             Motorola Inc.
segal@oscar.rtsg.mot.com               Cellular Infrastructure Division
--- we are standing here only to gaze at the wind ---
From: martinkm@leland.Stanford.EDU (Kenneth michael Martin)
Subject: PADS model of a 68hc11.
Organization: DSG, Stanford University, CA 94305, USA
Lines: 5
Has anyone done a model of the 52 pin version of the 68hc11?  It doesn't
seem to be too big a job, but if someone else has already done it ...
many thanks
Ken Martin
From: jeh@cmkrnl.com
Subject: Re: Need help with car stereo....
Organization: Kernel Mode Systems, San Diego, CA
Lines: 38
In article <1qih53$9ho@usenet.INS.CWRU.Edu>, ae454@cleveland.Freenet.Edu
(Paul Simundza) writes:
> My friend has a nice Alpine car stereo, and it only has 2 channels,
> but one of them does not work. It does not put out any current or voltage
> at all, is that channel therefore blown?  I then shut the radio off and
> ran continuity into the two speaker ouputs of the channel, and it charged
> and discharged so I know the wires just aint bad....
This probably only tells you that the DC blocking capacitor that's in series
between the one-chip, single-ended audio amp and the speaker terminal is there.
> any Ideas?
Open it up and look for the power amp "ICs".  They'll be fairly obvious.
Replace the one connected to the dead output.
> also,
> how would I locate where the signal of the radio/tape unit is BEFORE it
> gets amplified, because then couldn't I hook up RCA outputs to that signal
> so then he could just use a little amplifier?
Well, one thing you should do is poke around the terminals of the power amp
chips.  Use a probe with a 10M resistor (like a scope probe) connected to the
input of a small audio amp w/speaker.  If you find line-level input to both
chips, one of the chips is bad and can probably replaced pretty easily.
If you want to pick off a near-line-level signal, suitable for feeding to an
outboard amp, the outer legs of the volume control pot will often be good
enough.  This is *before* the volume control (and usually before the tone and
balance controls too).  If you take off from the center and ground legs of
the volume pot, this will be after the volume control (but again, probably
before the other controls).
If the unit is a modern type with an electronic volume control chip, you should
probably forget the whole thing.
--- Jamie Hanrahan, Kernel Mode Systems, San Diego CA
Internet:  jeh@cmkrnl.com  Uucp: uunet!cmkrnl!jeh  CIS: 74140,2055
From: Mike Diack <mike-d@staff.tc.umn.edu>
Subject: Anyone know about DATA I/O device proggers ?
X-Xxmessage-Id: <A7F5DAE6E6026550@dialup-slip-1-80.gw.umn.edu>
X-Xxdate: Sat, 17 Apr 93 16:03:50 GMT
Nntp-Posting-Host: dialup-slip-1-80.gw.umn.edu
Organization: persian cat & carpet co.
X-Useragent: Nuntius v1.1.1d7
Lines: 9
I keep finding these programmers in local junk shops. This may
mean that they are indeed junk - but i'd like to hear from anyone
else that may have met up with them. The basic device is a
"Data I/O 29A universal programmer", and the usual pod is a
"LogicPak 303A-Vo4" with a "303A-001" programming tester/
adapter. I'd really like to hear from anyone who knows whether
these monsters are worth bothering with. All i want to do is blast
PALCE22V10s. - Ideas, folks
Mike.
From: wb8foz@skybridge.SCL.CWRU.Edu (David Lesher)
Subject: Re: History question
Organization: NRK Clinic for habitual NetNews abusers - Beltway Annex
Lines: 24
Reply-To: wb8foz@skybridge.scl.cwru.edu (David Lesher)
NNTP-Posting-Host: skybridge.scl.cwru.edu
Others said:
{early PA?}
# I recall reading of a phonograph which used mechanical amplification.
# Compressed air was squirted out of a valve which was controlled by the
# pickup.  The result was noisy and distinctly lo-fi, but much louder
# than a conventional phonograph.  It tended to wear the disks out
# pretty quickly though.
An now-deceased prof told us willing students about a project he had
worked on during WWII.
They needed a mega-power PA with very clear audio quality. The purpose
was to bellow at refugees from aircraft.
Their solution was a giant compressed-air source, and a horn with
parallel shutters worked by a small audio system. I think he said it
worked very well, thus the War Dept. cancelled the project ;_}.
--
A host is a host from coast to coast..wb8foz@skybridge.scl.cwru.edu
& no one will talk to a host that's close............(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
From: ankleand@mtl.mit.edu (Andrew Karanicolas)
Subject: Re: IC Packages
Organization: MIT Microsystems Technology Laboratories
Lines: 31
NNTP-Posting-Host: ampere.mit.edu
In article <1993Apr16.142715.12613@sol.ctr.columbia.edu> seema@madvlsi.columbia.edu (Seema Varma) writes:
>Getting a custom-made package is too expensive, so
>I am trying to choose between a flatpak and a
>leadless chip carrier. The flatpack would be hard
>to test since it has to be soldered on to the test
>setup and I would spend loads of time soldering
>as I kept changing the test chip. The leadless chip
>carrier sockets also have long lead lines and may
>not work at high speeds.
>
>	Does anyone out there have experience/knowledge
>of this field ? I would greatly appreciate help! Any ideas/
>names of companies manufacturing holders/sockets/packages
>would help.
Check with Kyocera America, Inc.
24 Prime Park Way, Suite 150
Natick, MA 01760
They are one of the largest manufacturers of IC packaging in the
world.
It sounds like you would be a good candidate for wafer probing or at
least IC probing to test performance.  HP, Cascade Microtech and
Tektronix should be able to help you here.  One note, testing at high
frequency accurately can be an *expensive* business.
--
Andrew Karanicolas
MIT Microsystems Technology Laboratory
ankleand@mtl.mit.edu
From: wb8foz@skybridge.SCL.CWRU.Edu (David Lesher)
Subject: Re: Exploding TV!
Organization: NRK Clinic for habitual NetNews abusers - Beltway Annex
Lines: 11
Distribution: usa
Reply-To: wb8foz@skybridge.scl.cwru.edu (David Lesher)
NNTP-Posting-Host: skybridge.scl.cwru.edu
Others said:
# >... Why would the picture tube explode or even smoke?
Naw, it was the penguin on TOP of the set that exploded...
;-}
--
A host is a host from coast to coast..wb8foz@skybridge.scl.cwru.edu
& no one will talk to a host that's close............(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
From: lzahas@acs2.bu.edu (Lukas Zahas)
Subject: Re: How do DI boxes work?
Organization: Boston University, Boston, MA, USA
Lines: 19
In article <LANCER.93Apr15150228@oconnor.WPI.EDU> lancer@oconnor.WPI.EDU (Stephe Lewis Foskett) writes:
>
>I'm doing sound for a couple of bands around here and we need Direct
>Input boxes for the keyboards.  These are the little boxes that take a
>line level out of the keyboard and transform it into low-Z for the run
>to the mixer.  Sadly they cost like $50 (or more) each and I'm going
>to need like 5 or 10 of them!  I looked inside one (belonging to
>another band) and it looks like just a transformer.  Does anyone have
>any plans for building them?
>
$50 each!!  Don't bother trying to make one yourself, just shop around a
little.  I've found DOD brand DI boxes for as cheap as $20 each.  You can
get higher end ones for more, but for PA use for bands, I wouldn't bother.
Making one yourself might work, but getting a sturdy enough enclosure might
be hard (they're made of heavy guage metal, since they're always on the floor,
being kicked around a lot). For any additional questions on this topic, you
might want to post to rec.audio.pro
Lukas Zahas
lzahas@bu.edu
From: kolstad@cae.wisc.edu (Joel Kolstad)
Subject: Radio Shack voice recognition chips
Organization: U of Wisconsin-Madison College of Engineering
Distribution: usa
Lines: 10
Hi there,
I have a friend who'd like to get a hold of a bunch of those simple voice
recognition chips that Radio Shack used to sell (and no longer does).  If
anybody knows of a source for these, please e-mail me.  I'll forward the
responses to him.
Thanks!
---Joel Kolstad
From: Mark-Tarbell@suite.com
Subject: Switch-mode power supply
Organization: Suite Software
Lines: 17
Reply-To: suite!tarbell@uunet.uu.net
NNTP-Posting-Host: gilgamesh.suite.com
Is there a typical component or set of components
that are at fault when a switch mode power supply
goes south?
The supply is for a disk drive. Any general hints
would be appreciated!
Thanks!
Mark-Tarbell@suite.com
at fault when a switch mode power supply
goes south?
The supply is for a disk drive. Any general hints
would be appreciated!
Thanks!
Mark-Tarbell@s$$BVh(J
From: rgc3679@bcstec.ca.boeing.com (Robert G. Carpenter)
Subject: Re: Can Microwaves Be Used To Collect XYZ Coordinates
Organization: Boeing
Lines: 6
Where can you get info (brochures...) on Differential GPS Systems and where to
buy them?
BobC
From: psgwe01@sdc.boeing.com (Gerald Edgar)
Subject: Re: help - how to construct home-built battery for 3rd grade sci report
Keywords: 3rd grade science report
Distribution: usa
Organization: Boeing Computer Services (ESP), Seattle, WA
Lines: 15
Nntp-Posting-Host: crystal
In making batteries you could use copper and zinc in an acid electrolyte.
Copper=copper wire (pennies are now mostly zinc if I recall correctly)
zinc= zinc strip (Hardware stores arround here (Seattle) sell this to prevent
moss buildup on the roof. An alternative would be to use a galvanized
(zinc coated) nail
electrolyte= lemon juice -> Citric acid is the active ingrediant(sp).
Volta (late 18th century scientist) used a stack for his batteries-
copper disk, paper disk soaked in acid, zinc disk, copper disk, paper ....
they were advanced technology for the time.
Gerald Edgar
gwe3409@atc.boeing.com
"The opinions expressed in this communication may not reflect those of my
employer"
From: st1my@rosie.uh.edu (Stich, Christian E.)
Subject: Motorola XC68882RC33 and RC50
Organization: University of Houston
Lines: 17
Distribution: world
NNTP-Posting-Host: rosie.uh.edu
Keywords: Motorola, FPU, 68882, 68030, 33/50 MHz, problems (FPU exception)
News-Software: VAX/VMS VNEWS 1.41
I just installed a Motorola XC68882RC50 FPU in an Amiga A2630 board (25 MHz
68030 + 68882 with capability to clock the FPU separately).  Previously
a MC68882RC25 was installed and everything was working perfectly.  Now the
systems displays a yellow screen (indicating a exception) when it check for
the presence/type of FPU.  When I reinstall an MC68882RC25 the system works
fine, but with the XC68882 even at 25 MHz it does not work.  The designer
of the board mentioned that putting a pullup resistor on data_strobe (470 Ohm)
might help, but that didn't change anything.  Does anybody have some
suggestions what I could do?  Does this look like a CPU-FPU communications
problem or is the particular chip dead (it is a pull, not new)?
Moreover, the place I bought it from is sending me an XC68882RC33.  I thought
that the 68882RC33 were labeled MC not XC (for not finalized mask design).
Are there any MC68882RC33?
Thanks
Christian
From: peter.m@insane.apana.org.au (Peter Tryndoch)
Subject: Telephone On Hook/Off Hok
Lines: 17
AllMichael CovingtonTelephone on hook/off hok
MC>From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
MC>Organization: AI Programs, University of Georgia, Athens
MC>Aye, there's the rub -- if you draw enough current to light an LED, th
MC>equipment at the phone company will think you've gone off hook.
MC>In the on-hook state you're not supposed to draw current.
Ok lets have some calculation here: Going by Australian standards, which I
presume might be similar to other countries ( If not, lets have some
input) a phone uses 600ohm to loop a 48V line = 80mA. A standard LED
drains 20mA. So what is the actual loop current required for an "off hook"
indication, do you know?
Cheers
Peter T.
From: peter.m@insane.apana.org.au (Peter Tryndoch)
Subject: What'S A Good Ic For Rs23
Lines: 13
AllTall Cool OneWhat's a good IC for RS23
TC>From: rky57514@uxa.cso.uiuc.edu (Tall Cool One )
TC>Organization: University of Illinois at Urbana
TC>I'm looking for an IC that will convert RS232 voltage levels to TTL vo
TC>levels.  Something relatively inexpensive would be nice, too.  Anyone
TC>a suggestion??  Thanks.
Try a Maxim "MAX232CPE" 8 pin dil, converts 5V to 12V for 232commms.
What a clever little gizmo!
Peter T.
From: peter.m@insane.apana.org.au (Peter Tryndoch)
Subject: Swr Meter For Cb Radios
Lines: 28
AllThe Devil ReincarnateSWR meter for CB radios
TD>From: ssave@ole.cdac.com (The Devil Reincarnate)
TD>Organization: CDAC, WA
TD>What
TD>is a good choice for a CB? 1/4 or 1/8 wave?
TD>  I read the installation instructions on a 1/4 wave antenna,
TD>and they suggested that I use an SWR to tune it at channel 12
TD>and channel 32 for a minimum reading.  Question is, why channel
TD>12 and 32?
The best antenna is one that will let out the most wave (probably not the
best explanation, but the rest makes sense) A one wave will cancell itself
out (BTW no such beastie) . The best is a 1/2 wave antenna, followed by
1/4, then 1/8 etc.
As for SWRing in, what you actually do is trim the antenna to the correct
length for the specific wavelength you will be transmitting on. Since the
wavelength varies with the channel you use, then it's recommended to SWR
in using the middle channel of those you are going to use.
Anyway in the beginning of CB's, all new antennas had to be SWR'ed in,
nowdays manufactures trim the antennas almost spot on, so that there's not
much point in SWRing. Then again you may be a fanatic and whish to do it
anyway.
Cheers
Peter T.
From: peter.m@insane.apana.org.au (Peter Tryndoch)
Subject: What'S Exactly In A Flour
Lines: 32
AllMartin MccormickWhat's Exactly in a Flour
MM>From: martin@datacomm.ucc.okstate.edu (Martin McCormick)
MM>Organization: Oklahoma State University, Stillwater, OK
MM>	What sort of lamp is the little glass bulb found inside the
starter?
MM>It sort of reminds me of a NE2 neon lamp.  Starters appear open when m
MM>with an Ohm meter so the little lamp is either a neon or has a capacit
MM>in series with it.
MM>
MM>	I have seen these things all my life, but never read a really good
MM>description of what is happening inside that little can.
Do you know what a bi-metallic strip is?
Just in case: it is two strips of different metals bonded together, which
when heated bend to one side (check out the blinker globe in your
christmas tree lights).
So when you turn on the power, this causes the bulb to work like a neon,
heating up and shorting out, thus providing a loop to power the heaters in
the main tube. When the tube fires, insufficient current runs through the
starter to keep the heat up and the bi-metalic strip straightens out
(O/C).
BTW, I too thought that they were nothing more than a small neon, so one
day when the neon in my sisters digital (flip the metal squares type)
clock broke (flimsy leads), I replaced it with one from a starter. Well
powering up made a bit of a mess of the clock!
Cheers
Peter T.
From: peter.m@insane.apana.org.au (Peter Tryndoch)
Subject: Dmm Advice Needed
Lines: 28
AllMartin EmdeDMM Advice Needed
ME>From: mce5921@bcstec.ca.boeing.com (Martin Emde)
ME>Organization: Boeing
ME>
ME>I an currely in the market for a DMM and recently saw an add
ME>for a Kelvin 94 ($199).  Does anyone own one of these or some
ME>other brand that they are extremely happy with.  How do the
ME>small name brands compare with the Fluke and Beckman brands?
ME>I am willing to spend ~$200 for one.
ME>
ME>Any help is greatly appreciated. (please email)
ME>
ME>-Martin
If you are going to use one where it counts (eg:aviation, space scuttle,
etc) then I suggest you go and buy a Fluke (never seen a Beckman), however
for every other use you can buy a cheapie. I have a metex which is some
made up name, as I have seen the same DMM with other brand names on it, I
bought it about 4 yrs ago for Aus$125.00 (convert that to US and you see
that it's definetly a cheapie.) So far it has proved to be accurate, taken
moderate abuse, and has many features on it (CAP, FREQ,Transistor check,
etc). I am very happy with it and would definetly not buy a fluke just for
the name. Hope this helps.
Cheers
Peter T.
From: R_Tim_Coslet@cup.portal.com
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: The Portal System (TM)
Distribution: world
Lines: 41
In article: <1qlg9o$d7q@sequoia.ccsd.uts.EDU.AU>
swalker@uts.EDU.AU (-s87271077-s.walker-man-50-) wrote:
>I really don't know where to post this question so I figured that
>this board would be most appropriate.
>I was wondering about those massive concrete cylinders that
>are ever present at nuclear poer sites. They look like cylinders
>that have been pinched in the middle. Does anybody know what the
>actual purpose of those things are?. I hear that they're called
>'Cooling Towers' but what the heck do they cool?
Except for their size, the cooling towers on nuclear power plants
are vertually identical in construction and operation to cooling
towers designed and built in the 1890's (a hundred years ago) for
coal fired power plants used for lighting and early electric railways.
Basicly, the cylindrical tower supports a rapid air draft when
its air is heated by hot water and/or steam circulating thru a network
of pipes that fill about the lower 1/3 of the tower. To assist cooling
and the draft, water misters are added that spray cold water over the
hot pipes. The cold water evaporates, removing the heat faster than
just air flow from the draft would and the resulting water vapor is
rapidly carried away by the draft. This produces the clouds frequently
seen rising out of these towers.
That slight pinch (maybe 2/3 of the way up the tower) is there because
it produces a very significant increase in the strength and rate of
the air draft produced, compared to a straight cylinder shape.
The towers are used to recondense the steam in the sealed steam
system of the power plant so that it can be recirculated back to the
boiler and used again. The wider the temperature difference across
the turbines used in the power plant the more effecient they are and
by recondensing the steam in the cooling towers before sending it
back to the boilers you maintain a very wide temperature difference
(sometimes as high as 1000 degrees or more from first stage "hot"
turbine to final stage "cold" turbine).
R. Tim Coslet
Usenet: R_Tim_Coslet@cup.portal.com
technology, n.  domesticated natural phenomena
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Subject: Re: Telephone On Hook/Off Hok
Nntp-Posting-Host: aisun3.ai.uga.edu
Organization: AI Programs, University of Georgia, Athens
Lines: 26
In article <734953838.AA00506@insane.apana.org.au> peter.m@insane.apana.org.au (Peter Tryndoch) writes:
>MC>Aye, there's the rub -- if you draw enough current to light an LED, th
>MC>equipment at the phone company will think you've gone off hook.
>MC>In the on-hook state you're not supposed to draw current.
>
>Ok lets have some calculation here: Going by Australian standards, which I
>presume might be similar to other countries ( If not, lets have some
>input) a phone uses 600ohm to loop a 48V line = 80mA. A standard LED
>drains 20mA. So what is the actual loop current required for an "off hook"
>indication, do you know?
Up to 60 microamperes  =   on hook
Over something like 10 mA  = off hook
In between = defective line, and the phone company comes looking
for leaky insulation.
--
:-  Michael A. Covington, Associate Research Scientist        :    *****
:-  Artificial Intelligence Programs      mcovingt@ai.uga.edu :  *********
:-  The University of Georgia              phone 706 542-0358 :   *  *  *
:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :  ** *** **  <><
From: rmf@bpdsun1.uucp (Rob Finley)
Subject: Re: RAMs &ROMs with ALE latches (for 8051's)
Organization: Harris Allied Broadcast Div., Quincy, IL
Lines: 22
Intel also makes some neat memory and peripheral chips:
Old technology (early 1980's)
8155  ram plus IO (slow ram as I recall)
8755  eprom plus IO (expensive and slow)
Intel does make Eproms with built in address latches.
I fear that you would need a very flexible and up-to-date eprom
programmer to write to them.
give them a call.  I am not able to locate their memory products book
yet.
Sigh...  Now, who borrowed it...
Robert
From: haynes@cats.ucsc.edu (Jim Haynes)
Subject: Re: History question
Organization: University of California; Santa Cruz
Lines: 30
NNTP-Posting-Host: hobbes.ucsc.edu
In article <1qnroe$d1n@usenet.INS.CWRU.Edu> wb8foz@skybridge.scl.cwru.edu (David Lesher) writes:
>An now-deceased prof told us willing students about a project he had
>worked on during WWII.
>
>They needed a mega-power PA with very clear audio quality. The purpose
>was to bellow at refugees from aircraft.
>
>Their solution was a giant compressed-air source, and a horn with
>parallel shutters worked by a small audio system. I think he said it
>worked very well, thus the War Dept. cancelled the project ;_}.
Gee, I got the idea from somewhere that devices like this were in common
use in WWII, so that commanders on board ships could bellow at the troops
landing on a beach, for example.
Which reminds me of an anecdote from the mid-60s.  At a communications
conference a Marine Corps communications officer said he didn't care
much for all the spread-spectrum multi-access expensive communication
systems that people were talking about at the time; what he wanted
was a kilowatt broadcast transmitter on the ship and a $4.95 Japanese
transistor radio stuck in the ear of every Marine hitting the beach.
--
haynes@cats.ucsc.edu
haynes@cats.bitnet
"Ya can talk all ya wanna, but it's dif'rent than it was!"
"No it aint!  But ya gotta know the territory!"
Meredith Willson: "The Music Man"
From: gt0869a@prism.gatech.EDU (WATERS,CLYDE GORDON)
Subject: Re: History question
Organization: Georgia Institute of Technology
Lines: 23
In article <2775@snap> paj@uk.co.gec-mrc (Paul Johnson) writes:
>This is vague, so I am posting it in case anyone else knows more.
>
>I recall reading of a phonograph which used mechanical amplification.
>Compressed air was squirted out of a valve which was controlled by the
>pickup.  The result was noisy and distinctly lo-fi, but much louder
NASA and related agencies apparently used this same principles to create
the loudest reported reproduced sound. They used an "analog" electrically
controlled valve to control the flow of air across a horn throat. If I
remember correctly it was called a "modulated air blast transducer". There
were reports of the thing being able to produce 106 dB @ 80 Hz @ 10 mile
distance, communicate directly with fighter pilots @ 5000 ft, etc.
Regards,
Gordon.
--
WATERS,CLYDE GORDON-BME '93-Georgia Institute of Technology Atlanta Ga.
"Out of the mountain of despair, we can hew the stone of hope"- MLK Jr.
uucp:	  ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!gt0869a
Internet: gt0869a@prism.gatech.edu
From: myers@hpfcso.FC.HP.COM (Bob Myers)
Subject: Re: subliminal message flashing on TV
Organization: Hewlett-Packard, Fort Collins, CO, USA
Lines: 18
> Hi.  I was doing research on subliminal suggestion for a psychology
> paper, and I read that one researcher flashed hidden messages on the
> TV screen at 1/200ths of a second.  Is that possible?  I thought the
> maximum rate the TV was even capable of displaying images was 1/30th
> of a second.  (or 1/60th of a second for an image composed of only odd
> or even scan lines)
You are correct; the fastest "complete" image that could be presented on
TV would be one field, which is 1/60 of a second (approximately).  Of course,
the phrase "TV screen" is often thrown around in reference to any CRT
display, so perhaps this researcher wasn't using normal TV rates.  Might
even be a vector ("strokewriter") display, in which case the lower limit
on image time is anyone's guess (and is probably phosphor-persistence limited).
Bob Myers  KC0EW   Hewlett-Packard Co.      |Opinions expressed here are not
Systems Technology Div.  |those of my employer or any other
myers@fc.hp.com    Fort Collins, Colorado   |sentient life-form on this planet.
From: myers@hpfcso.FC.HP.COM (Bob Myers)
Subject: Re: Scope questions
Organization: Hewlett-Packard, Fort Collins, CO, USA
Lines: 31
> 	If my life depended on it, I'd say that it's a scope that
> 	uses long-persistance phosphor to keep the successive
> 	taces on the screen for some unit of time - "store" them.
> 	Do I get to live?
We'll let you live, but just this once....
There's more to a real "storage" scope than just a long-persistence
phosphor.  Actually, the phosphor ISN'T usually anything special at all;
what makes a storage tube work is a screen placed just *behind* the phosphor,
which becomes charged as the electron beam intially "writes" the trace.
With the trace now written to the screen, a separate low-level "flood"
electron gun keeps the image lit by exciting those areas of phosphor
which are next to the "written" areas on the storage screen.  There are
some problems with this - the resolution is limited compared to a non-storage
tube, and the stored trace tends to "bloom" with time.
Of course, this is pretty much obsolete technology, done in by the current
digital scopes which use raster-scan displays and keep everything in a
frame-buffer memory anyways.
> / Filip "I'll buy a vowel" Gieszczykiewicz. | Best e-mail "fmgst+@pitt.edu"  \
^^^^^^^^^^^^^^^^^^
Ah, yes - from the same people who brought you that amazing new reading
program that's sweeping Eastern Europe: "Hooked on Consonants!" :-)
Bob Myers  KC0EW   Hewlett-Packard Co.      |Opinions expressed here are not
Systems Technology Div.  |those of my employer or any other
myers@fc.hp.com    Fort Collins, Colorado   |sentient life-form on this planet.
From: kolstad@cae.wisc.edu (Joel Kolstad)
Subject: Re: Dmm Advice Needed
Article-I.D.: doug.1993Apr17.020555.6004
Organization: U of Wisconsin-Madison College of Engineering
Lines: 14
In article <734953838.AA00510@insane.apana.org.au> peter.m@insane.apana.org.au (Peter Tryndoch) writes:
>
>If you are going to use one where it counts (eg:aviation, space scuttle,
>etc) then I suggest you go and buy a Fluke (never seen a Beckman), however
>for every other use you can buy a cheapie.
My Beckman died a few days ago, thanks do about a 4 or 5 foot drop onto a
lab table.  !@#!@$#!@$@#$  Probably not indicative of anything, but I've
already filled out the requisition for a Fluke 87. :-)
Oh yeah, and sometimes our measurements here do count.  Not often, but often
enough that I want at least _one_ good meter!
---Joel Kolstad
From: Wayne Alan Martin <wm1h+@andrew.cmu.edu>
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: Senior, Electrical and Computer Engineering, Carnegie Mellon, Pittsburgh, PA
Lines: 60
Distribution: world
NNTP-Posting-Host: po2.andrew.cmu.edu
In-Reply-To: <79694@cup.portal.com>
Excerpts from netnews.sci.electronics: 16-Apr-93 Re: What do Nuclear
Site's .. by R_Tim_Coslet@cup.portal.
> From: R_Tim_Coslet@cup.portal.com
> Subject: Re: What do Nuclear Site's Cooling Towers do?
> Date: Fri, 16 Apr 93 21:27:21 PDT
>
> In article: <1qlg9o$d7q@sequoia.ccsd.uts.EDU.AU>
>         swalker@uts.EDU.AU (-s87271077-s.walker-man-50-) wrote:
> >I really don't know where to post this question so I figured that
> >this board would be most appropriate.
> >I was wondering about those massive concrete cylinders that
> >are ever present at nuclear poer sites. They look like cylinders
> >that have been pinched in the middle. Does anybody know what the
> >actual purpose of those things are?. I hear that they're called
> >'Cooling Towers' but what the heck do they cool?
>
> Except for their size, the cooling towers on nuclear power plants
> are vertually identical in construction and operation to cooling
> towers designed and built in the 1890's (a hundred years ago) for
> coal fired power plants used for lighting and early electric railways.
>
> Basicly, the cylindrical tower supports a rapid air draft when
> its air is heated by hot water and/or steam circulating thru a network
> of pipes that fill about the lower 1/3 of the tower. To assist cooling
> and the draft, water misters are added that spray cold water over the
> hot pipes. The cold water evaporates, removing the heat faster than
> just air flow from the draft would and the resulting water vapor is
> rapidly carried away by the draft. This produces the clouds frequently
> seen rising out of these towers.
>
> That slight pinch (maybe 2/3 of the way up the tower) is there because
> it produces a very significant increase in the strength and rate of
> the air draft produced, compared to a straight cylinder shape.
>
> The towers are used to recondense the steam in the sealed steam
> system of the power plant so that it can be recirculated back to the
> boiler and used again. The wider the temperature difference across
> the turbines used in the power plant the more effecient they are and
> by recondensing the steam in the cooling towers before sending it
> back to the boilers you maintain a very wide temperature difference
> (sometimes as high as 1000 degrees or more from first stage "hot"
> turbine to final stage "cold" turbine).
>
>                                         R. Tim Coslet
>
> Usenet: R_Tim_Coslet@cup.portal.com
>         technology, n.  domesticated natural phenomena
Great Explaination, however you left off one detail, why do you always
see them at nuclear plants, but not always at fossil fuel plants.  At
nuclear plants it is prefered to run the water closed cycle, whereas
fossil fuel plants can in some cases get away with dumping the hot
water.  As I recall the water isn't as hot (thermodynamically) in many
fossil fuel plants, and of course there is less danger of radioactive
contamination.
Wayne Martin
From: mvanmeet@ua.d.umn.edu (Mike VanMeeteren)
Subject: Re: electronic odometers (was: Used BMW Question ..... ???)
Organization: University of Minnesota, Duluth
Lines: 28
NNTP-Posting-Host: ua.d.umn.edu
In article <C5HHKo.1ry@vu-vlsi.ee.vill.edu> mobasser@vu-vlsi.ee.vill.edu (Bijan Mobasseri) writes:
>> There are two simple procedures for alterating any odometer.
>>
>>1. Mechanical driven odometer:
>>    Remove the speedo cable from the transmission.
>>    Attach a drill and run at max speed until the speedo turns over.
>>    Continue until the desired mileage is reached.
>====================================
>Admittedly an irrelavent question:for how long should the drill be running?
>
>Bijan
A verrrrrry long time, like on the order of days.  I had the pleasure of
doing that once (playing with the speedo cable) and with my B&D heavy duty at
full speed (600 rpm) all the speedo ever got up to was 30 MPH.  Now if you go
a high speed drill and ran it at say 4000 rpm, you could get 200 MPH out of
it.  (If you speedo doesn't burn out.)  Anyways, to roll a 100000 Mile
odometer would take 22 days or so.  Much easier just to take the speedo
apart.
Thought I'd share.  BTW, all this info was obtained legally  :-)
--
(~)~)~) o /)  _     Computer Lesson One: There is no "any" key, alternate keys
/ / / / /_) /_)                         are <shift>,<ctrl>,<caps lock>,<alt>
/ / (_(_/ (_/\_                          and sometimes <tab>.
mvanmeet@ub.d.umn.edu                                -consultant at lab
From: schmidt@auvax1.adelphi.edu
Subject: Grounding power wiring, was Re: a question about 120VAC outlet wiring
Lines: 163
Nntp-Posting-Host: auvax1
Organization: Adelphi University, Garden City NY
There has been quite a bit of discussion about house wiring and grounding
practices here.  A few points need to be clarified:
The Equipment GROUNDING conductor, Green, green with a yellow stripe, bare, or
the metal sheath or pipe of SOME wiring methods, is used as a safety ground, to
carry fault currents back to the circuit breaker panel, and to limit the
voltage on the metal case of utilization equipment or other metal objects.  It
should never (except for a few exceptions to be discussed later) carry the
normal operating current of a connected load.  Some equipment has filters in
the power supply which may cause some slight current flow through the grounding
conductor.
Much communications or audio equipment is sensitive to noise or slight voltages
on the grounding conductor, and may require special wiring of the grounding
conductors to provide reliable operation  ("orange" outlets are often used for
this, with insulated grounding conductors wired back to the panel box, and in
many cases back to the service.  Anyone installing such a system should read
both the section on grounding in the National Electric Code and publications on
installing quiet isolated ground systems.  The code requires the insulated
grounding conductors (green wires) to run with the current carrying conductors
back to the panel box, and, if required, back all the way to the service
entrance , where it is bonded to the service ground (water pipe or rod)  Many
of these systems are installed illegally or unsafely, where they do not provide
a safe ground or a quiet ground or either.
The GROUNDED conductor of a circuit, often called the NEUTRAL, which is
referred to in the code as the "identified" conductor and is supposed to be
white or natural grey.  This conductor is supposed to be connected to ground in
most electrical systems at a single point, generally at the service entrance
panel.  This connection is through the Main Bonding Jumper.  (In many household
service panels, the main bonding jumper is actually a bonding screw which
attaches the neutral busbar to the case of the panel)
The Grounded conductor (neutral) is generally a current carrying conductor.  In
the case of a 120 volt circuit it is one of the two conductors completing the
circuit from the panel to the load device.
Since the grounded conductor (neutral) is only connected to the grounding
conductor (bare or green) at the service entrance, if the load is any distance
from the service and draws any significant current, there will be a small but
measurable voltage between the grounded and grounding conductors at the load,
under normal operating conditions.  If you should (incorrectly) connect the
grounded (neutral) conductor to the grounding conductor at the load, some of
the neutral current will flow instead through the grounding conductor.  Since
there will now be current flowing through the grounding conductor, it will also
no longer be quite at ground potential at the load end.  If the load equipment
has a metal case, which is connected to the grounding conductor through the "U"
ground plug, the metal case is now also no longer quite at ground potential.
The difference (under normal, non short-circuit conditions) may be only a few
tenths of a volt, but it could also be a volt or two.  This normally does not
present a shock hazard.
HOWEVER, if you let the metal case of the grounded equipment come into contact
with an independently grounded object such as a water or gas pipe, a radiator,
a metal air conditioning duct or such, part of the neutral current will try to
flow through this aalternate ground path.  If the contact is not solid, you
will get a significant arc (a low voltage, but possibly moderate current arc)
Under the wrong conditions, this arcing could start a fire.  It is possible in
some cases that the sneak ground current   could also flow through a wire of
inadequate size, causing it to overheat.
With the incorrect non single-point grounding of the neutral, if there is a
short circuit from hot to neutral, the high short circuit current which may
flow will cause a much higher voltage on the grounding conductor, which
increases the possibility for shock or fire.
Also if you incorrectly multiply connect the neutral and ground, the voltage on
the ground system is seen as noise bu computer or audio equipment, often
causing malfunction.  I have spent some hours tracking down such shorts in
technical facilities where they were inducing severe hum into equipment.
The Neutral is usually bonded to the ground at the distribution transformer as
well as at the service entrance of each dwelling.  This is done primarily for
lightning protection, so that induced lightning currents have a short path back
to ground, and also to assure that the currents drawn by shorts to grounded
objects like pipes draw enough current to trip circuit breakers or blow fuses
quickly.  The bad side of this is that not all the neutral current from the
dwelling goes through the neutral wire back to the transformer.  Some of it
flows through the grounding electrode (water pipe, etc.) this may cause
corrosion in the pipes and possibly in things like underground fuel oil tanks,
and it may also cause measurable AC magnetic fields due to the large loop
between the "hot" conductors in the service and the neutral current in the
water pipe and ground.  There are those who feel these fields may be unhealthy.
(don't flame ME on this, I'm just telling you where the field comes from, not
it's health effect, as far as I'm concerned, the jury is still out on this.)
Note that the bonding jumper is only installed at the main panel, NOT at any
sub distribution panels.  This is one reason why it is illegal to run service
entrance cable with the sheath used as a neutral to a sub panel, you must have
a seperate insulated conductor for the neutral.  The sheath can be used in this
application only as the groundING conductor.  If the neutral is bonded to the
grounding conductor in the sub panel, say by forgetting to remove the bonding
screw, all the grounding conductors of the loads on that panel will be above
ground, with the possible problems listed above.
The code makes exceptions for ranges and dryers, as well as feeds from one
building to another.  In the cases of the range and dryer, the neutral may be
used as the equipment ground under certain conditions, instead of a seperate
wire.  Every time the code is revised, these exceptions come up for review.
These exceptions were, in fact the first required safety grounds, in the days
before U ground outlets and such.  The appliance manufacturers don't want to
have to redesign their ranges and driers, and the contractors don't want to
have to run four wire cable (with four fairly heavy, expensive wires) in place
of three wire to the appliances.  No question it would be safer with seperate
neutrals to the stove, but the neutral current is low for most burner settings
(since most current is in the 220 volt "hots" except at some low settings, the
wires are large gauge, and there are few reported cases of injury or damage.
So far, the exceptions have survived. In the case of feeds between buildings,
it's primarily for lightning protection.
People doing wiring should be aware what is and what isn't a legal grounding
conductor.  Obviously, the bare wire in "romex" 'with ground' is.  Anywhere
there is a green wire installed, such as in a portable cord, that is a good
grounding conductor.  The sheath of BX clamped in BX connectors in metal boxes
is a legal grounding conductor (in the US). (BX has an aluminum band run under
the steel sheath to lower the resistance of the sheath.  You can just cut this
aluminum band off at the ends, you don't have to bond it to anything, it does
its job by touching every turn of the BX sheath.) Conduit or EMT (thinwall
tubing) is generally a legal grounding conductor, but may require a bonding
locknut where it enters a box or panel, particularly for larger pipes.
"Greenfield" (looks like big BX, but you pull your own wires in the empty
sheath after you run it) is NOT a legal grounding conductor, as it doesn't have
the aluminum band to bond it, and the spiral steel has too much resistance and
inductance.  You have to run a seperate green grounding conductor inside the
greenfield.
"Wiremold" is also not a legal grounding conductor, as the paint on the boxes
often prevents good contact, and the "feed" to the wiremold extension is often
from a box in the wall that may not be well connected to the first wiremold
box.  I have personally discovered cases where the entire run of wiremold and
the cases of everything plugged into all the outlets on the run were "hot" with
120 volts (Why do I get a shock every time I touch my computer and the radiator
here in the office?) because there was no ground wire in the wiremold and one
of the outlets had shorted to the edge of the wiremold box.  You must run a
ground wire back in the wiremold from the outlets at least to the first box in
the original wiring (conduit, BX, etc.) where you can "bond" the wire to the
box with a screw, bnding clip, or whatever.
On another issue, while you should ground the green wire/lug on GCFI outlets
when ever there is a place to ground them, it is legal in the NEC to use them
without a ground if no ground is available.  It is better to have the
protection of the Ground fault interrupter than no protection if you don't
install it.  The interrupter doesn't depend on the ground to trip.  It is
desirable to connect the ground if available, because if the ground is
connected, the interrupter will trip as soon as a faulty device is plugged in,
whereas without the ground, it will not trip until someone or something
provides a ground path.  For those questioning the legal use of ungrounded
GCFI's, read in the NEC, 210-7 (d) exception. (This is the 1990 code, my '93
code is in the city, but I know the rule hasn't changed.  It might be
renumbered though.)
We have only touched the surface concerning grounding ;-} , there is much more
to this subject, but most of you have fallen asleep by now.
John
--
*******************************************************************************
John H. Schmidt, P.E.              |Internet: schmidt@auvax1.adelphi.edu
Technical Director, WBAU           |Phone--Days     (212)456-4218
Adelphi University                 |       Evenings (516)877-6400
Garden City, New York 11530        |Fax-------------(212)456-2424
*******************************************************************************
From: zklf0b@wwnv28.hou.amoco.com (Fergason)
Subject: Re: what to do with old 256k SIMMs?
Organization: Amoco Production
Lines: 21
In article <1ql7ug$i50@sunb.ocs.mq.edu.au> johnh@macadam.mpce.mq.edu.au (John Haddy) writes:
>In article <120466@netnews.upenn.edu>, jhaines@eniac.seas.upenn.edu (Jason Haines) writes:
>|>
>|> 	I was wondering if people had any good uses for old
>|> 256k SIMMs.  I have a bunch of them for the Apple Mac
>|> and I know lots of other people do to.  I have tried to
>|> sell them but have gotten NO interest.
>|>
>|> 	So, if you have an inovative use (or want to buy
>|> some SIMMs  8-) ), I would be very interested in hearing
>|> about it.
>
>The most practical use I've seen for them is as key ring ornaments :-)
>
>JohnH
I used a bunch as weights, when building a model airplane.  Hung them
on the stringers, across the stringer, or whatever.  Worked pretty well.
Kelly
From: tchannon@black.demon.co.uk (Tim Channon)
Subject: Re: Can I use a CD4052 analog multiplexer for digital signal
Reply-To: tchannon@black.demon.co.uk
Distribution: world
X-Mailer: cppnews $Revision: 1.20 $
Organization: null
Lines: 19
> As the subject says - Can I use a 4052 for digital signals?  I don't see
> why it couldn't handle digital signals, but I could be wrong.  Anyone have
> any advice?  Thanks.
Yes.
I use 74HC4066 and others commerically for this purpose so rest assured it
works fine. In one case I route bit serial digital audio using these and it
is difficult to see any signal degradation at all which surprised me given
some pretty fast edges. HC4066 is spec'd at something like -3dB @ 200MHz into
50 ohms. The more complex types are generally a little slower and more
resistive.
Plain 4000 series are not so good at handling 5v logic.
Remember that the output load is seen by the input device.
TC.
E-mail: tchannon@black.demon.co.uk or tchannon@cix.compulink.co.uk
From: mpaul@unl.edu (marxhausen paul)
Subject: Re: Whats wrong with my cordlessphone?
Organization: University of Nebraska--Lincoln
Lines: 8
Distribution: world
NNTP-Posting-Host: unlinfo.unl.edu
I've also found that the electronic starters on these "instant-on"
compact fluourescent lamp fixtures kick out interference that nukes
my cordless phone.  (I can hear it in my guitar amplifier, too...)
--
paul marxhausen .... ....... ............. ............ ............ ..........
.. . .  . . . university of nebraska - lincoln .  . . .. . .  .. . . . . . . .
.     .    .  .   .     .   .  .    .   .  .   .    .   .  grace .   .    .  .
.         .       .      .        .        .      .        .   happens .
From: cs000rdw@selway.umt.edu (Richard D Warner)
Subject: UART-CPU-ROM-RAM subsystem
Keywords: cheap, low-cost, small $$$
Organization: University of Montana
Lines: 21
This is a followup post to something I've written previously.  Several
people responded with good information, but I don't think I communicated
exactly what I am looking for.
I'm working on a custom I/O device that will communicate with a host
via RS-232.  My custom circuitry will use an 80C186EB or EC CPU and require
about 64K of RAM (preferably FLASH RAM).  In looking around, I see that lots
of people have engineered UART-CPU-ROM-RAM subsystems that are ready to be
interfaced to your custom I/O devices.  It's been done so much, that it
would be best if I can avoid reinventing a system.  It just needs to use
an 80C186 (or 188) CPU, and be able to load a program from the host then
transfer control to that program.  Well, there's one other thing the ROM
needs to know how to do.  It should have routines to send and receive bytes
to/from the host, that utilize the hardware control lines (DTR,RTS,DTS,CTS).
Everything I've seen is in the $200.00 and up range.  That's too much for
this application.  I need something around $100.00.  The CPU has the UART
built-in, so you're only looking at a few chips.  Does anyone know a
company that markets a good board in this range, or some public domain
circuitry I can use?  Thanks in advance for the info.
Rich
From: ianmc@spartan.ac.BrockU.CA (Ian McPherson)
Subject: Re: chip / chipset for code 39 barcode?
Organization: Brock University, St. Catharines Ontario
X-Newsreader: TIN [version 1.1 PL9]
Lines: 26
LLBGB@utxdp.dp.utexas.edu wrote:
: Distribution: usa
: Reply-To: lihan@ccwf.cc.utexas.edu
: While I'm on the net bugging everyone, is there such a thing as a chip
: or chipset to decode Code 39 barcode?  I ask for a couple of reasons --
: mainly I want a reasonably compact encoding scheme to write information
: on magstripe cards and Code 39 appears to be about right.  (If the 'right'
: way to do it is something else, and it's reasonably easy, can someone let
: me know?)
: I might not get a chance to reply too quickly to this or my earlier post,
: but I'll get to them within a couple days, I think ..
: thanx everyone!  <BGB>  lihan@ccwf.cc.utexas.edu
Hewlett Packard has a series of barcode decoder ICs HBCR-1800, HBCR-2000,
and HBCR-2010 and they support 3of9  extended 3of9  interleaved 2of5
and UPC codes. The 2000 and 2010 pieces add codabar and code 128.
These chips support HP's barcode wands and slot readers.
An 1800 + a HEDS-3050 wand run about $150 CDN .
Ian.
From: rbn@apple.com (Robert B. Neville)
Subject: Oscilliscopes for sale
Organization: Apple Computer, Inc., Cupertino, California
Lines: 37
NNTP-Posting-Host: apple.com
Recently I posted two oscilliscopes for sale. One has sold, the other is
still available:
Used, good condition:
Hitachi V-422 40MHz Dual-Channel Portable Analog Oscilliscope
o 1mV/div
o DC offset
o alternate magnification (10x magnified & non-magnified
waveform)
o VERT mode trigger
o TV sync separation circuit
List price      $910.00 (...and the price Fry's electronics just
quoted!) :-(
Sells for       $699.99 (JDR MicroDevices current price)
$745.95 (Products International)
Your price used $425.00 obo
...I haven't gotten an offer at the asking price, so 'obo' applies...
I also have a 'broken' version of the scope which sold:
JDR 2000 20MHz Dual-Channel Portable Analog Oscilliscope
o 5mV/div
o Component Tester (resistors/caps/diodes/coils)
o TV video sync filter
o z-axis input (intensity modulation)
'Broken' means: The CRT produces a nice, bright trace, but the trace does
not correspond to the input signal. My guess is it's repairable but more
than a simple calibration problem...but I honestly have not tried to
calibrate the scope or otherwise fix it. It's 'as-is'.
I paid $60 for it in its current state (I bought it thinking I'd repair it,
using the 'good' scope for side-by-side comparison...since I've sold the
'good' scope, the 'bad' one doesn't do me much good) and I'd like to recoup
that amount. As above, I'll accept offers and take the best one.
I'd prefer a local (Bay Area, California) buyer, so (a) I don't have to
ship it and (b) she or he can examine the scope prior to purchase.
rbn@apple.com
From: nagle@netcom.com (John Nagle)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: NETCOM On-line Communication Services (408 241-9760 guest)
Lines: 42
Wayne Alan Martin <wm1h+@andrew.cmu.edu> writes:
>Excerpts from netnews.sci.electronics: 16-Apr-93 Re: What do Nuclear
>Site's .. by R_Tim_Coslet@cup.portal.
>> From: R_Tim_Coslet@cup.portal.com
>> Subject: Re: What do Nuclear Site's Cooling Towers do?
>> Date: Fri, 16 Apr 93 21:27:21 PDT
>>
>> In article: <1qlg9o$d7q@sequoia.ccsd.uts.EDU.AU>
>>         swalker@uts.EDU.AU (-s87271077-s.walker-man-50-) wrote:
>> >I really don't know where to post this question so I figured that
>> >this board would be most appropriate.
>> >I was wondering about those massive concrete cylinders that
>> >are ever present at nuclear poer sites. They look like cylinders
>> >that have been pinched in the middle. Does anybody know what the
>> >actual purpose of those things are?. I hear that they're called
>> >'Cooling Towers' but what the heck do they cool?
>Great Explaination, however you left off one detail, why do you always
>see them at nuclear plants, but not always at fossil fuel plants.  At
>nuclear plants it is prefered to run the water closed cycle, whereas
>fossil fuel plants can in some cases get away with dumping the hot
>water.  As I recall the water isn't as hot (thermodynamically) in many
>fossil fuel plants, and of course there is less danger of radioactive
>contamination.
Actually, fossil fuel plants run hotter than the usual
boiling-water reactor nuclear plants.  (There's a gripe in the industry
that nuclear power uses 1900 vintage steam technology).  So it's
more important in nuclear plants to get the cold end of the system
as cold as possible.  Hence big cooling towers.
Oil and gas fired steam plants also have condensers, but they
usually are sized to get the steam back into hot water, not most of the
way down to ambient.  Some plants do cool the condensers with water,
rather than air; as one Canadian official, asked about "thermal
pollution" de-icing a river, said, "Up here, we view heat as a resource".
Everybody runs closed-cycle boilers.  The water used is
purified of solids, which otherwise crud up the boiler plumbing when
the water boils.  Purifying water for boiler use is a bigger job than
cooling it, so the boiler water is recycled.
John Nagle
From: sundar@fiber-one.ai.mit.edu (Sundar Narasimhan)
Subject: how much would a Tektronix 2465A oscilloscope fetch
Reply-To: sundar@ai.mit.edu
Organization: MIT Artificial Intelligence Laboratory
Lines: 7
NNTP-Posting-Host: fiber-one.ai.mit.edu
Hi: I'd like to know how much the foll. equipment will fetch in the used
equipment market (without manuals or other accessories):
1. Tektronix 2465 scope
2. Tektronix 2465A scope
3. Tektronix 1240 logic analyser
Thanks much for your help.
From: rubin@cis.ohio-state.edu (Daniel J Rubin)
Subject: Re: what to do with old 256k SIMMs?
Organization: The Ohio State University Dept. of Computer and Info. Science
Lines: 18
NNTP-Posting-Host: diplodocus.cis.ohio-state.edu
>>	I was wondering if people had any good uses for old
>>256k SIMMs.  I have a bunch of them for the Apple Mac
>>and I know lots of other people do to.  I have tried to
>>sell them but have gotten NO interest.
How hard would it be to somehow interface them to some of the popular
Motorola microcontrollers.  I am a novice at microcontrollers, but I am
starting to get into them for some of my projects.  I have several 256k
SIMMs laying around from upgraded Macs and if I could use them as "free"
memory in one or two of my projects that would be great.  One project that
comes to mind is a Caller ID device that would require quite a bit of RAM
to store several hundered CID records etc...
- Dan
--
Daniel Joseph Rubin     rubin@cis.ohio-state.edu
GO BENGALS!      GO BUCKS!
From: eabyrnes@vela.acs.oakland.edu (Ed Byrnes)
Subject: Getting rid of screen wiggles?
Organization: Oakland University, Rochester MI.
Lines: 15
Distribution: world
NNTP-Posting-Host: vela.acs.oakland.edu
My monitor display has a bad case of the wigglies. I have a good ground. I
live in an old house and I have replaced much of the wiring. I have two
EMI filters on the computer, the monitor plugs into the computer. When
fluorescent lights are on upstairs, the display jiggles, when motors run
in the house, the display jiggles, when incandescent lights are on in the
kitchen the display jiggles.  I could bring a separate line from the
breaker box, and use it only for the computer, would this do it? EMI
doesn't only travel the 110 volt line though. Should I shield the back of
the monitor? Ground a grid or plate?
Your expertise is appreciated. Thanks very much!  Ed Byrnes
--
*---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---*
|   Ed Byrnes   FAX:  313-651-7392           eabyrnes@vela.acs.oakland.edu  |
|   Kensington Academy & Oakland University    Rochester, MI North America  |
*---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---*
From: al@qiclab.scn.rain.com (Alan Peterman)
Subject: Fluke For Sale (was DMM Advice Needed)
Keywords: Fluke 8062A $115
Article-I.D.: qiclab.1993Apr17.202510.1992
Organization: SCN Research/Qic Laboratories of Tigard, Oregon.
Lines: 13
I have a spare Fluke 8062A.  This is a true RMS digital meter with
4.5 digit display.  It's in "average" condition (been used) but
works fine - which is what Fluke's are all about.   BTW - according
to the fellow who designed these meters, they can be converted to 8060A
function by clipping a jumper, and adding the 2 extra switches..
Like I said $115 seems fair - these sell for $300+ new.
--
Alan L. Peterman                                 (503)-684-1984 hm & work
al@qiclab.scn.rain.com
It's odd how as I get older, the days are longer, but the years are shorter!
From: mcole@spock (COLE)
Subject: 8051 Microcontroller
Organization: New Mexico State University
Lines: 3
NNTP-Posting-Host: spock.nmsu.edu
I would like to experiment with the INTEL 8051 family.  Does anyone out
there know of any good FTP sites that might have compiliers, assemblers,
etc.?
From: cjp1@aber.ac.uk (Christopher John Powell)
Subject: Fujitsu 8" HDD
Keywords: M2321K, M2322K, Fujitsu, Microdisk (-:
Organization: University of Wales, Aberystwyth
Lines: 23
I have a Fujitsu M2322K which has been removed (I believe) from a digital
X-Ray machine (takes X-Ray pictures without film).  The Fujitsu part number
is B03B-4745-B002A.
I have obtained some data on the device, it is 8-inch winchester-type
of 168 megabyte capacity (though I was told it was over 800 megabytes).
However, there is very little information on the interface standard used.
It appears to use two balanced-line connections, but what each connection
corresponds to I know not. One connection is a 30-way IDC, the other a
60-way IDC.
If anyone has any information on this device, I would be most grateful
if you could provide it.
Thanks.
Chris Powell.
--
+------------------------------------------------------------------------+
|  THE MAN FROM :  #####  #######  | JANET    : cjp1@uk.ac.aber          |
|                 #     #     _#   | Internet : cjp1@aber.ac.uk          |
|                 #     #  _#      | NYX      : cpowell@nyx.cs.du.edu    |
From: billq@ms.uky.edu (Billy Quinn)
Subject: Re: Radio Shack Battery of the Month Club
Organization: University Of Kentucky, Dept. of Math Sciences
Lines: 18
donrm@sr.hp.com (Don Montgomery) writes:
>Radio Shack has canceled their "Battery of the Month" Club.  Does
>anyone know why?
>They say they'll honor existing cards in customer hands, but no new
>cards will be issued.
I was told that this is an environmental based move.  I was also told that
there will be 'somthing' else to replace the battery club.  Like maybe
the 360K floppy club ;-).
We'll see ....
--
*-----------------------------------------------------------------------*
*	Bill Quinn			billq@ms.uky.edu		*
*-----------------------------------------------------------------------*
From: iisakkil@gamma.hut.fi (Mika Iisakkila)
Subject: Re: what to do with old 256k SIMMs?
In-Reply-To: rubin@cis.ohio-state.edu's message of 17 Apr 1993 14:05:06 -0400
Nntp-Posting-Host: gamma.hut.fi
Organization: Helsinki University of Technology, Finland
<1qpgsiINN31p@diplodocus.cis.ohio-state.edu>
Lines: 15
rubin@cis.ohio-state.edu (Daniel J Rubin) writes:
>How hard would it be to somehow interface them to some of the popular
>Motorola microcontrollers.
Not hard, you can do the refreshing and access cycles by software, but
this hogs most of the available CPU cycles on a low-end controller.
I've seen some application note from Philips that used one of their
8051 derivatives as a printer buffer, with up to 1MB of dynamic ram
that was accessed and refreshed with software bit-banging.
Another alternative would be to use one of those nice DRAM controller
chips that "create static RAM appearance" and all that, but they may
be too expensive to make it worthwhile.
--
Segmented Memory Helps Structure Software
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Public-domain circuits in commercial applications
Organization: U of Toronto Zoology
Lines: 31
In article <1993Apr13.164924.2606@wuecl.wustl.edu> dp@cec1.wustl.edu (David Prutchi) writes:
>Can circuits found in electronics magazines (with no patent disclaimer)
>be used legally as subcircuits of a commercial unit ?
There are two issues here:  copyright and patent.
The magazine article's contents are copyrighted, and may not be reproduced,
translated, etc., without the copyright holder's permission.  However, this
does not cover the *ideas* expressed, only the form of expression.  Copying
their circuit diagram or PC-board pattern is copyright infringement.  But
it's unlikely that they could stretch copyright far enough to claim that
the circuit design itself is copyrighted.  So long as you draw your own
diagrams and lay out your own boards, copyright shouldn't be an issue.
Patents are different.  The author does *not* have to give you any warning
that the design is covered by patent (although it would be sensible for
him to do so).  In fact, it's possible that *he* was infringing on someone
else's patent without realizing it.  Ignorance of the patented status is
not a defence against infringement, although it might reduce the damages
a court would award.
However... unless there was something seriously novel about the circuit,
almost certainly it is "obvious to one skilled in the art" and therefore
unpatentable.  Routine engineering is not patentable; patents (in theory)
cover only inventions, ideas that are genuinely new.
Caution:  I am not a lawyer.  Consulting a professional would be wise if
significant amounts of money are at stake.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
- Kipling           |  henry@zoo.toronto.edu  utzoo!henry
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Public-domain circuits in commercial applications
Organization: U of Toronto Zoology
Lines: 16
In article <C5GE03.LIF@athena.cs.uga.edu> mcovingt@aisun3.ai.uga.edu (Michael Covington) writes:
>... Patent law says you can build anything
>you want to, for your own personal noncommercial use...
I'm not up on the details of US patent law, but I think this is incorrect.
There is a "reasonable use" exemption for *copyright*.  There is none for
*patents*.  The exemptions from patent licensing are quite narrow; R&D work
is exempt but personal use is not.  That is, it's okay to experiment with
a patented idea, but not to put it to practical use (e.g. to improve your
stereo), even if it's only your own private practical use.
Of course, it is unlikely that discreet personal use will ever be detected
or that you will ever be sued over it.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
- Kipling           |  henry@zoo.toronto.edu  utzoo!henry
From: fculpepp@norfolk.vak12ed.edu (Fred W. Culpepper)
Subject: CAD Program for Electronics?
Organization: Virginia's Public Education Network (Norfolk)
Lines: 19
I am making a search for a CAD program that does a decent job
of making schematic drawings.  The program needs to be in
MS-DOS, Windows if possible.
What I want the CAD program to do is to draw diagrams by
dragging elements onto the screen, and in this the elements
needed are as diverse as vacuum tubes to ICs (case with pins).
It also needs to have provision for adding legends to the
components as well as their values.  In other words I want to
produce quality drawings.  Printout would be to either 24 pin
dot-matrix and/or Laser Printer.
If you know of such a CAD program that is of reasonable cost,
please respond.
Fred W. Culpepper
OLD DOMINION UNIVERSITY (Retired)
fculpepp@norfolk.vak12ed.edu
---
From: suwanto@iastate.edu (zapper)
Subject: Re: 2SC1096, 2SA634 specs?
Organization: Iowa State University, Ames IA
Lines: 35
>Could some kind soul post me the max power/voltage/current ratings of
>2SC1096 and 2SA634 transistors, their conductance types and pinouts.
>They are used in the sweep portion of a TV set.
2SC1096
Maximum Ratings:
VCBO = 40V
VCEO = 30V
IC   = 3A
PC   = 10W (T=25C)
ICBO max = 1uA
VCB = 30V
COB = 55pF
at Q-point VCE=5, IC=1A --> hfe = 100
2SA634
Maximum Ratings:
VCBO = -40V
VCEO = -30V
IC   = -3A
PC   = 10W (T=25C)
ICBO max = -1uA
VCB = -30V
COB = 75pF
at Q-point VCE = -5V, IC = -1A --> hfe = 100
That's all i can get from my data book, hope that helps.
suwanto@iastate.edu
From: ulan@ee.ualberta.ca (Dale Ulan)
Subject: Re: what to do with old 256k SIMMs?
Nntp-Posting-Host: eigen.ee.ualberta.ca
Organization: University Of Alberta, Edmonton Canada
Lines: 28
rubin@cis.ohio-state.edu (Daniel J Rubin) writes:
>How hard would it be to somehow interface them to some of the popular
>Motorola microcontrollers.  I am a novice at microcontrollers, but I am
>starting to get into them for some of my projects.  I have several 256k
>SIMMs laying around from upgraded Macs and if I could use them as "free"
>memory in one or two of my projects that would be great.  One project that
>comes to mind is a Caller ID device that would require quite a bit of RAM
>to store several hundered CID records etc...
Assuming 68HC11...
In expanded muxed mode, you *could* do it. Much easier if you get a DRAM
controller IC. The MMI 673102 could be used to implement this, or you
could use a counter and a huge multiplexer to provide row/column/refresh
address multiplexing. The thing with DRAMs is that they require wierd
timing, address multiplexing, and refresh.
Actually, if you wanted to use a 68008 IC, you could look at AN897, which
has a neat controller built in. There is also the 683xx, I think one
of those has the DRAM controller built in. This one is for the 6664
DRAM, however, the 41256 has only one more address line, adding only
another component or so. The 256k SIMMs are basically 8 or 9 41256
DRAM chips (or their equivalent in fewer packages).
It *can* be done, just takes a bit of logic design. I'm actually
about to do it using a 65C02P3 chip... I've got 8 256k simms... that's
2 megabytes on my Apple //e... (used to be in my '386).
From: dannyb@panix.com (Daniel Burstein)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: PANIX Public Access Unix, NYC
Lines: 27
<lots of pretty good stuff about how the huge towers near most nuclear
power plants are there to cool the used steam back into near ambient
temperature water deleted>
>>water.  As I recall the water isn't as hot (thermodynamically) in many
>>fossil fuel plants, and of course there is less danger of radioactive
>>contamination.
>       Actually, fossil fuel plants run hotter than the usual
>boiling-water reactor nuclear plants.  (There's a gripe in the industry
>that nuclear power uses 1900 vintage steam technology).  So it's
>more important in nuclear plants to get the cold end of the system
>as cold as possible.  Hence big cooling towers.
as a point of info, some of the early nuclear power plants in this
country used the fission pile as a first stage to get the water hot, and
then had a second stage -fossil fuel- step to get the water (actually
steam) VERY HOT.
I remember seeing this at Con Edison's Indian Point #1 power plant,
which is about 30 miles north of NYC, and built more or less 1958.
dannyb@panix.com
(all the usual disclaimers apply, whatever they may be)
From: mustafa@seas.smu.edu (Mustafa Kocaturk)
Subject: How starters work really
Keywords: fluorescent bulb starter neon
Nntp-Posting-Host: turbo_f.seas.smu.edu
Organization: SMU - School of Engineering & Applied Science - Dallas
Lines: 28
In article <734953838.AA00509@insane.apana.org.au> peter.m@insane.apana.org.au (Peter Tryndoch) writes:
>
>So when you turn on the power, this causes the bulb to work like a neon,
>heating up and shorting out, thus providing a loop to power the heaters in
>the main tube. When the tube fires, insufficient current runs through the
>starter to keep the heat up and the bi-metalic strip straightens out
>(O/C).
Imprecise. This description
1. ignores the role of the ballast,
2. misrepresents the heating effects in the starter.
The bimetalic strip cools down immediately after the contacts
short circuit, because the neon discharge stops, and much less
heat is generated from the I^2R loss in the metal as compared to
the neon discharge.
The starter contacts open before the tube fires.  Actually,
the tube fires as a result of the back-emf generated in the ballast
because of this immediate opening of the starter's contacts.
A capacitor is connected in parallel with the contacts to prevent
excessive arcing during the firing.  The neon reionizes but does not draw
sufficient current to prevent firing of the tube itself.
--
Mustafa Kocaturk   mustafa@seas.smu.edu  EE Dept., Room 305A, Caruth Bldg.
Home: 214-706-5954  Office: 214-768-1475  SMU Box 753190, Dallas, TX 75275
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: 74ACT???
Organization: U of Toronto Zoology
Lines: 86
In article <1qhrq9INNlri@crcnis1.unl.edu> mpaul@unl.edu (marxhausen paul) writes:
>OK, what's a quick rundown on all the 7400 series variations?  We're
>repairing something with a 74ACT00 on it and the question arises, "well,
>do  i really need the ACT part?"  Flipping through Digi-Key I see
>ALS, AS, C, HC, AC, ACQ, ACT, HCT, ACHT, HCTLS...
Here's something I posted about this a few years ago.  It's not fully
up to date with all the new variations (some of which are just different
manufacturer's synonyms):
------
In practical terms, ignoring the technological details, this is my view
of the families (NB I am not a giant corporation, which influences my
views on things like availability and backward compatibility):
74	The original.  Speed good, power consumption fair.  Effectively
obsolete now; use 74LS or later, except for a *very* few oddball
functions like 7407 which are hard to find in newer families.
74H	Modification of 74 for higher speed, at the cost of higher
power consumption.  Very obsolete; use 74F.
74L	Modification of 74 for lower power, at the cost of lower speed.
Very obsolete; use CMOS.
74S	Later modification of 74 for even higher speed, at some cost in
power consumption.  Effectively obsolete; use 74F.
74LS	Combination of 74L and 74S, for speed comparable to 74 with lower
power consumption.  Best all-round TTL now, widest variety of
devices.
74F	Fast as blazes, power not too bad.  The clear choice for high
speed in TTL.  Availability and prices generally good.
74AS	Failed competitor to 74F, although a few 74AS parts do things
that are hard to find in 74F and thus are still useful.
74ALS	Possible replacement for 74LS.  Generally souped up.  Still fairly
new, availability and prices possibly a problem.
74C	Fairly old family, CMOS devices with TTL pinouts.  Competed with
4000 series, not too successfully.  Obsolete; use 4000 or newer
CMOS 74 families.
4000	(Thrown in as the major non-74 non-ECL logic family.)  The old CMOS
family, still viable because of *very* wide range of devices, low
power consumption, and wide range of supply voltages.  Not fast.
Very forgiving and easy to work with (beware static electricity,
but that comment applies to many other modern logic families too).
There are neat devices in this family that exist in no other.  The
clear choice when speed is not important.
74HC	A new attempt at 74-pinout CMOS.  Fast compared to old CMOS, power
consumption often lower than TTL.  Possibly a good choice for
general-purpose logic, assuming availability and affordability.
CMOS logic levels, *not* TTL ones.  Beware very limited range of
supply voltages compared to older CMOS, also major rise of power
consumption at faster speeds.
74HCT	74HC with TTL logic levels.  Much the same comments as 74HC.  Read
the fine print on things like power consumption -- TTL compatibility
in CMOS involves some compromises.
10K	(Thrown in for speed freaks.)  The low end of ECL.  Various sources
claim that it is *easier* to work with than super-fast TTL for
serious high-speed work.  Less forgiving, though:  read and follow
the rules or it won't work.  Availability to hobbyists limited,
can be expensive.
100K	(For real speed freaks.)  Hot ECL.  Harder to handle than 10K, and
inconvenient packages.  Much more useful datasheets, however.
As for compatibility between families:  the 74 families (except 74C and
74HC) are all more or less logic-level compatible, but how many 74X devices
you can drive from one 74Y output varies enormously with X and Y.  You just
have to read the specs and do the arithmetic.  74C and 74HC are compatible
with the others with a bit of hassle.  4000 compatibility can be a bit of
hassle or a lot of hassle depending on what supply voltage 4000 is using.
10K or 100K to anything else is considerable hassle.
Me?  I use 4000 and 74LS with a sprinkling of 74F.  74HC[T] and 10K are
interesting but I haven't used either significantly yet.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
- Kipling           |  henry@zoo.toronto.edu  utzoo!henry
From: jgd@dixie.com (John De Armond)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: Dixie Communications Public Access.  The Mouth of the South.
Keywords: Nuclear
Lines: 33
swalker@uts.EDU.AU (-s87271077-s.walker-man-50-) writes:
>I was wondering about those massive concrete cylinders that
>are ever present at nuclear poer sites. They look like cylinders
>that have been pinched in the middle. Does anybody know what the
>actual purpose of those things are?. I hear that they're called
>'Cooling Towers' but what the heck do they cool?
>I hope someone can help
The actual hourglass is hollow and is designed to generate a draft,
exploiting the venturi effect.  Around the base of the hourglass is a
ring of water towers.  Warm river water, coming from the steam condenser
in the plant, is sprayed over louvres.  The draft being pulled through
the tower cools the water by both evaporation and convection.  The
sensible heat extracted from the cooling water is the driving force for
draft generation.
It should be noted that the hourglass-shaped cooling towers are used on
both fossile and nuclear plants.  It should also be noted that at
locations where water is plentiful, the cooling towers are only used part
time, when the discharge temperature would exceed some release limit.
It was once thought that the warm discharge water was damaging to fish.
Fishermen know that is thoroughly incorrect.  Nontheless, stringent,
usually state, regulations remain in some instances.  Since it typically
takes 60,000 hp worth of pumping to move the volume of water needed
to cool a 1000 MWe plant, the cost of using the towers is not insignificant.
--
John De Armond, WD4OQC               |Interested in high performance mobility?
Performance Engineering Magazine(TM) | Interested in high tech and computers?
Marietta, Ga                         | Send ur snail-mail address to
jgd@dixie.com                        | perform@dixie.com for a free sample mag
Lee Harvey Oswald: Where are ya when we need ya?
From: victor@inqmind.bison.mb.ca (Victor Laking)
Subject: Re: making copy of a Video tape
Keywords: video
Organization: The Inquiring Mind BBS  1 204 488-1607
Lines: 35
hooperw@spot.Colorado.EDU (Wayne Hooper) writes:
> victor@inqmind.bison.mb.ca (Victor Laking) writes:
>
> >You are experiencing what is called Macrovision.  It is the protection
> >that they use on the video tapes.  There are two ways around this that I
> >know of.  First of all, you can try using a different VCR to copy onto.
> >It is the input of the VCR that reacts to the protection so sometimes
> >just switching the two VCRs around will take care of it.  Some models
> >just don't react to it.
>
> Does this also affect the viewing of tapes ? I have had problems with
> a couple of rented tapes; they were virtually unviewable. I fiddled
> with the tuning, tracking and vertical hold but it was no good.
>
It sounds like your TV is one of the ones that also reacts to the video
protection.  (Poor you!)
The Macroscrubber from Radio Electronics removes the protection so you
souldn't have any more problems.  However, if you use the method of
copying it from one VCR to another where the second VCR doesn't react to
the protection, you will end up with a duplicate tape, including the
protection.
One thought comes to mind about your problem...  When playing the tape
for viewing, are you feeding the signal from the source VCR through an
extra device before going to the TV?  If you feed it through a second VCR
first, that is your problem.  As to other devices such as converters, I
don't know if they would react or not.  Just to be safe, you might want
to make sure that you have NOTHING between the VCR and TV.
victor@inqmind.bison.mb.ca
The Inquiring Mind BBS, Winnipeg, Manitoba  204 488-1607
From: cyberman@toz.buffalo.ny.us (Cyberman)
Subject: CRT driver transistors
Lines: 28
X-Maildoor: WaflineMail 1.00r
Device........ LT1839   @ IC (mA)..... 50
V(BR)CEO (V).. 70       CCB (pF)...... 2.5
V(BR)CBO (V).. 120      VCE (V)....... 15
IC (mA) max... 300      Polarity...... NPN
hFE min....... 20       Package....... 79-04
hFE max....... 60       Material...... Metal
fT (GHz)...... 1        Price (100+)..
Device........ LT5839   @ IC (mA)..... 60
V(BR)CEO (V).. 65       CCB (pF)...... 1.5
V(BR)CBO (V).. 80       VCE (V)....... 10
IC (mA) max... 300      Polarity...... PNP
hFE min....... 15       Package....... 79-04
hFE max....... 60       Material...... Metal
fT (GHz)...... 1.5      Price (100+)..
@ VCE (V)..... 10
Anyone know of a source for these parts (other than straight from
Motorolla)?  I need 4 Lt1839's and 2 Lt5839 I've tried standard
and they said "We are out!"
Stephen Cyberman@Toz.Buffalo.NY.US
Mangled on Fri  04-16-1993  at 13:50:28
... If there's one thing I can't stand, it's intolerance.
---
* Blue Wave/QWK v2.12 *
From: cyberman@toz.buffalo.ny.us (Cyberman)
Subject: Re: Analog switches/Balan
Lines: 31
X-Maildoor: WaflineMail 1.00r
{Michael Fulbright} said
"Analog switches/Balanced"
to <All> on 04-15-93  01:08
MF> I am trying to build a synchronous demodulator and I've hit a snag.
MF> In my application I want to be able to change the gain of an
MF> op amp amplifier from 1 to -1, controlable via a digital input.
MF> The most obvious way I've come up with is to use analog switches
MF> to adjust the gain of the op amp. The only analog switch I have
MF> experience with it the 4066. Unfortunately I want to switch an
MF> AC signal which goes from about -5V to 5V, and the 4066 is only
MF> for positive signals.
How about using a 4053 it has a seperate ground for the
analog outputs.  It would get you 3 bits.
MF> Another part which caught my eye was the Analog Devices AD630. This
MF> is a balanced demodulator which appears to fill exactly the need I
MF> have. The data sheet was somewhat skimpy on application notes. Could
MF> someone comment on using this chip for the following application?
Or how about a multiplying D/A convertor?  This is
essentiallty what you are makeing.
Stephen Cyberman@Toz.Buffalo.NY.US
Mangled on Fri  04-16-1993  at 13:36:11
... Catch the Blue Wave!
---
* Blue Wave/QWK v2.12 *
From: v064mb9k@ubvmsd.cc.buffalo.edu (NEIL B. GANDLER)
Subject: Need diode model for PSpice
Organization: University at Buffalo
Lines: 15
News-Software: VAX/VMS VNEWS 1.41
Nntp-Posting-Host: ubvmsd.cc.buffalo.edu
Im designing a circuit with just a silicon diode. I dont need
to modify any of the parameters. But the problem will not accept the following
statement
.model diode D
The pspice book I have is terrible. I would appreciate any help.
Neil Gandler
_____________________________________________________________________________
Gandler Electronics
Home Automation & electronic design technology
_____________________________________________________________________________
From: mlee@eng.sdsu.edu (Mike Lee)
Subject: Wire-Amperage table needed
Organization: San Diego State University Computing Services
Lines: 5
NNTP-Posting-Host: eng.sdsu.edu
X-Newsreader: TIN [version 1.1 PL9]
Does anyone has a table about the size of the wire to the amount of current it can carry.  Probably in the 1-15amp range.  My friend is interested in converting a Mazda into an electric car.  Needed information for estimation.  Thanks in advance.
p.s. any info on electric will be greatly appreaciated.
From: gsulliva@enuxha.eas.asu.edu (Glenn A Sullivan)
Subject: Re: making copy of a Video tape
Summary: Here is Go-Video
Organization: Arizona State University
Lines: 14
In article <136390006@hpcuhe.cup.hp.com>, pi@hpcuhe.cup.hp.com (Paul Ilgenfritz) writes:
>
> I think the Go Video dual cassette machines do a direct tape to tape copy
> which transfers Macrovision to the copy.  I you can find one of these, it
> would be worth a try.
Go-Video machines used in HQ2 mode will copy even the MacroVision.
Go-Video phone number (602)998-3400.
Ask for sales department. Since the state of Arizona does not go on
Daylight Savings time, we effectively are in Pacific time zone.
Allen Sullivan
Designing various stuff for GO-Video
From: wb8foz@skybridge.SCL.CWRU.Edu (David Lesher)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: NRK Clinic for habitual NetNews abusers - Beltway Annex
Lines: 19
Reply-To: wb8foz@skybridge.scl.cwru.edu (David Lesher)
NNTP-Posting-Host: skybridge.scl.cwru.edu
Others said:
# >       Actually, fossil fuel plants run hotter than the usual
# >boiling-water reactor nuclear plants.  (There's a gripe in the industry
# >that nuclear power uses 1900 vintage steam technology).  So it's
# >more important in nuclear plants to get the cold end of the system
# >as cold as possible.  Hence big cooling towers.
When the utility gave up on that Cinnci, OH plant (Zimmer?) and
announced they were going to convert it to a coal-fired scheme, the
turbines were already in place, and they were the low-temp type. So the
plan was: Install a SECOND set of high temp turbines, and feed the
low-temp ones with the output of the new ones.
Never saw anything more on this. Did they ever really build it?
--
A host is a host from coast to coast..wb8foz@skybridge.scl.cwru.edu
& no one will talk to a host that's close............(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
From: wb8foz@skybridge.SCL.CWRU.Edu (David Lesher)
Subject: Re: 74ACT???
Organization: NRK Clinic for habitual NetNews abusers - Beltway Annex
Lines: 29
Reply-To: wb8foz@skybridge.scl.cwru.edu (David Lesher)
NNTP-Posting-Host: skybridge.scl.cwru.edu
Others said:
# 74S	Later modification of 74 for even higher speed, at some cost in
# 	power consumption.  Effectively obsolete; use 74F.
#
# 74LS	Combination of 74L and 74S, for speed comparable to 74 with lower
# 	power consumption.  Best all-round TTL now, widest variety of
# 	devices.
#
# 74F	Fast as blazes, power not too bad.  The clear choice for high
# 	speed in TTL.  Availability and prices generally good.
I hate to disagree w/ a fellow as smart as Henry, but...
A few years back, I worked on a project using lots of high-speed
stuff.  (My part was slow & parallel, whew.) The mild-mannered designer
working on the fast (serial) stuff cussed & swore at 74F all the time.
It was the Harry Reams of TTL. One ultra-tiny power line glitch, one
hickup, one eyeblink across the board, and bang - the F had
toggled/counted/whatevered.  At times he swore it would count even
without any 5 volt supply ;-} You can guess what the "F" stood for....
They would do anything to push S or work around it to avoid using F. I
don't think I'd consider using F to replace S unless the consequences
were *fully* understood.......
--
A host is a host from coast to coast..wb8foz@skybridge.scl.cwru.edu
& no one will talk to a host that's close............(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
From: ah499@cleveland.Freenet.Edu (John Daniels)
Subject: HELP!: Apple II Expansion Chassis by Mountain Computer
Organization: Case Western Reserve University, Cleveland, Ohio (USA)
Lines: 25
NNTP-Posting-Host: slc10.ins.cwru.edu
I recently bought an apparantly complete Expansion Chassis by Mountain
Computer Inc.  It consists of a box with 8 Apple ][+ compatible slots,
powersupply brick, interface card and ribbon cable to attach it to the computer
to be expanded.  There was also included a small card with empty sockets on top
and pins on the bottom that looks like it would plug into the ][+ motherboard
somewhere after pulling a chip.  There's an empty socket also on the interface
card and a short 16-pin DIP jumper like the ones used with ][+ language cards.
This technological marvel came with no docs and I haven't a clue as how to hook
this thing up.  If anyone has docs and/or users disk of any sort for this I
could really use copies of them or at least some help.
I need to know:
o How to orient the ribbon cable between the card and the chassis.
o How to attach the short cable from the motherboard to the card
and if the small card is used.
o The purposes of the various jumper-pins on the card (it has more
of those than my CMS SCSI card!)
thanks                                          John Daniels
ah499@cleveland.freenet.edu
From: surfer@world.std.com (Internet Surfer)
Subject: 6551A and 6551 compatibility
Organization: Boston Computer Society / ISIG
Lines: 10
Does any one know if the 6551 is timing/pin compatible with the 6551..
It seems the 6551 has in iheirent bug with cts/rts handshaking and i need
a suitable pin replacement to put in my serial card... possibly a buffered
version perhaps?
--
jolt@gnu.ai.mit.edu	      |    Its not impossible, just improbable
johnp@pro.angmar.uucp         |            (Zaphod Beeblbrox)
bl298@cleveland.freenet.edu   |   N1NIG@amsat.org (Being a Ham is so grand)
From: griffin@camelot.bradley.edu (Mark Valentine)
Subject: HELP: 20ma current loop to RS232 converter needed.
Summary: I need a device that will convert 20ma current loop to RS232.
Keywords: 20,current,loop,converter,rs232
Nntp-Posting-Host: camelot.bradley.edu
Organization: Bradley University
Distribution: usa
Lines: 10
Where can I buy or build a device that will convert 20 ma
current loop signals to RS232 voltages?  I know some old terminals
came with that option, but none of the ones I own have that.  Anyway,
I want to connect a computer to this old industrial computer to use
the computer with communications software as a console instead of
an old DecWriter.  Please e-mail me if you have any info that would
point me in the right direction.
From: chris@alien.saar.de (Christian Reisel)
Distribution: world
Organization: Chaos live
Subject: Re: What do Nuclear Site's Cooling Towers do?
Reply-To: chris@alien.saar.de
X-Software: HERMES GUS 1.10 Rev. Mar  3 1993
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Lines: 82
In <C5L5x0.KJ7@vcd.hp.com>, John Eaton writes:
[...]
>During the nuclear fission reaction the uranium fuel can get hot enough
>to melt. When this happens the liquid uranium is pumped to the cooling
>tower where it is sprayed into the air. Contact with the cool outside air
>will condense the mist and it will fall back to the cooling tower floor.
>There it is collected by a cleaning crew using shop vacs and is then
>reformed into pellets for reactor use the next day.
>
>Cooling towers are a lot taller than they really need to be. Power companies
>are forced to make them that tall by some enviromental law that requires the
>raw uranium emisions to be held to under 1%. This law is now under attack
>by lawyers arguing that the 1% should be measured at the edge of the property
>rather than the edge of the cooling tower. Eliminating this law will save
>power companies thousands of dollars in concrete costs for new nukes.
>
>John Eaton
>!hp-vcd!johne
>
I think you posted your article 15 days too late :-)) April 1st is over.
I don't like nuclear powerplants but i think it's not fair to tell such
"storys" about them. OK ?
Let me try to explain what that tower is used to:
-1st. Even the modernst nuclear powerplant is only a simple steam-engine.
It has an hightech "boiler" but the rest is still verry verry
conventional. And if you've already visited any condensation-
powerstation you'l have seen the cooling towers too.
If you look at any good book about thermophysics you'll find
a chapter about the "CARNOT-process" which describes how to
get energy from a temperature difference ! And that is the reason
for cooling towers too !!! You only can get energy if you've an
temperature gradient. That means that you have steam on the one
side and need to cool down the steam 'till you get water
again on the other side if you want to get aprox. 30% of the
energy you (or better the uranium) brought into the water to
let it boil. If you only have hot steam on the one and "cold"
steam on the other side you'll loose much more of the energy.
And so they cool down the steam to get at least the 30% of
energy that carnot will give them.
The cooling towers are for cooling the steam !
The vapor you'll see is NOT the steam of the main core circulation,
because that steam is radioactive ! The circulation is divided in
AT LEAST 2 circuits connected about heat exchangers to prevent
radioactive pollution of the environment !
-2nd. OK, the main core IS hot, but even in the modernst HighTemperature-
Reactors (HTR) they only run at ~800 deg celsius. This is still
verry far away from uraniums melting point which is somewhere
around 2000 deg. celsius ! But you'll have lot's of problems with
the boiler's steel. That's because at this temperature the
metal is attacked by steam and will corrode verry fast.
This is only for BWR's. The new He cooled reactors have temperatures
up to 1200 deg. celsius. But this is only experimental.
-3rd. I personaly think that nuclear waste should be as low as ever
possible because the dose you get will accumulate about the
years. Today 1 mRem and next year 0.5 mRem won't be 0.75 mRem
at all. It accumulates and even in 80 years you'll still have
1.5 mRem. And i'm not interested in glowing in the night and
getting children with 2 heads. This is my point of view.
Only my 0.02$ !
Christian Reisel
student of electronic sciences
--
Christian Reisel, Goldammerweg 2, W-6601 Buebingen, Germany
Voice        +49 6805 22179 Fax & Email  +49 6805 22179
PGP PubKey:
--------------------------------------------------------------
begin 777 pcr.pub
MF5L`P`"S*Q%296ES96PL($-H<FES=&EA;OX!P7R5'F0QY1Q_.=+SY(;DZ0L:6
MMO(]]0`=K?/VH[U-"6MX]7G\-MF]/;&`H5KL/%,M\$:89^5FI6;W:$T$;9M!Q
$+04`$0`=@
``
end
From: adykes@jpradley.jpr.com (Al Dykes)
Subject: help: How to reduce the RPMs of a Boxer fan ?
Organization: Unix in NYC
Distribution: na
Lines: 16
I need to reduce the speed of a Boxer fan by about 30-50%. I recall
reading somewhere that the right capacitor in series will do it.
If this isn't a case of brain fade, can someone suggest the cap value ?
The specifics; It's a real Boxer Fan (tm). The label says 115 V, .2 amps.
Al Dykes
--------
adykes@jpr.com
From: baden@sys6626.bison.mb.ca (baden de bari)
Subject: **] A/D board quiry:
Organization: System 6626 BBS, Winnipeg Manitoba Canada
Lines: 21
On an A/D board I've got, I'm using the A/D lines.  It measures
the voltages properly, ie: with a 7v power supply it reg's 7v and with
5v, it reg's 5v.  Problem is when I've got the input voltage, and I wish
to lower it via a resistor.  The sensitivity of the board is so great
that I can triger it with holding the 5/7v wire in one hand, and touch
the probe and it will register the full input voltage.  A 1m resistor
only lowers voltage by .1v so this is not too feesable.
What could the problems be and what else could I use
to lower the input voltage?  (btw I've got it grounded correctly)
_________________________________________________
Inspiration  |   ___                             |
comes to     |  \   o  baden@sys6626.bison.mb.ca |
those who    | (  ^  ) baden@inqmind.bison.mb.ca |
seek the     |   /-\      =] Baden de Bari [=    |
unknown.     |                                   |
-------------------------------------------------
From: alee@ecs.umass.edu
Subject: Need to find out number to a phone line
Lines: 13
Greetings!
Situation:  I have a phone jack mounted on a wall.  I don't
know the number of the line.  And I don't want
to call up the operator to place a trace on it.
Question:   Is there a certain device out there that I can
use to find out the number to the line?
Thanks for any response.
Al
From: frankh@scraps.uucp (Frank Holden KA3UWW)
Subject: Re: What's a good IC for RS232 -> TTL signals??
Organization: None
Lines: 34
In <C57zsC.9FL@news.cso.uiuc.edu> rky57514@uxa.cso.uiuc.edu (Tall Cool One ) writes:
>I'm looking for an IC that will convert RS232 voltage levels to TTL voltage
>levels.  Something relatively inexpensive would be nice, too.  Anyone have
>a suggestion??  Thanks.
Well it looks as if Digi-Key sells a chip with the number ICL232 that does what
you want.  They are selling it for about $3.50...
Hope this helps...
Frank
--
**************************************************************************
* Customer asked "What's that thing?".                                   *
* I answered chuckling "Well, it's a highly technical, sensitive         *
* instrument I use in computer repair! Being a layman, you probably      *
* cann't grasp exactly what it does. I call it a B.F.H.....              *
* Frank W. Holden - KA3UWW - "The Radio Doctor"                          *
* - - - - - - - - - - - - - - - - - | - - - - - - - - - - - - - - - - -  *
* SnailMail:                        | Inter-Net:                         *
* 685 Addison St.                   | frankh@scraps.pittsburgh.sgi.com   *
* Washington, Pa. 15301-5601        | Packet:ka3uww@n3idi.#wpa.pa.usa.na *
**************************************************************************
DISCLAIMER:<disclaimer.h> - I confess, you did it!!!
--
**************************************************************************
* Customer asked "What's that thing?".                                   *
* I answered chuckling "Well, it's a highly technical, sensitive         *
From: ulan@ee.ualberta.ca (Dale Ulan)
Subject: Re: Need to find out number to a phone line
Nntp-Posting-Host: eigen.ee.ualberta.ca
Organization: University Of Alberta, Edmonton Canada
Lines: 21
alee@ecs.umass.edu writes:
>Greetings!
>
>        Situation:  I have a phone jack mounted on a wall.  I don't
>                    know the number of the line.  And I don't want
>                    to call up the operator to place a trace on it.
>        Question:   Is there a certain device out there that I can
>                    use to find out the number to the line?
>        Thanks for any response.
>                                                    Al
There usually is a way, however, often, telephone companies like to
keep all of their internal numbers private. Depends on your exchange.
Any modern electronic switching equipment usually have voice synth
lines that echo the number you called from. The line service guys use this
to make sure they connect up the right pairs of lines.
From: bryan@philips.oz.au (Bryan Ryan)
Organization: Philips Public Telecommunications Systems, Melbourne, Australia
Subject: Re: RAMs &ROMs with ALE latches (for 8051's)
Lines: 28
spp@zabriskie.berkeley.edu (Steve Pope) writes:
>In article <1qg98sINNokf@sheoak.ucnv.edu.au> jeff@redgum.ucnv.edu.au (j. pethybridge) writes:
>>	Hello again,
>> I asked this a year ago, but i am still looking.
>> I am getting sick of having to use a HC373
>Jeff, just use the damned 373.   Sure, there are oddball
>latched memory chips, but do you really want to use them?
>Sorry if I'm pedantic but: design your circuit using
>reasonably available parts, and move on to more important
>problems.
We're looking at a series of chips by WSI, the PSD3xx series. They have
_mega_ address decoding logic on them, various ROM sizes (upto 1Mbit),
various RAM sizes (upto 16 K), and 19 I/O ports which can be chip select
lines, I/O or the buffered address lines.
Cute chip, 44 pin PLCC package.
Second sourcing may be a problem though :-(
Bryan Ryan, VK3TKX
Melbourne, Australia
bryan@philips.oz.au
From: cyberman@toz.buffalo.ny.us (Cyberman)
Subject: Re: what to do with old 2
Lines: 33
X-Maildoor: WaflineMail 1.00r
{Jason Haines} said
"what to do with old 256k"
to <All> on 04-15-93  04:38
JH> I was wondering if people had any good uses for old
JH> 256k SIMMs.  I have a bunch of them for the Apple Mac
JH> and I know lots of other people do to.  I have tried to
JH> sell them but have gotten NO interest.
How about collecting them all together (IE everyones) and
selling them as a lot?  The other thing is to give to a
recycler.
JH> So, if you have an inovative use (or want to buy
JH> some SIMMs  8-) ), I would be very interested in hearing
JH> about it.
If they are free and you can send them real cheap!  I would
be intrested in them.  hehehe  Are these 2 chip or 8 chip
devices what speed?
JH> I have seen RAM disc storage devices but they have been
JH> very pricey (plus I am still a little worried about having data
JH> stored on RAM).
Why?  Do you use a RAM disk? :)
Stephen Cyberman@Toz.Buffalo.NY.US
Mangled on Fri  04-16-1993  at 19:58:29
... Badgers... we don't need no steenking Badgers!
___ Blue Wave/QWK v2.12
From: cyberman@toz.buffalo.ny.us (Cyberman)
Subject: Re: what to do with old 2
Lines: 19
X-Maildoor: WaflineMail 1.00r
{Kris Gleason} said
"Re: what to do with old 2"
to <All> on 04-15-93  11:02
KG> Yeah... keychains.  I have seen 64K simms with a silver
KG> keyring attached, big seller at the computer store.  I'm
KG> sure you could find a bunch of geeks^H^H^H^H^H^H computer
KG> science majors around that would buy them for $10.  Maybe
KG> $15, if you're lucky.
Untrue they would check JDR first and say 5.  That's how much
they are worth AT MOST.  My guess is they are worth 1 buck
a peice.
Stephen Cyberman@Toz.Buffalo.NY.US
Mangled on Sat  04-17-1993  at 20:26:37
... This tagline is a duplicate.   This tagline is a duplicate.
___ Blue Wave/QWK v2.12
From: thompson@cactus.org (Charles Thompson)
Subject: How does "Differential Mode" GPS work???
Organization: Capital Area Central Texas UNIX Society, Austin, Tx
Lines: 15
I understand that the new GPS boxes now have an option
known as "differential ready".  Apparently land-based
beacons tranmit GPS correction information to your GPS
receiver (with differential option installed).
How does this system work?  What frequency is used for
the land-based beacons?
Thanks in advance,
Charlie Thompson
.
From: ski@wpi.WPI.EDU (Joseph Mich Krzeszewski)
Subject: Re: Need to find out number to a phone line
Organization: Worcester Polytechnic Institute
Lines: 4
NNTP-Posting-Host: wpi.wpi.edu
In Texas (Well, Corpus Christi anyway) if you pick up the phone and dial
890 the phone company will read back the number to you.
Try it. It might work.
From: rcook@gfx.engga.uwo.ca (Richard Cook)
Subject: Re: Need to find out number to a phone line
Organization: University of Western Ontario, London
Nntp-Posting-Host: server.gfx.engga.uwo.ca
Lines: 23
In article <20756.2bd16dea@ecs.umass.edu> alee@ecs.umass.edu writes:
>
>Greetings!
>
>        Situation:  I have a phone jack mounted on a wall.  I don't
>                    know the number of the line.  And I don't want
>                    to call up the operator to place a trace on it.
>
>        Question:   Is there a certain device out there that I can
>                    use to find out the number to the line?
>        Thanks for any response.
>                                                    Al
>
>
How about calling someone with the Caller ID service and have them call you back
with the number?
--
Richard Cook    (519) 641-1985     E-mail:  rcook@gfx.engga.uwo.ca
Elect. Eng. FAX	(519) 661-3488
From: markz@ssc.com (Mark Zenier)
Subject: Re: Can I use a CD4052 analog multiplexer for digital signals?
Organization: SSC, Inc.,  Seattle, WA
X-Newsreader: TIN [version 1.1 PL6]
Lines: 13
Tall Cool One (rky57514@uxa.cso.uiuc.edu) wrote:
: As the subject says - Can I use a 4052 for digital signals?  I don't see
: why it couldn't handle digital signals, but I could be wrong.  Anyone have
: any advice?  Thanks.
The switches have a non-negligable on resistance (up to 1k ohm when
powered by 5 volts) and a maximum current and a Maximum Static
Voltage Across Switch.  Not a good bet for TTL.  Should work for
CMOS, but slow things down a bit.  There are 74HC versions that
have better specs. but lower max voltage.
Mark Zenier  markz@ssc.wa.com  markz@ssc.com
From: markz@ssc.com (Mark Zenier)
Subject: Re: Illusion
Organization: SSC, Inc.,  Seattle, WA
X-Newsreader: TIN [version 1.1 PL6]
Lines: 22
Chris Best (cab@col.hp.com) wrote:
: > This is not a new idea.  At least 10 years ago I got this little gadget with
: > a keyboard on the back and 8 LED's in a vertical row on the front.  It has a
: > long handle and when you wave it in the air it "writes" the message you typed
: > on the keyboard in the air.
:
: This is not news.  In fact it's where I got the idea from, since it was
: such a neat item.  Mattell made it, I believe, modeled after a "space
: saber" or "light sword" or something likewise theme-y.  My addition was
: using a motor for continuous display, and polar effects in addition to
: character graphics.  I should have protected it when I had the chance.
: No one to kick but myself...
:
: Ten years ago is about right, since I built mine in '84 or '85.
It's even older than that.  I remember seeing a description of
a garage operation selling them at some of the early Computer Faires
in San Francisco about 5 years before that.
Mark Zenier  markz@ssc.wa.com  markz@ssc.com
From: dnewman@lynx.dac.northeastern.edu (David F. Newman)
Subject: voltage regulator spec needed !!!!!
Organization: Division of Academic Computing, Northeastern University, Boston, MA. 02115 USA
Lines: 13
Hi there,
I have a mac 512 with a burned out part which looks like a voltage
regulator.  The part number is BU 406 and I believe the vender is
SGS thomas judging by teh SGS logo printed on the package.  If anyone
has teh spec for this part I would greatly appreciate an email with
the import info so I can find a replacement.  Thanx in advance.
-Dave
dnewman@lynx.northeastern.edu
BTW I don't need people telling me to throw the computer away.  If
I had the money the thing would be in the trash in a second, but
it does make a good terminal if nothing else.
From: berryh@huey.udel.edu (John Berryhill, Ph.D.)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Nntp-Posting-Host: huey.udel.edu
Organization: little scraps of paper, mostly
Lines: 13
The object of a cooling tower is to distribute dissolved salts in
cooling water over large areas of farmland and to therefore decrease
farm subsidies for non-producers by rendering their land infertile.
A side effect of this deficit-reduction program is that they provide
a low-T reservoir for a variety of industrial processes.
Now you know.
--
John Berryhill
From: xandor@unixg.ubc.ca (John Gilbert )
Subject: Re: Exploding TV!
Organization: The University of British Columbia
Lines: 4
Distribution: usa
NNTP-Posting-Host: unixg.ubc.ca
Just as a not of possible interest on this subject ..
It is my understanding that exploding televisions were a major cause of
domestic accidents in the Soviet Union in past years!
From: jeh@cmkrnl.com
Subject: Re: A question about 120VAC outlet wiring.
Distribution: world
Organization: Kernel Mode Systems, San Diego, CA
Lines: 35
In article <1qmisf$odp@sdl.Warren.MENTORG.COM>, garyg@warren.mentorg.com (Gary Gendel) writes:
> In article 1834@cmkrnl.com, jeh@cmkrnl.com writes:
>>What you CAN do if you want three-prong outlets without additional wiring is
>>to use a GFCI outlet (or breaker, but the outlet will be cheaper).  In fact,
>>depending on where you are putting your new outlet(s), a GFCI may be *required*.
>
> You still need to supply a proper ground for a Ground Fault Circuit Interrupter!
Not according to the NEC nor the CEC, as explained in the electrical wiring
FAQ, which I posted here separately.  Note the material under the headings
> Subject: How do I convert two prong receptacles to three prong?
and
> Subject: Are you sure about GFCIs and ungrounded outlets?
> 	Should the test button work?
Of course, as they said -- "Local codes may vary".
> So rewiring is still a part of this job, however, the ground may be connected to
> a local earth ground, rather than back at the breaker box.
I'm not sure about this.  If the ground connections on the outlets are
connected to anything, they should be connected to a wire that runs back to the
main panel, where it is bonded to the neutral connector and to the house ground
rod.  A connection to a local earth ground would not necessarily meet one of
the goals of the ground wire, which is that if a short develops from hot
to the ground wire, enough current would flow to trip the breaker.
Hmmm.  How are those orange "isolated ground" outlets (often used in
computer rooms) wired?
--- Jamie Hanrahan, Kernel Mode Systems, San Diego CA
Internet:  jeh@cmkrnl.com  Uucp: uunet!cmkrnl!jeh  CIS: 74140,2055
From: sgberg@charon.bloomington.in.us (Stefan G. Berg)
Subject: Re: Motorola XC68882RC33 and RC50
Reply-To: sgberg@charon.bloomington.in.us (Stefan Berg)
Distribution: world
Organization: Not an Organization
X-NewsSoftware: GRn 1.16f (10.17.92) by Mike Schwartz & Michael B. Smith
Lines: 25
In article <16APR199323531467@rosie.uh.edu> st1my@rosie.uh.edu (Stich, Christian E.) writes:
> I just installed a Motorola XC68882RC50 FPU in an Amiga A2630 board (25 MHz
> 68030 + 68882 with capability to clock the FPU separately).  Previously
> a MC68882RC25 was installed and everything was working perfectly.  Now the
> systems displays a yellow screen (indicating a exception) when it check for
> the presence/type of FPU.  When I reinstall an MC68882RC25 the system works
> fine, but with the XC68882 even at 25 MHz it does not work.  The designer
> of the board mentioned that putting a pullup resistor on data_strobe (470 Ohm)
> might help, but that didn't change anything.  Does anybody have some
> suggestions what I could do?  Does this look like a CPU-FPU communications
> problem or is the particular chip dead (it is a pull, not new)?
> Moreover, the place I bought it from is sending me an XC68882RC33.  I thought
> that the 68882RC33 were labeled MC not XC (for not finalized mask design).
> Are there any MC68882RC33?
I, too, have a XC68882RC50 math coprocessor, which I installed
succesfully in my Mega Midget Racer (clocked at 33 MHz). I have tried
clocking my FPU at 28 to 50 MHz and it all worked just fine. I have a
MC68030-33 CPU. I don't know why my FPU has an XC (my original 33MHz FPU
was label MC68882-33), but it seems to work fine on my system. Maybe you
just have a bad chip.
Stefan
P.S. Or does it mean eXperimental Chip instead of Motorola Chip? .-)
From: mniederb@pws2.itr.ch (Niederberger Markus)
Subject: Characterization of opamps
Organization: Interkantonales Technikum Rapperswil (ITR) Switzerland
Lines: 23
Hi,
Right now I should do some characterization of opamps. Because I don't
have
special equipment for this task, I have to do this job with relativly
simple
equipments (Frequency sweeper, DSO, etc.).
Does anyone know good test circuitry for characterization of opamps?
Especially for measuring open-loop gain, phase margin, PSSR, CMMR and so
on.
Are there any books or application notes on this subject available?
Please reply vi e-mail or nn.
Thanks
Mark
__________________________________________________________________________
_____
Mark Niederberger
E-mail: mniederb@itr.ch
__________________________________________________________________________
_____
From: hjkim@hyowon.pusan.ac.kr (Hojoong Kim)
Subject: Looking for Electronics Dept Info in Austrailia
Organization: Korea Advanced Institute of Science and Technology
X-Newsreader: TIN [version 1.1 PL8]
Lines:       13
Hi Netters!
I am looking for the list of universities in Austrailia, which has electronics department.
I am considering to spend a year for research in Austrailia about communication area.�� I am interested in Mobile communication areas and spread spectrum communications etc.
But I don't have any information about Austrailian Universities.
Can anybody recommend a good university in co��mmunic��ation area?
Any comments will be welcomed!
Bye.
Jaehyung Kim
From: jgd@dixie.com (John De Armond)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: Dixie Communications Public Access.  The Mouth of the South.
Lines: 99
nagle@netcom.com (John Nagle) writes:
>>Great Explaination, however you left off one detail, why do you always
>>see them at nuclear plants, but not always at fossil fuel plants.  At
>>nuclear plants it is prefered to run the water closed cycle, whereas
>>fossil fuel plants can in some cases get away with dumping the hot
>>water.  As I recall the water isn't as hot (thermodynamically) in many
>>fossil fuel plants, and of course there is less danger of radioactive
>>contamination.
Actually the reasons you don't see so many cooling towers at fossil plants are
1) fossil units (multiple units per plant) are generally smaller than
nuclear plants.  300 MWe seemed to be a very popular size when many
fossil plants were built.  The average nuclear plant is 1000 MWe.  2) many
fossil plants were grandfathered when water discharge regulations were
adopted ("why those old dirt burners can't harm anything, let 'em go.").
3) powered draft cooling towers, low enough to the ground to be generally
not visible from off-site, are quite popular with fossil plants.  4) fossil
plants used to get much less regulatory attention than nuclears.
>       Actually, fossil fuel plants run hotter than the usual
>boiling-water reactor nuclear plants.  (There's a gripe in the industry
>that nuclear power uses 1900 vintage steam technology).  So it's
>more important in nuclear plants to get the cold end of the system
>as cold as possible.  Hence big cooling towers.
>       Oil and gas fired steam plants also have condensers, but they
>usually are sized to get the steam back into hot water, not most of the
>way down to ambient.  Some plants do cool the condensers with water,
>rather than air; as one Canadian official, asked about "thermal
>pollution" de-icing a river, said, "Up here, we view heat as a resource".
Actually the condensing environment is essentially the same for plants
of similar size.  The issues are the same regardless of where the
heat comes from.  Condensers are run at as high a vacuum as possible in
order to reduce aerodynamic drag on the turbine.  The condenser pressure is
normally water's vapor pressure at the condensing temperature.  It is
desirable that the steam exhaust be free of water droplets because
moisture in the steam causes severe erosion damage to the turbine
low pressure blades and because entrained water moving at high velocity
causes erosion of the condenser tubes.  The coldest and thus lowest
pressure condensing environment is always the best.
A related issue is that of pumping the condensate from the hotwell (where
the water ends up after dripping off the condenser tubes.)  Since the
condenser is at a very low pressure, the only force driving the
condensate into the hotwell pumps is gravity.  If the condensate is too
hot or the gravity head is too low, the condensate will reflash into
steam bubbles and cause the condensate pumps to cavitate.  This is a
particularly destructive form of cavitation that is to be avoided at all
costs.
The hotwell pumps are located in the lowest point in the plant
in order to provide a gravity head to the pumps.  How much lower
they must be is a function of how hot the water is allowed to get in
the hotwell.  Typically hotwell temperatures run between 100 and 120
degrees depending on the temperature of the river water (this term is
used to describe the river grade water even when the cooling tower
system is operating in closed loop mode and essentially no river water
is pumped.)  When the river water temperature is high in the summer,
operators will typically allow the hotwell level to rise in order
to provide more gravity head.  There is a tradeoff involved since higher
hotwell levels will encroach onto the condensing tubes and reduce the
condenser area.
At least in the East and elsewhere where moisture actually exists in the
air :-), the river water will almost always be cooler than the discharge
water from the cooling towers.  The temperature of the discharge water
from the cooling towers is set by the ambient air temperature and
humidity.  It is very rare in the East to hear of actual river water
temperatures exceeding 70 degrees.  A vast difference from the typical
"95-95" days (95 degrees, 95% humidity) we see routinely in the East.
It is not unusual, particularly where the econazis have been successful
in clamping rigid discharge water temperature limits on a plant, for the
plant to have to reduce the firing rate when the air temperature gets
too high and the condenser cannot handle the heat load without excessive
pressure.
>       Everybody runs closed-cycle boilers.  The water used is
>purified of solids, which otherwise crud up the boiler plumbing when
>the water boils.  Purifying water for boiler use is a bigger job than
>cooling it, so the boiler water is recycled.
True.  Actually secondary plant (the part that makes electricity and
feeds feedwater to the boiler) water chemistry has been the bastard
stepchild until recently and has not gotten the respect it deserves.
The plant chemists have just in the past decade or so fully understood
the costs of impure water.  By "impure", I mean water with a few
dozen extra micromho of conductivity and/or a few PPM of dissolved
oxygen.  Secondary water is now typically the most pure one will
find outside the laboratory.
John
--
John De Armond, WD4OQC               |Interested in high performance mobility?
Performance Engineering Magazine(TM) | Interested in high tech and computers?
Marietta, Ga                         | Send ur snail-mail address to
jgd@dixie.com                        | perform@dixie.com for a free sample mag
Lee Harvey Oswald: Where are ya when we need ya?
From: marrevola@rediris.es
Subject: Re: What is Zero dB????
Organization: REDIRIS, Red Nacional de I+D
Lines: 24
In article <1993Apr6.132429.16154@bnr.ca>, moffatt@bnr.ca (John Thomson) writes:
> Joseph Chiu (josephc@cco.caltech.edu) wrote:
>
> : And the measure of current, Amp, is actually named after both the AMP company
> : and the Amphenol company.  Both companies revolutionized electronics by
> : simulatenously realizing that the performance of connectors and sockets
> : were affected by the amount of current running through the wires.
>
> Sorry.  The unit for current is the AMPERE which is the name of a french-man
> named AMPERE who studied electrical current.  The term AMP is just an abbreviation
> of it.  The company AMP came after the AMPERE unit was already in use.
>
> : The Ohmite company was the first to characterize resistances by numbers, thus
> : our use of the Ohms...
>
> I don't know about this one, but it doesn't sound right.
Are you (two) joking?
Is the entire Internet flaming you (two)?
Ahh!, now I remember that Ohmite company was the first introducing "the pink
colored resistor", only for electronics working females ;-)
--
Manuel Arrevola Velasco   ||||| True e-mail: manolo@taf.fundesco.es |||||
DoD #1033
From: webb@itu1 (90-29265  Webber  AH)
Subject: Re: Adcom cheap products?
Organization: Rhodes University, Grahamstown, South Africa
X-Newsreader: TIN [version 1.1 PL8]
Lines: 52
Aaron Lung (alung@megatest.com) wrote:
: >I was also sceptical about the amps being built in the far-east
: >  or where-ever.  But if you look in the amp and see what components
: >  they use and how it was designed, you can easily see why the
: >  amplifiers sound so brilliant.
: Good point...also, I wouldn't be surprised that the components
: they use off-shore are of inferior quality.  As long as it was
: properly designed and robust, premium components are used, it
: shouldn't matter where it is assembled.
Definately, I agree wholeheartedly.  If they can build the amp where
the labour is not so expensive, they can afford to put decent
components in and go to more effort to improve the design of the
amplifier - as Adcom has done.
: >I cannot see why people say the amplifier won't last - not with
: >  those quality components inside.  Sure the amp runs very fairly
: >  hot - but that's how you get an amp to sound incredibly good.
: An amp that runs hot has no bearing on how it's gonna sound.
: The amp you have probably is running Class-A the whole day.
: Actually, I'd be wary of excessively hot amps, 'cauz even though
: the components inside may be rated to run that way, excessive
: heat will dramatically shorten the life of *any* electronic component
: regardless of quality.  In fact, an amp that does run hot to the touch is
: because either the engineer or manufacturer of that amp wanted
: to skimp on heatsinking or cooling to save costs!  Hmmmmm....
Sure, I didn't mean to imply that because of the heat generated, the
amp sounds good.  My Adcom GFP 535II runs fairly warm - not hot to
the touch - but enough to satisfy me that the amp is running nicely.
I don't like it when an amp runs dead-cold.  It makes one think that
the amp is doing nothing :)
The heatsinks that Adcom uses in their amps are certainly far for
skimpy - they're massive things with heating vents both below
and above.  More than enough to carry away excessive heat.
My opinions once again.
--
***********************************************************************
**    Alan Webber                                                    **
**                      webb@itu1.sun.ac.za                          **
**                      webb@itu2.sun.ac.za                          **
**                                                                   **
** The path you tread is narrow and the drop is sheer and very high  **
** The ravens all are watching from a vantage point near by          **
** Apprehension creeping like a choo-train up your spine             **
** Will the tightrope reach the end; will the final couplet rhyme    **
***********************************************************************
From: jhwhit01@ulkyvx.louisville.edu
Subject: Re: What's a good IC for RS232 -> TTL signals??
Lines: 18
Nntp-Posting-Host: ulkyvx.louisville.edu
Organization: University of Louisville
In article <C5nz60.99z@scraps.uucp>, frankh@scraps.uucp (Frank Holden KA3UWW) writes:
> In <C57zsC.9FL@news.cso.uiuc.edu> rky57514@uxa.cso.uiuc.edu (Tall Cool One ) writes:
>
>>I'm looking for an IC that will convert RS232 voltage levels to TTL voltage
>>levels.  Something relatively inexpensive would be nice, too.  Anyone have
>>a suggestion??  Thanks.
>
> Well it looks as if Digi-Key sells a chip with the number ICL232 that does what
> you want.  They are selling it for about $3.50...
Digi-Key also sells Quad Line Receivers, parts DS1489AN (68cents) and DS1489N
(48cents).  A Quad Line Driver, part DS1488 (48cents), is also sold.  I guess
if you don't won't to supply +12V, the chips with the pump-up circuitry might
be worth the extra cost.  But 1488's and 1489's are available at your friendly
neighborhood RS, parts MC1488 (276-2520) for $1.29 and MC1489 (276-2521) for
$1.29.
Jeff White          jhwhit01@ulkyvx.louisville.edu
From: conrad@spva.ph.ic.ac.uk (Conrad Winchester)
Subject: Re: Motorola XC68882RC33 and RC50
Keywords: Motorola, FPU, 68882, 68030, 33/50 MHz, problems (FPU exception)
Nntp-Posting-Host: prawn.sp.ph
Organization: Imperial College of Science, Technology, and Medicine, London, England
Lines: 25
In article <16APR199323531467@rosie.uh.edu>, st1my@rosie.uh.edu (Stich, Christian E.) writes:
-| I just installed a Motorola XC68882RC50 FPU in an Amiga A2630 board (25 MHz
-| 68030 + 68882 with capability to clock the FPU separately).  Previously
-| a MC68882RC25 was installed and everything was working perfectly.  Now the
-| systems displays a yellow screen (indicating a exception) when it check for
-| the presence/type of FPU.  When I reinstall an MC68882RC25 the system works
-| fine, but with the XC68882 even at 25 MHz it does not work.  The designer
-| of the board mentioned that putting a pullup resistor on data_strobe (470 Ohm)
-| might help, but that didn't change anything.  Does anybody have some
-| suggestions what I could do?  Does this look like a CPU-FPU communications
-| problem or is the particular chip dead (it is a pull, not new)?
-| Moreover, the place I bought it from is sending me an XC68882RC33.  I thought
-| that the 68882RC33 were labeled MC not XC (for not finalized mask design).
-| Are there any MC68882RC33?
-|
-| Thanks
-| 	Christian
-|
Have you changed the crystal that clocks for the FPU. If you
haven't then it won't work.
Conrad
From: agodwin@acorn.co.uk (Adrian Godwin)
Subject: Re: Single chip receiver for FSK?
Organization: Acorn Computers Ltd, Cambridge, UK
Lines: 26
In article <C5L0xM.E25@law7.DaytonOH.NCR.COM> jra@law7.DaytonOH.NCR.COM (John Ackermann x 2966) writes:
>My goal is to come up with an inexpensive design for a receiver "back
>end" with IF input on one end and an FSK demondulator on the other.  I'm
>particularly interested in ways to use a higher IF than 10.7 -- do any
>current chips work up to, say 150MHz with internal downconversion so a
>normal IF filter can be used?
>
GEC/Plessey specify a series of FM demodulators (SL1454 etc) for use in
satellite TV receivers : 150 or 600MHz in, 10MHz of baseband video out.
I think there's also a related data slicer / clock recovery circuit intended
for use in DMAC decoders, though that isn't used in the most common
implementation - it may not be in volume production.
The most easily available components probably vary with local satellite
standards, and I think the european systems vary rather widely from those
in the US - so it may be worth investigating locally-available receiver
designs to find out what's in common use.
-adrian
--
Adrian Godwin : agodwin@acorn.co.uk : adrian@fangorn.demon.co.uk : g7hwn@gb7khw
ObDisclaimer  : I believe this rubbish .. don't imagine that anyone else does.
From: andrei@labomath.univ-orleans.fr (Andrei Yakovlev)
Subject: References to switched-capacitor filter ICs wanted.
Organization: University of Orleans, France.
Lines: 9
Hi All!
I would like to know what are the popular ICs of the type, their capabilities
(# of channels et.c.) and prices :-)
Great thanks,
Andrew.
From: bills@inqmind.bison.mb.ca (Bill Shymanski)
Subject: Re: Dmm Advice Needed
Organization: The Inquiring Mind BBS  1 204 488-1607
Lines: 41
kolstad@cae.wisc.edu (Joel Kolstad) writes:
> In article <734953838.AA00510@insane.apana.org.au> peter.m@insane.apana.org.a
> >
> >If you are going to use one where it counts (eg:aviation, space scuttle,
> >etc) then I suggest you go and buy a Fluke (never seen a Beckman), however
> >for every other use you can buy a cheapie.
>
> My Beckman died a few days ago, thanks do about a 4 or 5 foot drop onto a
> lab table.  !@#!@$#!@$@#$  Probably not indicative of anything, but I've
> already filled out the requisition for a Fluke 87. :-)
>
> Oh yeah, and sometimes our measurements here do count.  Not often, but often
> enough that I want at least _one_ good meter!
> 					---Joel Kolstad
We used to buy Beckman 110 and HD110 ("ruggedized") versions for use
by electricians in the steel mill where I work.   After a while we
got round to filling all the current-input jacks with silicone -
electricians have a regrettable habit of not checking where the last
guy left the leads before using a 3 1/2 digit 0.5 % autoranging $400
meter to check if a fuse is good or not. Its very hard on meters
(and electricians) when you put the milliamp shunt across a 600 volt
bus.
But that's not why we stopped buying Beckmans - after a while a
lot of them got "funny" in the LCD display.  A black stain would
spread from one edge, or else they'd come adrift from those
Zebra connectors and fail to operate.    Now we buy Flukes, the
low-end 20 series mostly ( and we still fill the amp jack with
silicone).
What the world needs is a meter that won't let you change ranges or
turn it on/off with a lead stuck in the amps jack - a little bit of
clever plastic detailing would take care of this and make the world
safer for electricans, anyway.
Not that I've ever put a meter on the wrong range into a live
circuit, no, not me...not more than a dozen times, anyway....
Bill
bills@inqmind.bison.mb.ca
The Inquiring Mind BBS, Winnipeg, Manitoba  204 488-1607
From: mdgoodma@apgea.army.mil (Malcolm D. Goodman <mdgoodma>)
Subject: Sale -- Fiber Optic Modems, RF Modem, etc -- Best Offer
Distribution: na
Organization: APG-Edgewood, MD, USA
Lines: 26
PLease take these and use them.  Take advantage of me... I really
don't know what they are worth.
Qty 2  -  Canoga Perkins Fiber Optic Modems, Model 2250, RS-422
Interface, appear new.  I have powered up but that's all,
I have not used them and I cannot tell you whether they
work or not.
Make Offer.........
Qty 1 -   ISC Datacom RF Modem, Model 1056-TX1-RX5-SM-120, Interface
RS-449, Internal Fan, powers up fine but otherwise condition
unknown, Phone # for the company is 408-747-0300.
Make Offer ............
Qty 1 -   Motorola UDS  212 A/D  Modem, RS-232 interface appears to work
but I have not and cannot check it.
Make Offer  .............
Thanks and please buy this stuff or it goes out the door
Mack
mdgoodma@cbda8.apgea.army.mil
.
From: krouth@slee01.srl.ford.com (Kevin Routh)
Subject: F.Y.I.: ImageWriter to Windows...
Organization: Ford Motor Company Research Laboratory
Lines: 53
NNTP-Posting-Host: slee01.srl.ford.com
X-Newsreader: Tin 1.1 PL5
[ Article crossposted from comp.windows.ms ]
[ Author was Kevin Routh ]
[ Posted on 19 Apr 1993 12:35:55 GMT ]
For your information:
I hooked up my ImageWriter I to my COM1 serial port and used the C-Itoh
8510 driver in Windows 3.1.  The cable I am using is a straight-thru
cable connected to a Null Modem Adapter I got at Radio Shack (catalog
#26-1496a) for $4.95.  It seems to work fine with both DOS and Windows.
I used the following command in DOS
C:\DOS\mode COM1:9600,n,8,1,p
and set up the port the same way in the Windows Ports setup.
the Null Modem connections are as follows:
1	to	1
2	to	3
3	to	2
4	to	5
5	to	4
6+8	to	20
20	to	6+8
7	to	7
I printed from several applications and all seems OK.
--
Kevin C. Routh                     Internet:    krouth@slee01.srl.ford.com
Ford Electronics                   IBMmail (PROFS):               USFMCTMF
ELD IC Engineering
17000 Rotunda Drive, B-121         Voice mail:              (313) 337-5136
Dearborn, MI  48121-6010           Facsimile:               (313) 248-6244
--
Kevin C. Routh                     Internet:    krouth@slee01.srl.ford.com
Ford Electronics                   IBMmail (PROFS):               USFMCTMF
ELD IC Engineering
17000 Rotunda Drive, B-121         Voice mail:              (313) 337-5136
Dearborn, MI  48121-6010           Facsimile:               (313) 248-6244
--
Kevin C. Routh                     Internet:    krouth@slee01.srl.ford.com
Ford Electronics                   IBMmail (PROFS):               USFMCTMF
ELD IC Engineering
17000 Rotunda Drive, B-121         Voice mail:              (313) 337-5136
Dearborn, MI  48121-6010           Facsimile:               (313) 248-6244
From: sean@dip1.ee.uct.ac.za (Sean Borman)
Subject: INFO WANTED : Graphics LCD displays
Organization: University of Cape Town
X-Newsreader: TIN [version 1.1 PL8]
Lines: 15
Hi there
Does anyone know how to get hold of data as well as stock of the
LCD displays used in the NINTENDO GAMEBOY handheld TV game machines?
Any information wouold be MOST appreciated.
Please e-mail any replies to
arawstorne@eleceng.uct.ac.za
thanks
Alex
Subject: PACE MODEM
From: mora@verdi.cineca.it (Stefano Mora)
Distribution: world
Nntp-Posting-Host: verdi.eng.unipr.it
Lines: 19
Hi,
I've got a PACE MODEM , Series Four 2400s ( made in England by
PACE Micro Technology ) with a broken power supply .
So I'd like to know :
- the voltage and current values of the original
power supply PS1001.
- the pinout of the power supply connector.
- the pinout of the USER PORT and how to use it.
Many thanks in advance to all the people help me.
Please post the reply also to my e-mail..........
+--------------------------------------------------+
|                                                  |
|  Sender: Stefano Mora                            |
|  eMail : mora@verdi.eng.unipr.it                 |
|                                                  |
+--------------------------------------------------+
From: gould@waterloo.hp.com (Dan Gould)
Subject: Telephone Controlled Power Bar Needed
Nntp-Posting-Host: hppadan.waterloo.hp.com
Organization: HP Panacom Div Waterloo ON Canada
X-Newsreader: TIN [version 1.1 PL8.9]
Lines: 16
I would appreciate some help in locating a telephone controlled power bar
for my PC. The unit would power up the PC when the telephone rings and
keep it up as long as the telephone connection is present.
I also need to be able to power up this same PC through the use of an external
timer. I can supply power or a contact closure to do this.
I will summarize and post the results of this query here.
Thank you.
--
Dan Gould
gould@waterloo.hp.com
From: kehoe@netcom.com (Thomas David Kehoe)
Subject: Re: How starters work really
Keywords: fluorescent bulb starter neon
Organization: Netcom - Online Communication Services (408 241-9760 guest)
Lines: 35
>>So when you turn on the power, this causes the bulb to work like a neon,
>
>Imprecise. This description
>
> 1. ignores the role of the ballast,
> 2. misrepresents the heating effects in the starter.
>
>The bimetalic strip cools down immediately after the contacts
I've been thinking of sending into Mad magazine an idea for a
parody, of those books entitled "How Things Work" that
engineers buy their sons, which explain how engines, elevators,
flourescent lights, etc. work.
The parody would be "How Things Really Work."  Under "Canned
Food", on the left page you'd see the description from
"How Things Work": gleaming stainless steel equipment
pasteurizing the food to precisely the right temperature,
then sealing the can in an oxygen-free environment, etc.
On the right page you'd see "How Things Really Work":
brain-dead workers sending disgusting food to the
gleaming equipment -- rotting vegetables, parts of
animals people don't eat, barrels of sugar and chemicals.
Under "Elevators" you'd see (on the left) computer geniuses
working out algorithms so that X number of people
waiting for Y elevators will get to Z floors in the shortest
time.  On the right, you'd see giggling elevator controllers
behind a one-way mirror in the lobby choosing which people
appear to be in the biggest hurry and making them wait longest.
--
"Why my thoughts are my own, when they are in, but when they are out
they are another's." - Susannah Martin, hanged for witchcraft, 1692.
Thomas David Kehoe          kehoe@netcom.com         (408) 354-5926
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Subject: Re: History question
Organization: NASA Langley Research Center and Reptile Farm
Lines: 16
NNTP-Posting-Host: grissom.larc.nasa.gov
In article <2775@snap> paj@uk.co.gec-mrc (Paul Johnson) writes:
>
>I recall reading of a phonograph which used mechanical amplification.
>Compressed air was squirted out of a valve which was controlled by the
>pickup.  The result was noisy and distinctly lo-fi, but much louder
>than a conventional phonograph.  It tended to wear the disks out
>pretty quickly though.
This was the Pathe you are thinking of, although there were other imitators.
It didn't wear the disks any more than conventional acoustic designs, but
it did have a high noise level due to the continual hiss of escaping air.
There are a lot of them still operating, and they are pretty ingenious.
There was a pneumatic amplifier designed by Alexander Graham Bell, as well,
but I don't know if it was ever constructed.
--scott
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Subject: Re: Need to find out number to a phone line
Organization: NASA Langley Research Center and Reptile Farm
Lines: 16
NNTP-Posting-Host: grissom.larc.nasa.gov
In article <20756.2bd16dea@ecs.umass.edu> alee@ecs.umass.edu writes:
>
>Greetings!
>
>        Situation:  I have a phone jack mounted on a wall.  I don't
>                    know the number of the line.  And I don't want
>                    to call up the operator to place a trace on it.
>
>        Question:   Is there a certain device out there that I can
>                    use to find out the number to the line?
Call a friend long distance, collect.  Ask to speak with yourself.  When
the operator asks for you, you won't be there, so ask the operator to leave
your number.  She'll read it out in the clear.
--scott
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Subject: Re: subliminal message flashing on TV
Organization: NASA Langley Research Center and Reptile Farm
Lines: 19
NNTP-Posting-Host: grissom.larc.nasa.gov
In article <7480237@hpfcso.FC.HP.COM> myers@hpfcso.FC.HP.COM (Bob Myers) writes:
>> Hi.  I was doing research on subliminal suggestion for a psychology
>> paper, and I read that one researcher flashed hidden messages on the
>> TV screen at 1/200ths of a second.  Is that possible?  I thought the
>> maximum rate the TV was even capable of displaying images was 1/30th
>> of a second.  (or 1/60th of a second for an image composed of only odd
>> or even scan lines)
>
>You are correct; the fastest "complete" image that could be presented on
>TV would be one field, which is 1/60 of a second (approximately).  Of course,
>the phrase "TV screen" is often thrown around in reference to any CRT
>display, so perhaps this researcher wasn't using normal TV rates.  Might
>even be a vector ("strokewriter") display, in which case the lower limit
>on image time is anyone's guess (and is probably phosphor-persistence limited).
Actually, a lot of this work used to be done with a CRT that had a beamsplitter
mounted in front, and a tachistoscope driving it.  The tachistoscope is really
just a slide projector with a very fast shutter.  Low tech, but it does the job.
--scott
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Subject: Mysterious MOSFET
Organization: NASA Langley Research Center and Reptile Farm
Lines: 9
Distribution: world
NNTP-Posting-Host: grissom.larc.nasa.gov
I have a MOSFET pulled out of a Trygon power supply, for which I have no
manual.  It's a Motorola part with a 1972 date code and the number
285-4
which the Motorola folks assure me is a house number, which they can't
help me with.  Any suggestions from folks out there?  I can't put it on
a curve tracer to try to get an equivalent, since it's completely shot.
--scott
From: bakerjp1@netnews.jhuapl.edu (Baker John P. PDD x4895 )
Subject: How does "Differential Mode" GPS work???
Summary: Explaination of DGPS system
Keywords: GPS, differential, navigation, radio
Organization: JHU/Applied Physics Laboratory
Lines: 46
>I understand that the new GPS boxes now have an option
>known as "differential ready".  Apparently land-based
>beacons tranmit GPS correction information to your GPS
>receiver (with differential option installed).
>How does this system work?  What frequency is used for
>the land-based beacons?
>Thanks in advance,
>Charlie Thompson
>.
Here's a rough sketch of how the system works.  A reference station
with a very exactly known position computes the errors in the
incoming GPS signals.  These errors are due to several factors
including atmospheric distortion, SA (Selective Availability) time
dithering, etc.  The reference unit contains complex computational
equipment to "back out" the errors in its position (since it knows
where it is already).  It then transmits these corrections on a
broadcast which is available to any number of relatively local
receivers.  If the receivers are nearby (<300km) and are using
the same satellites as the reference unit, the errors should be very
similar for the reference unit and the receiver unit.  Thus, the
receiver unit may apply the corrections calculated by the reference
unit.
The US Coast Guard is currently (as far as I know) installing a series
of coastline transmitters for differential GPS.  These stations will
use existing radio towers.  I believe the frequency is to be approximately
305 kHz.  There are many other private corporations offering DGPS signals
on different frequencies.  For example, PinPoint ((310)-618-7076) offers
correction signals and receiver units using an FM broadcast system
which has stations all across the US.
The correction codes are usually transmitted using the RTCM 104 format.
Advertised accuracies espouse 1 to 5 meter errors.
-------------------------------------------------------------------------
John P. Baker                   | My opinions are my own.  I don't know
Johns Hopkins University        | anyone else who wants them, anyway.
Applied Physics Laboratory	|
Laurel, MD  20723               | bakerjp1@aplcomm.jhuapl.edu
--------------------------------------------------------------------------
From: mjhill@eos.ncsu.edu (MICHAEL JAMES HILL)
Subject: New applications of electronics
Originator: mjhill@c00483-224wi.eos.ncsu.edu
Reply-To: mjhill@eos.ncsu.edu (MICHAEL JAMES HILL)
Organization: North Carolina State University, Project Eos
Lines: 8
I'm looking for brief information on new
applications of electronics (or new electronics in
applications.) If you know of any interesting new
stuff, I would be intrested in hearing about it.
Thanks, MJH
From: domain@cbnewsf.cb.att.com (george.d.hodge)
Subject: Dayton Hamfest
Summary: Where and when is Dayton Hamfest
Organization: AT&T
Distribution: usa
Lines: 14
Some weeks ago, someone posted an article telling when and where
a hamfest and computerfest was going to be help in Dayton, OH.
Unfortunately, I lost the article and I was wondering if someone
could repost it.
I believe it was being held the 23,24,and 25 of this month at
the Dayton convention center but I'm not sure.
Any help and more details would be greatly appreciated.
george.d.hodge
domain@cbcat.att.com
From: babb@sciences.sdsu.edu (J. Babb)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Organization: SDSU - LARC
Lines: 8
Distribution: world
NNTP-Posting-Host: larc.sdsu.edu
> I really don't know where to post this question so I figured that
> this board would be most appropriate.
try sci.energy
Jeff Babb
babb@sciences.sdsu.edu   babb@ucssun1.sdsu.edu
Programmer, SDSU - LARC
From: Mike Diack <mike-d@staff.tc.umn.edu>
Subject: 16 bit serial converters
X-Xxdate: Tue, 20 Apr 93 06:56:45 GMT
Nntp-Posting-Host: dialup-slip-1-34.gw.umn.edu
Organization: persian cat & carpet co.
X-Useragent: Nuntius v1.1.1d7
Lines: 2
Someone was looking for these a few weeks ago - check out comp.dsp
Mike.
From: babb@sciences.sdsu.edu (J. Babb)
Subject: Re: Getting rid of screen wiggles?
Organization: SDSU - LARC
Lines: 42
Distribution: world
NNTP-Posting-Host: larc.sdsu.edu
In article <1qpj5t$itg@vela.acs.oakland.edu>, eabyrnes@vela.acs.oakland.edu
(Ed Byrnes) wrote:
>
> My monitor display has a bad case of the wigglies. I have a good ground. I
> live in an old house and I have replaced much of the wiring. I have two
> EMI filters on the computer, the monitor plugs into the computer. When
> fluorescent lights are on upstairs, the display jiggles, when motors run
> in the house, the display jiggles, when incandescent lights are on in the
> kitchen the display jiggles.  I could bring a separate line from the
> breaker box, and use it only for the computer, would this do it? EMI
> doesn't only travel the 110 volt line though. Should I shield the back of
> the monitor? Ground a grid or plate?
> Your expertise is appreciated. Thanks very much!  Ed Byrnes
Aaahh... a problem very near and dear to my heart. In our case, other
monitors cause this problem - the deflection coil of other monitors to be
specific. Have also seen a monitor backed up to a fuse panel exhibit this
problem. This sounds like your problem since flourescent lites, motors, etc
several 10s of feet away seem to me to be too far to cause it, but the
juice running to them must pass nearby your monitor. Fusebox on other side
of wall maybe?
We started spec'ing Panasonic CT-1331Y video monitors (3 switchable input
lines(vid & aud) S-VHS on one) <$400. This stopped the wavy interference
effect on the computer monitor next to it.
Now on to your problem. You need what is known as mu shielding (very
common, in fact almost mandatory on electrostatic deflection type
O'scopes).
I talked to a EE prof. He said get a coffee can, cut both ends off, mount
around deflection coil of interfering monitor.
BE CAREFUL TO AVOID ALL HIGH VOLTAGE CIRCUITRY. ESPECIALLY THE THICKER HIGH
VOLTAGE ANODE LEAD USUALLY COLORED RED. IF YOU KILL YOURSELF, DON'T
BLAME/SUE ME!!! USE PLASTIC OR OTHER NON-CONDUCTING STAND-OFFS AND SUCH TO
MOUNT CAN.
Now, I would assume that what is good for keeping mag fields in is also
good at keeping them out, so hopefully this'll work by mounting shield on
monitor being interfered with as well. If not, start shielding those other
sources.
Jeff Babb
babb@sciences.sdsu.edu   babb@ucssun1.sdsu.edu
Programmer, SDSU - LARC
From: schuch@phx.mcd.mot.com (John Schuch)
Subject: Food Dehydrators
Nntp-Posting-Host: bopper2.phx.mcd.mot.com
Organization: Motorola Computer Group, Tempe, Az.
Distribution: usa
Lines: 9
Does anybody out there have one of those food dehydrators I've been seeing
all over late-night TV recently? I was wondering if they use forced air, heat,
or both. If there's heat involved, anybody know what temperature they run at?
My wife would like one and I'm not inclined to pay >$100.00 for a box, a fan
and a heater. Seems to me you should be able to throw a dehydrator together
for just a few bucks. Heck, the technology is only what? 1,000 years old?
John
From: ski@wpi.WPI.EDU (Joseph Mich Krzeszewski)
Subject: Re: Need to find out number to a phone line
Organization: Worcester Polytechnic Institute
Lines: 9
NNTP-Posting-Host: wpi.wpi.edu
Well, this is my second try at posting on this subject. Here goes...
In Texas (Corpus Christi at least) if you pick up the phone and dial
890 the phone company will read the number of the phone you are on
back to you. I believe the service department uses this to make
certain they are repairing the correct lines when they open the BIG
junction boxes. I don't know if it will work but you can give it a
try. Good luck.
From: billq@ms.uky.edu (Billy Quinn)
Subject: Suggestions  on Audio relays ???
Organization: University Of Kentucky, Dept. of Math Sciences
Lines: 22
I built a little project using the radio shack 5vdc relays to switch
audio.  I got pretty bad 'clicks' when the thing switched.  I was doing
most of the common things one is supposed to do when using relays and
nothing seemed to get rid of the clicks.
My question is:
Is there a good relay/relay circuit that I can use for switching
audio, so that there will be *NO* noise of any kind on the audio lines.
I will appreciate any advice or references to advice.  Also, exact part
numbers/company names etc. for the relays will help!
Thanks!
--
*-----------------------------------------------------------------------*
*	Bill Quinn			billq@ms.uky.edu		*
*-----------------------------------------------------------------------*
From: levy@levy.fnal.gov (Mark E. Levy, ext. 8056)
Subject: Re: What do Nuclear Site's Cooling Towers do?
Nntp-Posting-Host: levy.fnal.gov
Organization: Fermilab Computing Division
Lines: 22
In article <1qngqlINNnp8@shelley.u.washington.edu>, whit@carson.u.washington.edu (John Whitmore) writes:
> In article <C5L5x0.KJ7@vcd.hp.com> johne@vcd.hp.com (John Eaton) writes:
>>-s87271077-s.walker-man-50- (swalker@uts.EDU.AU) wrote:
>
>>During the nuclear fission reaction the uranium fuel can get hot enough
>>to melt. When this happens the liquid uranium is pumped to the cooling
>>tower where it is sprayed into the air.
...
>>Contact with the cool outside air
>>will condense the mist and it will fall back to the cooling tower floor.
>>There it is collected by a cleaning crew using shop vacs and is then
>>reformed into pellets for reactor use the next day.
Another April 1 posting.  Ahhh.
================================================================================
[ Mark E. Levy, Fermilab          |                                            ]
[ BitNet:   LEVY@FNAL             | Unix is to computing                       ]
[ Internet: LEVY@FNALD.FNAL.GOV   |       as an Etch-a-Sketch is to art.       ]
[ HEPnet/SPAN: FNALD::LEVY (VMS!) |                                            ]
================================================================================
From: sburton@dres.dnd.ca (Stan Burton)
Subject: Re: Radar detector DETECTORS?
Content-Type: text/plain; charset=iso-8859-1
Nntp-Posting-Host: stan
Content-Transfer-Encoding: 8bit
Organization: Defence Research Establishment Suffield
X-Newssoftware: GRn-beta 1.16g (04.01.93) by Michael B. Smith & Mike Schwartz
Mime-Version: 1.0
Distribution: na
Lines: 25
In article <1993Apr14.181738.18472@bmers95.bnr.ca> alee@bmerh794.bnr.ca (Louis Leclerc) writes:
>
> In article <34263@oasys.dt.navy.mil> you write:
> >VA, CT, Wash DC  and I think BC Canada where I've heard they actually
> >use Radar detector detectors.
>
> Nope, not in British Columbia.  Detectors are legal here in BC, I've even
> got one.
>
> In Alberta and Ontario they're illegal, and detection devices are sometimes
> used.  I've heard the police in Ontario prefer a much more direct method of
> detection.  Just trigger the radar gun, watch for people slamming on the
> brakes, and search the car.
>
>
> David Lee
> leex@sfu.ca
>
Detectors are legal in Alberta, the old law was overturned a long time ago.
--
Stan Burton (DND/CRAD/DRES/DTD/MSS/AGCG)                 sburton@dres.dnd.ca
(403) 544-4737     DRE Suffield, Box 4000, Medicine Hat, AB, Canada, T1A 8K6
From: harton@owlnet.rice.edu (Tracy Brian Harton)
Subject: Wireless Transmitter/Receivers at RS
Organization: Rice University
Lines: 12
Does anyone know what frequencies the wireless transmitter/receiver
microphone systems that Radio Shack sells operate at?  I've tried
everything short of opening one up (not actually owning one makes
this difficult...) and just looking..  Any help would be greatly
appreciated..  These systems are designed for wireless PA systems, etc..
Thanks,
Tracy
From: st1my@rosie.uh.edu (Stich, Christian E.)
Subject: Re: Motorola XC68882RC33 and RC50
Organization: University of Houston
Lines: 26
Distribution: world
NNTP-Posting-Host: rosie.uh.edu
Keywords: Motorola, FPU, 68882, 68030, 33/50 MHz, problems (FPU exception)
News-Software: VAX/VMS VNEWS 1.41
In article <16APR199323531467@rosie.uh.edu>, st1my@rosie.uh.edu (Stich, Christian E.) writes...
>I just installed a Motorola XC68882RC50 FPU in an Amiga A2630 board (25 MHz
>68030 + 68882 with capability to clock the FPU separately).  Previously
>a MC68882RC25 was installed and everything was working perfectly.  Now the
>systems displays a yellow screen (indicating a exception) when it check for
>the presence/type of FPU.  When I reinstall an MC68882RC25 the system works
>fine, but with the XC68882 even at 25 MHz it does not work.  The designer
>of the board mentioned that putting a pullup resistor on data_strobe (470 Ohm)
>might help, but that didn't change anything.  Does anybody have some
>suggestions what I could do?  Does this look like a CPU-FPU communications
>problem or is the particular chip dead (it is a pull, not new)?
>Moreover, the place I bought it from is sending me an XC68882RC33.  I thought
>that the 68882RC33 were labeled MC not XC (for not finalized mask design).
>Are there any MC68882RC33?
>
>Thanks
>	Christian
>
It appears as if the problem is related to the 68882/50's need for very fast
(and clean) signal transitions.  I got some email (Vielen Dank, Thomas) stating
that Motorola provides a solution for this problem in their 68030 manual.
Since my manual (1989) predates the 50 MHz 68030/68882s I couldn't find it.
Could someone please email me the specifics?
Thanks
Christian
From: mont@netcom.com (Mont Pierce)
Subject: Re: 8051 Microcontroller
Organization: Netcom - Online Communication Services (408 241-9760 guest)
Lines: 31
In article <1qppr5INNaqa@dns1.NMSU.Edu> mcole@spock (COLE) writes:
>I would like to experiment with the INTEL 8051 family.  Does anyone out
>there know of any good FTP sites that might have compiliers, assemblers,
>etc.?
Well, it's not an FTP site, but I got an 800 number for Signetics BBS.
The Signetics BBS contain some pretty good items for the 8051.  I am
currently using the following files which I downloaded from them:
ml-asm51.zip      MetaLink's 8051 family macro assembler
bootstrp.zip      Hex file Load-and-Go using 8051 uart
(allows you to download your program into a RAM
and then execute from RAM.  Works great.  Tell
me if you want more details).
tutor51.zip       TSR for 8051 feature help screens
They have lots of coding examples, assemblers, and misc. tools.
Signetics BBS numbers are:    (800) 451-6644
(408) 991-2406
Have fun,
--
Mont Pierce
+-------------------------------------------------------------------------+
| Ham Call: KM6WT             Internet:  mont@netcom.com                  |
|    bands: 80/40/20/15/10/2  IBM vnet:  mont@vnet.ibm.com                |
|    modes: cw,ssb,fm                                                     |
+-------------------------------------------------------------------------+
From: borowski@spk.hp.com (Don T. Borowski)
Subject: Re: help - how to construct home-built battery for 3rd grade sci report
Distribution: usa
Organization: Hewlett-Packard
X-Newsreader: TIN [version 1.1.4 PL6]
Lines: 20
Dean Anneser (anneser@pwa-b.uucp) wrote:
: My 9 yr old son has signed up to do a science report on batteries.  I was
: wondering if anyone could provide me with some information as to how to
: construct a home-built battery.  In my grade school days, I remember seeing
: the 'ice cube tray' version, but I don't remember what to use as a good
: electrolyte or what the easily obtainable metals were.
:
: Thank you in advance.
I remember watching a whole "Mr. Wizzard" program on this subject when
I was a kid.  The battery constructed on the program which made the
biggest impression on me, and generated the most power, was made using
a galvanized bucket (for the zinc) and a copper toilet tank float.  The
electrolyte was sauerkraut!
Donald Borowski    WA6OMI    Hewlett-Packard, Spokane Division
"Angels are able to fly because they take themselves so lightly."
-G.K. Chesterton
From: mont@netcom.com (Mont Pierce)
Subject: Need pinouts for a G8870 dtmf decoder chip
Organization: NETCOM On-line Communication Services (408 241-9760 guest)
Distribution: usa
Lines: 19
I bought this chip from Suncoast Technology and tried to build their
dtmf decoder circuit.  But it's not working...
If anyone has the pinouts and possibly the voltage specs I'd sure
appreciated it.  If someone could fax, email, or snail mail a copy
of the spec sheet for this chip that would be even better. :)
Please email me if you can help.
Thanks in advance,
--
Mont Pierce
+-------------------------------------------------------------------------+
| Ham Call: KM6WT             Internet:  mont@netcom.com                  |
|    bands: 80/40/20/15/10/2  IBM vnet:  mont@vnet.ibm.com                |
|    modes: cw,ssb,fm                                                     |
+-------------------------------------------------------------------------+
From: babb@sciences.sdsu.edu (J. Babb)
Subject: Cicuit Cellar Ink - Extras 4 Trade
Organization: SDSU - LARC
Lines: 14
Distribution: world
NNTP-Posting-Host: larc.sdsu.edu
Fellow Info-junkies,
I have an extra CCI #27 (Real Time Programming/Embedded Sensors &
Storage) and an extra CCI #32 (Voice control of telescope, among other
articles). No labels. No torn, cut-up, or missing pages.
Would like to trade for CCI # 26, or CCI # 23, or CCI # 19 in same
condition (Labels OK).
I mail mine you mail yours mutual trust kinda thang OK?
You don't actually throw them away, do you?
Thanx,
Jeff Babb
babb@sciences.sdsu.edu
From: garyg@warren.mentorg.com (Gary Gendel)
Subject: Re: Need to find out number to a phone lin
Organization: Mentor Graphics Corp. -- IC Group
Lines: 32
Distribution: world
Reply-To: garyg@warren.mentorg.com
NNTP-Posting-Host: garyg.warren.mentorg.com
In article 1qub4mINN7r3@rave.larc.nasa.gov, kludge@grissom.larc.nasa.gov (Scott Dorsey) writes:
>In article <20756.2bd16dea@ecs.umass.edu> alee@ecs.umass.edu writes:
>>
>>Greetings!
>>
>>        Situation:  I have a phone jack mounted on a wall.  I don't
>>                    know the number of the line.  And I don't want
>>                    to call up the operator to place a trace on it.
>>
>>        Question:   Is there a certain device out there that I can
>>                    use to find out the number to the line?
>
>
>Call a friend long distance, collect.  Ask to speak with yourself.  When
>the operator asks for you, you won't be there, so ask the operator to leave
>your number.  She'll read it out in the clear.
>--scott
Even easier, my area supports 311.  Dial this and a recording recites your number.
Phone techs use it to verify an installed line.
---
Gary Gendel
Vice President:				Current consulting assignment:
Genashor Corp				Mentor Graphics Corporation
9 Piney Woods Drive			15 Independence Boulevard
Belle Mead, NJ 08502			Warren, NJ 07059
phone:	(908) 281-0164			phone:	(908) 604-0883
fax:	(908) 281-9607			email:	garyg@warren.mentorg.com
From: yxy4145@ucs.usl.edu (Yu Yingbin)
Subject: Does someone know what is the news group for IEEE.
Organization: Univ. of Southwestern La., Lafayette
Distribution: usa
Lines: 2
yxy4145@usl.edu     Thanks a lot.
From: khairon@usc.edu (Rosli Bin Khairon)
Subject: Looking for Address of Noise Cancellation Tech.
Organization: University of Southern California, Los Angeles, CA
Lines: 14
Distribution: na
NNTP-Posting-Host: sal-sun130.usc.edu
I am new to this newsgroup so I apologise if this is not the appropriate
forum to ask this question. I am looking for the address of Noise Cancellation
Technologies. It is rather important. So if you can help me in this regard,
please do. Thank you.
-- Rosli
Khairon@aludra.usc.edu
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Motorola XC68882RC33 and RC50
Organization: U of Toronto Zoology
Lines: 14
In article <sgberg.23xu@charon.bloomington.in.us> sgberg@charon.bloomington.in.us (Stefan Berg) writes:
>... I don't know why my FPU has an XC (my original 33MHz FPU
>was label MC68882-33), but it seems to work fine on my system...
>P.S. Or does it mean eXperimental Chip instead of Motorola Chip? .-)
The rule for the designations is that if it says MC, that means it works
*exactly* the way the datasheet/book specifies.  If it says XC, that means
there is at least one known bug.  Often these bugs are small and obscure;
you might never run into them in practice.
At least Motorola admits it, unlike certain other companies...
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
- Kipling           |  henry@zoo.toronto.edu  utzoo!henry
From: willisw@willisw.ENG.CLEMSON.edu (Bill Willis)
Subject: Re: Mysterious MOSFET
Organization: Engineering Services, Clemson University
Lines: 23
In article <1qug3sINN90g@rave.larc.nasa.gov> kludge@grissom.larc.nasa.gov (Scott Dorsey) writes:
>I have a MOSFET pulled out of a Trygon power supply, for which I have no
>manual.  It's a Motorola part with a 1972 date code and the number
>               285-4
>which the Motorola folks assure me is a house number, which they can't
>help me with.  Any suggestions from folks out there?  I can't put it on
>a curve tracer to try to get an equivalent, since it's completely shot.
>--scott
Since your MOSFET is a 1972 vintage, it's probably not a very good one by
today's standards.  If you have an idea about its voltage and current
ratings, e.g. 60VDC @ 6A, you can probably get away with replacing it with
anything with better specs.  Early MOSFETS had a gate-source voltage rating
of approximately +/- 20 VDCmax, and they would usually turn completely "ON"
at +10VDC.  Otherwise, MOSFETS are not really mysterious -- they're more or
less voltage controlled current sources.  If the MOSFET in your circuit is
used as an open-loop, voltage controlled current source, you may have to
experiment with various gain-altering techniques.
Bill Willis     willisw@coe-nw.clemson.edu
(803) 656-5550
From: kubovich@iastate.edu (Mark W Kubovich)
Subject: Common-mode noise and small signals
Keywords: noise common mode
Organization: Iowa State University, Ames IA
Lines: 20
I have never worked with really small signals before and have a few
questions about low level noise.  I have noticed that the waveform
synthesizer that I am using (Analogic 2020) has some relatively large
common mode noise on it.  I am using this synthesizer to 'null' out another
transient waveform and am amplifying the difference (~200uV) several hundred
times.  The 2020 has about 1-3 mVp-p of common mode noise and this tends to
make my measurements hard to repeat.  (The noise is not quite in sync with
line frequency, and on a spectrum analyzer, the main component is about 64Hz).
How can I get rid of the noise?  When I look at the spectrum using an
HP 3582A (audio range analyzer), the noise goes away the minute I switch to
'isolation' on the input.  I am guessing the anlayzer has a diff amp on the
input since it will read accurately down to DC.
Also, if I use a differential amplifier (IA) to solve the problem,
how important is it to use one of these 'shield drivers' (an amp connected
to the shield in sort of a feedback loop to remove trouble caused
by different cable capacitances)?  If anyone can suggest a good IC IA for
use with transient signals with content from 1KHz to about 300KHz, I would
appreciate it.
From: bday@lambda.msfc.nasa.gov (Brian Day)
Subject: Re: 8051 Microcontroller
Organization: NASA/MSFC
Lines: 12
mcole@spock (COLE) writes:
>I would like to experiment with the INTEL 8051 family.  Does anyone out
>there know of any good FTP sites that might have compiliers, assemblers,
>etc.?
Try lyman.pppl.gov -- /pub/8051
--
Brian Day                                       bday@lambda.msfc.nasa.gov
New Technology, Inc.                            (205) 461-4584
Mission Software Development Division           Opinions are my own -
From: Wayne Alan Martin <wm1h+@andrew.cmu.edu>
Subject: Re: Dayton Hamfest
Organization: Senior, Electrical and Computer Engineering, Carnegie Mellon, Pittsburgh, PA
Lines: 5
Distribution: usa
NNTP-Posting-Host: po5.andrew.cmu.edu
In-Reply-To: <1993Apr19.163122.20454@cbfsb.cb.att.com>
Yes, it is the 23, 24 and 25, in but does anyone have directions how to
get there after I get to Dayton.  Thanks
Wayne Martin
From: jkaidor@synoptics.com (Jerome Kaidor)
Subject: Re: electronic odometers (was: Used BMW Qu
Reply-To: jkaidor@synoptics.com
Organization: SynOptics Communications, Santa Clara CA
Lines: 31
Nntp-Posting-Host: picasso.synoptics.com
Just a few comments about the feasability of zipping up a bunch of miles
on your electronic odometer with an oscillator....
I wouldn't expect to be able to do this.  Not because the engineers at BMW are
putting in anti-fraud logic, but just because an automobile is a noisy, hostile
environment for electronics, and I would expect the software to be conservative.
If I were to design a microprocessor-based odometer/speedometer program,
it would have the following features ( just off the top of my head ):
* Debouncing/deglitching  ( Is this a real pulse, or just a glitch? )
* Smoothing:  The rate-of-change of speed cannot be too high:
This is a car, not an electron.
*  Top speed limit:  Anything above 200MPH is ridiculous: must be
electrical noise or contact bounce
As for getting in and presetting the pins:  if this is the circuit board out of
a BMW dashboard, I seem to remember a single big chip with lotsa pins in the
middle of the card.  Good luck getting at the counter :-).
I wouldn't expect a high input frequency to damage the meter:  remember, it's
probably damped so it can't move too fast, and is probably protected.  After all,
a car is an extremely hostile place for delicate electronics;  there used to be an
app note in the National Semiconductor Linear Databook that went into this
in good detail.
- Jerry Kaidor ( tr2!jerry@dragoman.com, jkaidor@synoptics.com )
- Jerry Kaidor
From: 2575brooksr@vms.csd.mu.edu
Subject: NeXT cube board monitor cable ?
Organization: Marquette University - Computer Services
Lines: 8
Reply-To: 2575brooksr@vms.csd.mu.edu
NNTP-Posting-Host: vmsf.csd.mu.edu
Hi all!
Quick question.  Could someone please send me a pinout of
the cable that goes between a NeXT cube and the monitor?  Also,
I am interested in the video signal (sync type, horz/vert rate)
so any information on that would be greatly appreciated also.
Thanks!
Ryan Brooks					ryan@agnus.mcs.mu.edu
From: alung@megatest.com (Aaron Lung)
Subject: Re: Need to find out number to a phone line
Organization: Megatest Corporation
Lines: 24
In article <20756.2bd16dea@ecs.umass.edu> alee@ecs.umass.edu writes:
>
>Greetings!
>
>        Situation:  I have a phone jack mounted on a wall.  I don't
>                    know the number of the line.  And I don't want
>                    to call up the operator to place a trace on it.
>
>        Question:   Is there a certain device out there that I can
>                    use to find out the number to the line?
>        Thanks for any response.
>                                                    Al
There is a number you can call which will return a synthesized
voice telling you the number of the line.  Unfortunately, for the
life of me I can't remember what it is. The telephone technicians
use it all the time.  We used to play around with this in our
dorm rooms since there were multiple phone lines running between
rooms.
sorry!
aaron
From: musone@acsu.buffalo.edu (Mark J. Musone)
Subject: MC SBI mixer
Organization: UB
Lines: 20
Nntp-Posting-Host: autarch.acsu.buffalo.edu
HI, I was wondering if anyone would be able to help me on twwo related
subjects. I am currently learning about AM/FM receivers and recieving
circuits. I understand a lot of things ,but a few things I am confused
abuot. The first is the MIXER, to mix the RF and local oscillator
frequencies to make the IF. Does anyone have any cicruit diagrams (as
simple as possible) for this kind of mixer? I have come across a
MC-SBL mixer chip But I have not been able to find it in any catalogs
(ACTIVE,etc...)
Along the same note, are there any SIMPLE fm receiver circuits anyone
may have stashed away somewhere and they couold let me see?.
P.S. any REALLY GOOD BOOKS on AM/FM theory ALONG WITH DETAILED
ELECTRICAL DIAGRAMS would help a lot.
I have seen a lot of theory books with no circuits and a lot of
circuit books with no theory, but one without the other does not help.
Thanks,
Mark Musone
From: levy@levy.fnal.gov (Mark E. Levy, ext. 8056)
Subject: Sources for Intel D87C51FB?
Nntp-Posting-Host: levy.fnal.gov
Organization: Fermilab Computing Division
Lines: 18
I am in the midst of designing a project which requires two motors and an LED
illuminator driven with Pulse-width modulation.  I'm using the 8751, and
I understand that the -FB version has a programmable counter array that can
essentially be set and forgotten to do the PWM.  The problems is, that variant
is difficult to come by.  I need two or three of the D prefix (ceramic window)
version for development, and then lots of the P prefix (plastic OTP) for later
production.  I've tried Avnet, Arrow, and Pioneer.  They (might) have them, but
I'm looking for samples at this point, and they're not too willing to provide
them.  I would buy them, but these vendors have $100.00 minimums.
Any help is appreciated.
================================================================================
[ Mark E. Levy, Fermilab          |                                            ]
[ BitNet:   LEVY@FNAL             | Unix is to computing                       ]
[ Internet: LEVY@FNALD.FNAL.GOV   |       as an Etch-a-Sketch is to art.       ]
[ HEPnet/SPAN: FNALD::LEVY (VMS!) |                                            ]
================================================================================
From: jott@scarecrow.cse.nd.edu (John Ott)
Subject: Re: Pinout needed for TIL311
Reply-To: jott@scarecrow.cse.nd.edu (John Ott)
Organization: Univ. of Notre Dame
Lines: 64
In article <segal.734995860@corolla7>, segal@rtsg.mot.com (Gary Segal) writes:
|> I've recently picked up some TIL311 display chips, but I can't find
|> any information on them.  It seems they are no longer made by TI, and
|> I don't have an old enough data book.  :-(
|>
|> It appears to have a dot-matrix led display capable of showing one hex
|> digit.  It is in a 14 pin DIP package, but pins 6, 9, and 11 are not
|> present.
|>
|> If you have any information on this part (pinout, power requirments,
|> functions, ...) please send me e-mail.
|>
|> Thank You,
|>
|> --
|> Gary Segal                             Motorola Inc.
|> segal@oscar.rtsg.mot.com               Cellular Infrastructure Division
|> 	--- we are standing here only to gaze at the wind ---
pin      function
1      led supply voltage
2      latch data input b
3      latch data input a
4      left decimal point cathode
5      latch strobe input
6      omitted
7      common gnd
8      blanking input
9      omitted
10      right decimal point cathode
11      omitted
12      latch data input d
13      latch data input c
14      logic supply voltage (5v)
LATCH STROBE INPUT, pin 5, when low, the data in the latches follow the data on the latch data
inputs.  When high, the data in the latches will not change.  If the
display is blanked and then restored while the enable input is high,
the previous character will again be displayed.
BLANKING INPUT, pin 8,    When high, the display is blanked regardless of the levels of the other
inputs.  When low, a character is displayed as determined by the data
in the latches.  The blanking input may be pulsed for intensity modulation.
LATCH DATA INPUTS, pins 2,3,12,13,   Data on these inputs are entered into the latches when the enable
input is low.  The binary weights of these inputs are A = 1,
B = 2, C = 4, D = 8
DECIMAL POINT CATHODES, pins 4, 10,   These LEDS are not connected to the logic chip.  If a decimal point
is used, an external resistor or other current limiting
mechanism must be connected in series with it.
LED SUPPLY, pin 1            This connection permits the user to save on regulated Vcc current by using
a separate LED supply, or it may be externally connected to the logic
supply (Vcc).
LOGIC SUPPLY (Vcc), pin 14      Separate Vcc connection for the logic chip
COMMON GROUND, pin 7,      This is the vegative termnal for all logic and LED currents except for the
decimal points.
John
jott@dickens.helios.nd.edu
From: tron@ux1.cso.uiuc.edu (Tron R.)
Subject: modulation over rf
Organization: University of Illinois at Urbana
Lines: 11
I would like to modulate a 40KHz squarewave over rf. This is for a rf
remote control project. The squarewave has a high of 5 v and low of 0v.
thanks.
tron
--
T
T     T
T  T  T
T  T  T
From: morrow@cns.ucalgary.ca (Bill Morrow)
Subject: Need source for old Radio Shack stereo amp chip
Nntp-Posting-Host: cns9.cns.ucalgary.ca
Organization: University of Calgary
Lines: 13
Last week I asked for help in getting an old homemade amp working with
my Sun CD-ROM drive. It turns out that the channel I was testing with
was burned out in the amp. The other channel works fine.
So now I need a new amplifier chip. My local Radio Shack no longer
carries components! The chip is a 12 pin SIP (?) labelled with BA5406
and then "502 515" below that.
Does anyone have a source? Thanks,
--
Bill Morrow    Clinical Neurosciences, University of Calgary
e-mail: morrow@cns.ucalgary.ca voice: (403) 220-6275 fax: (403) 283-8770
3330 Hospital Drive NW Calgary, Alberta, CANADA T2N 4N1
From: msunde01@mik.uky.edu (Mark  Underwood)
Subject: Re: help - how to construct home-built battery for 3rd grade sci report
Nntp-Posting-Host: nx26.mik.uky.edu
Reply-To: msunde01@mik.uky.edu
Organization: University Of Kentucky, Dept. of Math Sciences
Distribution: usa
Lines: 29
In article <C5quI4.4CF@spk.hp.com> borowski@spk.hp.com (Don T. Borowski)
writes:
> Dean Anneser (anneser@pwa-b.uucp) wrote:
> : My 9 yr old son has signed up to do a science report on batteries.  I
was
> : wondering if anyone could provide me with some information as to how
to
> : construct a home-built battery.  In my grade school days, I remember
(snip!)
I haven't been following this, so I'm sorry if somebody already mentioned
this, but you could grab a lemon (I think potatoes work too, but I'm not
sure), a strip of copper, and a strip of zinc (I think you can get the
metal in a hardware store or hobby shop, maybe??).  Stick the strips in
the lemon (so they don't touch!) and you'll get a measurable voltage (not
a lot, but, hey, it's a lemon :-)  ).  As I recall we had to hook
something like ten of these things to get an appreciable amount of
current, because of the mondo internal resistance, but if you just need a
demo you might get it to run a tiny fan or something! :-)
Mark S. Underwood
EE Student, University of Kentucky
Lab Assistant, Boyd Hall Microlab
(a tiny little division of UK Library Microlabs)
E-Mail:  msunde01@mik.uky.edu
From: schuch@phx.mcd.mot.com (John Schuch)
Subject: Re: Need pinouts for a G8870 dtmf decoder chip
Nntp-Posting-Host: bopper2.phx.mcd.mot.com
Organization: Motorola Computer Group, Tempe, Az.
Distribution: usa
Lines: 59
In article <montC5qs9A.3wB@netcom.com> mont@netcom.com (Mont Pierce) writes:
>
>I bought this chip from Suncoast Technology and tried to build their
>dtmf decoder circuit.  But it's not working...
>
>If anyone has the pinouts and possibly the voltage specs I'd sure
>appreciated it.
I presume it is the M-8870 from Teltone Corporation.
Pin	Description
1	+ input
2	- input
3	GS (gain select through use of feed back resistor)
4	Vref (reference voltage OUTPUT, about Vdd/2)
5	connect to Vss
6	connect to Vss
7	osc1 clock input
8	osc2 clock output (connect crystal across pins 7 and 8)
9	Vss
10	OE output enable (logic high allows data output)
11	Q1 data output
12	Q2 data output
13	Q3 data output
14	Q4 data output
15	StD Delayed Steering Output (any other company would call this 'data valid'.)
16	ESt Early Steering output, sort of like "I'm starting to hear a tone".
17	St/GT Steering input/guard time output
18	Vdd
Power Supply	: 4.75V min., 5.25V max.
Current		: 3.0mA Typ, 7.0mA max.
BUT.......
You really should have bought the Motorola part from me.  :-)
(I still have them in stock)
John
If someone could fax, email, or snail mail a copy
>of the spec sheet for this chip that would be even better. :)
>
>Please email me if you can help.
>
>Thanks in advance,
>--
>Mont Pierce
>
>+-------------------------------------------------------------------------+
>| Ham Call: KM6WT             Internet:  mont@netcom.com                  |
>|    bands: 80/40/20/15/10/2  IBM vnet:  mont@vnet.ibm.com                |
>|    modes: cw,ssb,fm                                                     |
>+-------------------------------------------------------------------------+
Subject: Pattern Generator wanted
From: grimwood@ccu1.aukuni.ac.nz (Tony Grimwood)
Organization: University of Auckland, New Zealand.
Keywords: pattern
Summary: MDA/EGA/VGA pat. gen.
Lines: 15
I repair a lot of monitors here, and I'd like to know where I can get a
pattern generator (or a circuit for one) that will provide MDA, EGA and VGA
signals. Using a whole PC to do this takes up too much space on my bench, and
is somewhat less than portable. I guess I could sit down and design something,
but I don't have the time right now - any (reasonable) suggestions would be
appreciated.
TNX
TG
--
Tony Grimwood, ZL1TTG			"Make no friendship with an elephant
Biomedical Engineering Services		 keeper, unless you have room to
University of Auckland			 entertain an elephant."
Auckland, New Zealand		       		 == Saadi of Shiraz ==
From: howeg@p4.cs.man.ac.uk (Monty Mole)
Subject: FM Transmitter
Keywords: Old question I know
Lines: 14
Can anyone please email a diagram or give me details of an ftp site where there
is a diagram of a simple, small fm mono voice transmitter for trasnmitting in
the 90-104 range (preferably above 100 Mhz). Only a short distance requiered,
and frequency variation no too important but must run from 9v or smaller DC
supply.
Thanx in advance
Monty.
--
/\    /\     __   __  /_                            howeg@uk.ac.man.cs
/  \  /  \   /  / / / /  / /                         howeg@cs.man.ac.uk
__/    \/    \_/__/_/ /_/__/_/____________________________________________
____________________________/ Save The Vinyl!
From: alung@megatest.com (Aaron Lung)
Subject: Re: Suggestions  on Audio relays ???
Organization: Megatest Corporation
Lines: 23
In article <C5qsBF.IEK@ms.uky.edu> billq@ms.uky.edu (Billy Quinn) writes:
>I built a little project using the radio shack 5vdc relays to switch
>audio.  I got pretty bad 'clicks' when the thing switched.  I was doing
>most of the common things one is supposed to do when using relays and
>nothing seemed to get rid of the clicks.
>
>
>My question is:
>
>	Is there a good relay/relay circuit that I can use for switching
>audio, so that there will be *NO* noise of any kind on the audio lines.
>
>
>I will appreciate any advice or references to advice.  Also, exact part
>numbers/company names etc. for the relays will help!
Are you switching high level signals or low level signals like pre-amp
out level signals?  Also, are the clicks you mentioning the big
clack that happens when it switches or are you refering to contact
bounce?  How are you driving the relays?  TTL gate output?  Switching
transistor?  How are the relays connected to what you are driving?
Need more specifics to answer your question!! :-)
From: loving@lanai.cs.ucla.edu (Mike Loving)
Subject: specs on eprom data formats
Nntp-Posting-Host: lanai.cs.ucla.edu
Organization: UCLA, Computer Science Department
Lines: 10
I need the specs on various eprom data formats such as Intel Hex, Motorola S
JEDEC etc.
Can anyone out there provide such info or a pointer to it?
The one I want the most is Intel Hex.
Mike
From: payne@crl.dec.com (Andrew Payne)
Subject: WANTED:  TCM3105 chips, small quantities
Organization: DEC Cambridge Research Lab
Lines: 16
Does anyone know if a source for the TCM3105 modem chips (as used in the
Baycom and my PMP modems)?  Ideally, something that is geared toward
hobbyists:  small quantity, mail order, etc.
For years, we've been buying them from a distributor (Marshall) by the
hundreds for PMP kits.  But orders have dropped to the point where we can
no longer afford to offer this service.  And all of the distributors I've
checked have some crazy minimum order ($100, or so).
I'd like to find a source for those still interested in building PMP kits.
Any suggestions?
--
Andrew C. Payne
DEC Cambridge Research Lab
From: babb@rapnet.sanders.lockheed.com (Scott Babb)
Subject: Re: Radar detector DETECTORS?
Organization: Lockheed Sanders
X-Newsreader: TIN [version 1.1 PL9]
Distribution: na
Lines: 24
Brian Day (bday@lambda.msfc.nasa.gov) wrote:
: On December 29, 1992, it was illegal to operate a radar detector
: in the state of Virginia.  If one got caught, one got fined $65.00.
: Ask me how I know.
The Federal Communications Act of 1934 made it *legal* for you to
operate a radio receiver of any kind, on any frequency (including
X, K, and Ka bands) in the United States.  The Electronic
Communications Privacy Act of 1989(?) restricted the FCA of 1934
by making it illegal to receive the land-mobile telephone service,
including (I believe) cellular phones.  No restriction was placed
on receiving RADAR (or, curiously, cordless phones.)  Enforcement
of the Virginia law is in violation of the FCA of 1934.  If you have
lots of time and money (and a lawyer, which I'm *not*,) you can
argue this in a federal court and try to have the law overturned.
I can hardly wait to see the responses to this one, but somebody
had to say it...
--
Lockheed Sanders may disagree so these are solely the opinions of:
Scott L. Babb - babb@rapnet.sanders.lockheed.com
"We didn't inherit the Earth from our parents,
we are borrowing it from our children."
From: jhawk@panix.com (John Hawkinson)
Subject: Building a UV flashlight
Organization: PANIX Public Access Unix, NYC
Lines: 23
Yes, I know it sounds crazy. Call it an urge. Call it what you want.
Just don't ask why :-)
Anyway, I'd like to build a UV flashlight, cheaply. "flashlight" means
it should be reasonably portable, but could have a power pack if
necessary.
My main question is the bulb: where can I get UV bulbs? Do they
need a lot of power? etc., etc.
I'm not too concerned with whether it's long-wave or short-wave
(but hey, if anyone has a cheap source of bulbs, I'll take both).
One other thing: a friend of mine mentioned something about near-UV
light being cheaper to get at than actual UV light. Does anyone
know what he was referring to?
Thanks much.
--
John Hawkinson
jhawk@panix.com
From: ptorre@hardy.u.washington.edu (Phil Torre)
Subject: Circuit Cellar Ink address?
Organization: University of Washington, Seattle
Lines: 2
Distribution: na
NNTP-Posting-Host: hardy.u.washington.edu
Summary: Address or phone number for subscriptions?
Is CCI still published?  If so, does anyone have their address?
From: wlsmith@valve.heart.rri.uwo.ca (Wayne Smith)
Subject: Re: Radar detector DETECTORS?
Organization: The John P. Robarts Research Institute, London, Ontario
Distribution: na
Nntp-Posting-Host: valve.heart.rri.uwo.ca
Lines: 21
In article <1993Apr19.231050.2196@Rapnet.Sanders.Lockheed.Com> babb@rapnet.sanders.lockheed.com (Scott Babb) writes:
>
>The Federal Communications Act of 1934 made it *legal* for you to
>operate a radio receiver of any kind, on any frequency (including
>X, K, and Ka bands) in the United States.  The Electronic
>Communications Privacy Act of 1989(?) restricted the FCA of 1934
>by making it illegal to receive the land-mobile telephone service,
>including (I believe) cellular phones.
Illegal to receive land-mobile telephone service?  Don't you have to have a
mobile reciever to even have land-mobile telephone service?  What about
ship-to-shore telephone service?
>No restriction was placed
>on receiving RADAR (or, curiously, cordless phones.)  Enforcement
>of the Virginia law is in violation of the FCA of 1934.
Isin't there some kind of rule (regulation, law, whatever) in some
juristictions that prohibit the use of *police band* recievers
in vehicles?  And that radar transmissions are included in the police band
so they get covered by the same regulation?
From: Kirk_Cowen@panam.wimsey.bc.ca (Kirk Cowen)
Subject: references...
Distribution: world
Organization: Commodore Computer Club / PaNorAmA
Lines: 12
I've got the same problem; I can't dig up any info on the jumper settings
on the hd 3.5" drives.
Can anyone recommend a reference book(s) on the subject, rather than a
"quick fix" type answer??  I was going to start hooking up things and
logging the results, but the prospect of a ten second smoke test deters
me...
Thanks, Kirk Cowen.
-- Via DLG Pro v0.995
From: alung@megatest.com (Aaron Lung)
Subject: Re: Motorola XC68882RC33 and RC50
Organization: Megatest Corporation
Lines: 21
In article <C5qwv2.Bz0@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>In article <sgberg.23xu@charon.bloomington.in.us> sgberg@charon.bloomington.in.us (Stefan Berg) writes:
>>... I don't know why my FPU has an XC (my original 33MHz FPU
>>was label MC68882-33), but it seems to work fine on my system...
>>P.S. Or does it mean eXperimental Chip instead of Motorola Chip? .-)
>
>The rule for the designations is that if it says MC, that means it works
>*exactly* the way the datasheet/book specifies.  If it says XC, that means
>there is at least one known bug.  Often these bugs are small and obscure;
>you might never run into them in practice.
>
XC units are often pre-production sample devices.  Those are normally
distributed for evaluation as freebies and are not guaranteed to
meet every spec.
>At least Motorola admits it, unlike certain other companies...
Yep, that's for sure...that's one thing I like most about Motorola.
aaron
From: mont@netcom.com (Mont Pierce)
Subject: Re: 8051 Microcontroller
Organization: Netcom - Online Communication Services (408 241-9760 guest)
Lines: 20
In article <1993Apr19.194525.3888@lambda.msfc.nasa.gov> bday@lambda.msfc.nasa.gov (Brian Day) writes:
>mcole@spock (COLE) writes:
>
>>I would like to experiment with the INTEL 8051 family.  Does anyone out
>>there know of any good FTP sites that might have compiliers, assemblers,
>>etc.?
>
>Try lyman.pppl.gov -- /pub/8051
Great.  This site is a complete shadow of the Signetics BBS 8051 directory.
Thanks Brian,
--
Mont Pierce
+-------------------------------------------------------------------------+
| Ham Call: KM6WT             Internet:  mont@netcom.com                  |
|    bands: 80/40/20/15/10/2  IBM vnet:  mont@vnet.ibm.com                |
|    modes: cw,ssb,fm                                                     |
+-------------------------------------------------------------------------+
From: jmc@engr.engr.uark.edu (J. M. Carmack)
Subject: RE: Exploding TV
Nntp-Posting-Host: engr.engr.uark.edu
Organization: University of Arkansas
Lines: 21
Just a thought........Maybe it possibly has to do with the fact that it
IS an Emerson.  I've got an Emerson VCR which is #6 in the series.  Returned
it six times for various and never the same problems.  Got tired of taking it
back and fixed it myself.  The Hi-Fi "window" was a bit off.  Something like
the Hi-Fi audio fine-tuning.  When I was a Wal-Mart "associate" in '88-'89,
we had AT LEAST one returned as defective EVERY SINGLE DAY.  How's that for
reliability?  Face it--Emerson can make audio stuff (albeit not of premium
quality), but they CAN'T make anything as complex as video equipment with
reliability IMHO.  Please, no flames.  Just *had* to share my Emerson disaster
in the light of this exploding tv.
JC
--
-----------------+---------------+-------------+--------------+---------------
La Vie -- C'est Une Plage!  |  ?Caffine Not Present Error | jmc@engr.uark.edu
This Message Printed on     |  Abort, Retry, Fail ?       |
100% recycled electricity.  |                             |  Tangerine!!
From: Sean_Oliver@mindlink.bc.ca (Sean Oliver)
Subject: Re: Need to find out number to a phone line
Organization: MIND LINK! - British Columbia, Canada
Lines: 28
> Joseph Mich Krzeszewsk writes:
>
> Msg-ID: <1quomg$f6m@bigboote.WPI.EDU>
> Posted: 19 Apr 1993 17:49:04 GMT
>
> Org.  : Worcester Polytechnic Institute
>
> Well, this is my second try at posting on this subject. Here goes...
>         In Texas (Corpus Christi at least) if you pick up the phone and
> dial
>         890 the phone company will read the number of the phone you are on
>         back to you. I believe the service department uses this to make
>         certain they are repairing the correct lines when they open the BIG
>         junction boxes. I don't know if it will work but you can give it a
>         try. Good luck.
>
>
Where I live, I use BCTEL. The number to dial is 211 for the same result.
--
+--------------------------------------------+
| Sean Oliver                                |
| Internet Address: a8647@MINDLINK.BC.CA     |
|                                            |
| Mindlink! BBS (604)576-1412                |
+--------------------------------------------+
From: mtrek@netcom.com (Chuck L. Peterson)
Subject: 40MHZ Oscilloscope FOR SALE
Organization: NETCOM On-line Communication Services (408 241-9760 guest)
Lines: 11
I'm giving up hardware design and
am selling my Oscilloscope:
BK Precision  Model 1541B
40 MHZ Dual-Trace
Barely Used
$450 firm   (Fry's sells it for $589+tax)
Prefer people in Silicon Valley, so I don't have to ship it.
mtrek@netcom.com
From: jdz1@Ra.MsState.Edu (John D. Zitterkopf)
Subject: Info: NEC70001AB Amp. IC & ~20W AMP secs & possible PSPICE models
Keywords: Audio, AMPS
Nntp-Posting-Host: ra.msstate.edu
Organization: Mississippi State University
Lines: 40
Hi,
Being a Electronic Engineering Student with only Electronic II under
my belt, I find myself *needing* to build a moderate wattage Audio Amp. So,
I'll throw out a couple of question for the vast knowledge of the 'net'!
Please Explain how Watts are calculated in Audio Amp circuits. No,
Not P=I*E, Just how it relates to one of the following:
Ai [Current Gain]
Av [Voltage Gain]
Ap [Power Gain]
or whatever.
I already have a ?wonderful? cheap I.E <$20 schematic for a 20W amp, but
I would like to Cross/improve the circuit. The problem is that the parts
list has IC1 and IC2 as NEC70001AB amplifiers. They look like ?11 pin?
SIP packages with a heatsink. This schematic was published in a 1991 mag
so it may be non-existant now. Anyway, I tried looking up a replacement in
the latest Digi-key Cat and found it  not listed 8(. The closes I could
figure was a 9 pin SIP as TDA1520BU. Anyone got any Ideas?
I thought, hey I can rin a PSPICE simulation using 741 opamp
models. Yea, great! It worked. But, I guess the 741 wasn't made for High
power amps. As a result, I got a Voltage gain of ~15mV/V. Worse than
I started with 8(... Does anyone have a PSPICE CKT file with cheap yet
good gain? How about some models for some of the chips listed in this
E-mail? Any ASCII Chip info you guys can send me?
I'm open to Suggestions/Ideas/Comments/Help!
Please E-mail since I have little time to search the News...
And I'll post if there's and interest!
John
--
____________   _------_  |||IBM & |      EE majors Do it Best 8-)
--------\\ ] ~-______-~ |||Atari |~~~~~~~~~John D. Zitterkopf~~~~~~~~~~~~~
(~~~~~\\|_(__ ~~    / | \Rules!jdz1@ra.MsState.edu  jdz1@MsState.bitnet
\______| (        /  |  \    |AOL: zitt@aol.com  jdz1@isis.MsState.edu
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Radar detector DETECTORS?
Organization: U of Toronto Zoology
Lines: 17
In article <1993Apr20.022922.11861@julian.uwo.ca> wlsmith@valve.heart.rri.uwo.ca (Wayne Smith) writes:
>>No restriction was placed
>>on receiving RADAR (or, curiously, cordless phones.)  Enforcement
>>of the Virginia law is in violation of the FCA of 1934.
>
>Isin't there some kind of rule (regulation, law, whatever) in some
>juristictions that prohibit the use of *police band* recievers
>in vehicles?  And that radar transmissions are included in the police band
>so they get covered by the same regulation?
Those rules/regulations/laws would be subject to the same attack:  that
they are attempting to preempt federal authority to regulate (or not)
radio communications.  Of course, as the original poster noted, court
challenges of this kind can get expensive.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
- Kipling           |  henry@zoo.toronto.edu  utzoo!henry
From: randall@informix.com (Randall Rhea)
Subject: Re: Power, signal surges in home...
Organization: Informix Software, Inc.
Lines: 39
gstovall@crchh67.NoSubdomain.NoDomain (Greg Stovall) writes:
>Anyway, over the weekend, I was resting on the sofa (in between chores),
>and noticed that I briefly picked up what sounded like ham radio traffic
>over my stereo and television, even though both were off.  Also, all the
>touch sensitive lights in my house start going wacko, cycling through
>their four brightness states.
>I presume that some ham operator with an illegal amplifier drove past
>my house (I live on a busy thoroughfare); would this be a correct presumption?
>What kind of power must he be putting out to cause the effects?
>The affected equipment is about 100 feet from the road...
Hams can legally run up to 1500 watts.  It is very unlikely, however,
that a ham would be running that kind of power from a car.  Ham rigs
for cars put out around 100 watts.  It is possible that a 100 watt
radio would cause interference to consumer electronic 100 feet
away.  Most TVs, stereos, and VCRs have very poor RF shielding.
If you experience the problem frequently, it may be
caused by a ham, CBer, or other radio operator in a base station
nearby.    The interference may have been caused by a radio
transmitter used for other purposes, such as police, fire,
etc.  If you heard voices over your stereo, I think you are
correct in assuming that the source is an RF transmitter.
If you have frequent trouble, you may want to try the RF ferrite
chokes available at Radio Shack.  The interference is probably
being picked up by your speaker wires, and those chokes can
be installed on the wires very easily (without cutting them).
Good instructions are included with the chokes.
If that does not solve the problem, you may want to search your
neighborhood for a radio operator.  Look for antennas on the roof
or car.  Talk to him/her about your problem.  There are things
a radio operator can do to reduce interference.
--
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Randall Rhea                                        Informix Software, Inc.
Project Manager, MIS Sales/Marketing Systems    uunet!pyramid!infmx!randall
From: mg@cs.princeton.edu (Michael Golan)
Subject: how can 0.022 uF be different from two 0.047 in series?!
Originator: news@nimaster
Nntp-Posting-Host: elan.princeton.edu
Organization: Princeton University
Lines: 29
I was looking at the amps diagram for Sony 1090/2090 receivers, and I
was amazed to find a difference between the US and Canadian model
on the capacitor(s) that hangs off the output to the speakers:
------\/\/\----- to speaker (identical both models
from amp ---------------|
(idnetical both models) >
<  10
>
|
-----
|     |
0.022        ---   ---        Canadian model only!
US model        ---   --- 0.047
and world-wide   |     |
model only.      |    ---        Candian model only!
|    ---  0.047
|     |
----------- gound
The board itself is also identical, with room for all three caps. The
US/Can versions is clearly indicated in both places.
How does that make sense? 0.047/2 is 0.0235, essentially 0.022 for caps
(there are just standard caps, no special W/type/precision).
Please explain this
Michael Golan
mg@cs.princeton.edu
From: buhrow@moria.nfbcal.org (Brian Buhrow)
Subject: NEED HELP FINDING DIP SWITCH SETTINGS AND JUMPER SETTINGS FOR 386SX MOTHERBOARD
Keywords: JUMPER SETTINGS DIP-SWITCH SETTINGS, HELP, COMPUTER 386SX
Organization: National Federation of the Blind of California
Lines: 14
Hello net.  I have a 386sx motherboard with the Phoenix BIOS, an on-board
IDE controller port, and two on-board serial ports.  Unfortunately, I don't
have a manual for this beast and I would like to be able to disable the IDE
controller in order to use the MFM controller I have.
The board says it is made in Korea and it uses the Chips Chipset.  If
anyone can give me a clue as to how to go about configuring the board so as
not to use the IDE controller, or how to go about finding out how to do it,
their help would be greatly appreciated.
Thank you in advance for your assistance.
Please mail buhrow@nfbcal.org with your responses as my news feed is rather
tenuous.
Thank you very much!
-Brian <buhrow@nfbcal.org>
From: randy@ve6bc.ampr.ab.ca (Randy J. Pointkoski)
Subject: Needed 24 volt 4 circuit Flasher
Organization: Amateur Radio VE6BC
Lines: 17
I am looking for a source for a 4 circuit Sequence flasher.
Input 24 Volts AC, 8 amps
Output: sequence to 4 channels (knob to vary frequency) (max 2 amps
per leg)
Switch to put all channels on full time
Please Email any assistance you can provide.
Randy 			Email:  randy@ve6bc.ampr.ab.ca
--
__
/  )                                               Randy J Pointkoski P.Eng
/    __________  _   __  _  _   _   o ________      Compression Technologies
(__/ (_) / / / <_/_)_/ (_</_/_)_/_)_<_(_) / / <_     7141 77 ave
From: mgregory@flash.pax.tpa.com.au (Martin John Gregory)
Subject: HELP: MC146818A Real Time Clock Standby Mode
Organization: PAX - Public Access Unix (Adelaide)
Lines: 24
NNTP-Posting-Host: flash.pax.tpa.com.au
I am having trouble obtaining the specified standby current drain from
a MC146818A Real Time Clock.  Has anyone out there had some experience
in doing this?  The specs call for a few sequences to be met before
standby mode is activated, and are a bit hard to decipher on that, but
I thought that I had it worked out.  However, with a 32kHz crystal the
lowest current drain I can acheive at 3.7V Vcc is 150uA.  This is
three times the specified MAXIMUM under the conditions I am attempting
to create.
I have done the following things:
1) Made sure that RESET/ is asserted for Trlh after powerup, and AS is
low during this time.
2) Made sure that there is a cycle on AS after the negation of RD/ or
WR/ during which STBY/ was asserted.
What am I doing wrong?
Thanks very much,
Martin.
From: u934132@student.canberra.edu.au (Ogawa / Taro Stephen (ISE))
Subject: Help wanted
Summary: Decoders
Organization: University of Canberra
Lines: 9
Could someone please tell me if a 1/4 decoder is the same as a 1 to 4
demultiplexer. I know how to link 2 of these to get an 8 output circuit,
but how do I link 5 of these to make a 1/16 multiplexer. Sorry if this
seems like a lame question, but I'm only a newbie to electronics, and I
have to do this circuit. Please make any mail as droolproof as possible.
Thanx,
Taro Ogawa
(u934132@student.canberra.edu.au)
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: Dmm Advice Needed
Organization: Macquarie University
Lines: 30
Distribution: world
NNTP-Posting-Host: macadam.mpce.mq.edu.au
|>   What the world needs is a meter that won't let you change ranges or
|> turn it on/off with a lead stuck in the amps jack - a little bit of
|> clever plastic detailing would take care of this and make the world
|> safer for electricans, anyway.
|>    Not that I've ever put a meter on the wrong range into a live
|> circuit, no, not me...not more than a dozen times, anyway....
|>     Bill
|>
|>
|> bills@inqmind.bison.mb.ca
|> The Inquiring Mind BBS, Winnipeg, Manitoba  204 488-1607
The Fluke 87 beeps at you if you try to take it out of a current measuring
range while there is still a lead plugged in to the current sense socket.
... this should solve your problem - unless you are in a noisy environment.
JohnH
----------------------------------------------------------------------------
|  _  |_   _   |_|  _   _|  _|              Electronics Department
|_| (_) | | | |  | | (_| (_| (_| \/           School of MPCE
---------------------------------/-           Macquarie University
Sydney, AUSTRALIA 2109
Email: johnh@mpce.mq.edu.au, Ph: +61 2 805 8959, Fax: +61 2 805 8983
----------------------------------------------------------------------------
From: corwin@igc.apc.org (Corwin Nichols)
Subject: Re: Fujitsu 8" HDD
Lines: 13
Nf-ID: #R:1993Apr17.204351.2256@aber.ac.uk:-1606259317:cdp:1466200011:000:729
Nf-From: cdp.UUCP!corwin    Apr 19 08:23:00 1993
The Fujitsu 2322 uses what is known as an 'SMD' interface (Storage Module
Device?).  A lot of older minis used it.  Sun still does on their server
models.  There are several different speeds of SMD, and I think that the
Fuji drive you have is rated at about 24 Mb/sec (thats megabits).  There
used to be several companies that made couplers for the PC (Interphase in
Texas being one), but I think that the market pretty much has dried up.
Controllers for this type of drive are readily available for VME buses
though.  Rumor has it that there is a SMD to SCSI adapter available, but
I think that it was designed for slower SMD devices.  In other words,
if you have a PC or Mac, that drive is pretty much dogmeat.
Cheers,
Corwin
From: ba1634807@ntuvax.ntu.ac.sg
Subject: pwm control thru software
Lines: 17
Nntp-Posting-Host: v9001.ntu.ac.sg
Organization: Nanyang Technological University - Singapore
currently I am using the 8051 microcontroller with external eprom..
In order to drive the dc motor (with direction) I use the Pulse width modultion
thru software control(Assembly language programming). However I am afraid that
they will be overheads and thus alter the pulse timing. My question is
is the software pwm control reliable?. I understand that port 0 is a latch
and so I vary the duty cycle by setting it high first and at the desire
duty cycle then I set low..? Any improments ?
Subject: Re: Looking for Electronics Dept Info in Austrailia
From: MATGBB@LURE.LATROBE.EDU.AU (BYRNES,Graham)
Organization: La Trobe University
In-Reply-To: hjkim@hyowon.pusan.ac.kr's message of Mon, 19 Apr 93 00:38:00 GMT
X-News-Reader: VMS NEWS 1.24
Lines: 20
In <1993Apr19.003800.18288@worak.kaist.ac.kr> hjkim@hyowon.pusan.ac.kr writes:
> Hi Netters!
>
> I am looking for the list of universities in Austrailia, which has electronics department.
> I am considering to spend a year for research in Austrailia about communication area.�� I am interested in Mobile communication areas and spread spectrum communications etc.
> But I don't have any information about Austrailian Universities.
> Can anybody recommend a good university in co��mmunic��ation area?
> Any comments will be welcomed!
>
> Bye.
>
> Jaehyung Kim
>
Well, I honestly don't know if they are good, bad or indifferent, but there
is an electronics dept here at La Trobe:
La Trobe University, Bundoora VIC 3083 Australia
Fax +613 471 0524
Chairman is Prof Ian White. Sorry, don't have an email address.
Graham B
From: NWZ96H@cheltenham-he.ac.uk (NWZ96H)
Subject: Hatley & Pirbhai help...
Lines: 12
Hello,
Has anyone used the Requirements Analsys methodology Hatley & Pirbhai ? I am
a British final year real-time degree student, and as a project I am covering
this methodology. I would be very grateful to anyone who could give me their
views on this method. Please mail me if you feel you can help, and I will send
you my questions.
Thanks in advance,
David Phelps	(nwz96h@chelt.ac.uk)
From: dp@cec1.wustl.edu (David Prutchi)
Subject: OEM weight scale
Nntp-Posting-Host: cec1
Organization: Washington University, St. Louis MO
Lines: 13
Does someone sell OEM scale units with either analog or digital output?
I need something like the scales used in supermarket cash registers,
with a dynamic range of a few pounds and reasonable accuracy.
Any sources ?        -David
+------------------------------------------------------------+
|  David Prutchi                 HC1DT                       |
|  Washington University         <prutchi@mesun4.wustl.edu>  |
|  Campus Box 1185               <dp@cec1.wustl.edu>         |
|  One Brookings Drive           <prutchi@eng.tau.ac.il>     |
|  St. Louis, MO  63130-4899                                 |
+------------------------------------------------------------+
From: d2bohre@dtek.chalmers.se (Henrik Bohre)
Subject: Digital Answering mach
Keywords: digital
Nntp-Posting-Host: hacke9.dtek.chalmers.se
Organization: Chalmers University of Technology, Gothenburg Sweden
Lines: 10
Does anybody know anything about the chips D6275A/D6235A/D6205A chips from
DSP Telecommunications Inc?
I'd greatly appreciate information about price, pinouts and peripherals.
Regards,
Henrik Bohre
@>-+--
From: mvanhorn@desire.wright.edu (H.I.T. ( Hacker-In-Training ))
Subject: Re: Need to find out number to a phone
Organization:  Wright State University
Lines: 12
Since I have seen various different numbers to dial to get your number read
back to you by the phone company, could someonepost a list or point me to a
book where I could get a list of all the different numbers for the U.S.?
Failing that, could someone tell me Ohio's?
--
???????????????????????????????????????????????????????????????????????????????
?	451                             ?	I don't speak for Wright      ?
?  	mvanhorn@desire.wright.edu	?       State, I just give them       ?
?	Wright State University         ?       huge amounts of money.        ?
???????????????????????????????????????????????????????????????????????????????
From: keith@churchill.ColumbiaSC.NCR.COM (Keith.Boyd)
Subject: Re: Need to find out number to a phone line
Nntp-Posting-Host: churchill.columbiasc.ncr.com
Organization: NCR Corp., Columbia SC
Lines: 30
In article <20756.2bd16dea@ecs.umass.edu> alee@ecs.umass.edu writes:
>
>Greetings!
>
>        Situation:  I have a phone jack mounted on a wall.  I don't
>                    know the number of the line.  And I don't want
>                    to call up the operator to place a trace on it.
>
>        Question:   Is there a certain device out there that I can
>                    use to find out the number to the line?
>        Thanks for any response.
>                                                    Al
>
>
Do you get a dial tone when you plug a phone into the jack??  If not,
then the line is possibly disconnected from the nearest telco junction
box. If you do get a dial tone, then surely the telco is sending a bill
for the line to *someplace* or *somebody*. Are you sure that what you
are doing is on the level. Sounds to me like you are just trying to get
at somebody's unlisted number.  Fess up.
Keith
--
| Keith Boyd  (NCR- MCPD Cola.) |  Nothing could be finer than huntin' and   |
| 3325 Platt Springs Rd.        |    and fishin' in South Carolina! -Me-     |
| West Cola., S.C. 29170 |   Go Gamecocks!   | keith.boyd@columbiasc.NCR.COM |
| Vp: 803-791-6419 or 6455    | From uunet: uunet!ncrcom!ncrcae!clodii!keith |
From: Mike Diack <mike-d@staff.tc.umn.edu>
Subject: Re: RAMs &ROMs with ALE latches (for 8051's)
X-Xxdate: Wed, 21 Apr 93 03:04:18 GMT
Nntp-Posting-Host: dialup-slip-1-88.gw.umn.edu
Organization: persian cat & carpet co.
X-Useragent: Nuntius v1.1.1d7
Lines: 15
In article <1qg98sINNokf@sheoak.ucnv.edu.au> j. pethybridge,
jeff@redgum.ucnv.edu.au writes:
> I asked this a year ago, but i am still looking.
> I am getting sick of having to use a HC373 or a 8751/2.
Check out Xicor's new goodie in the April 12th edition of EETimes
X88C64 - an 8k * 8 E2PROM with built in latch AND bootloader setup.
You hook it directly to your '51, power it up, the prom initialises the
serial port on the '51, you load in your code via RXD, this gets blatted
onto the E2PROM, then you reset and run - i'm sure Dallas also does
something like this too, i suppose it would boil down to relative
prices, and the Dallas part freeing up P0 & P2 completely. I wonder
if ANYONE has ever managed to design a single sided PCB with an
8051, 573, EPROM, SRAM and >>NO LINKS<< ?
cheers
Mike.
From: fontana@cis.ohio-state.edu (Mark Fontana)
Subject: Homemade projector automation
Organization: The Ohio State University Dept. of Computer and Info. Science
Lines: 37
Distribution: usa
NNTP-Posting-Host: tomato.cis.ohio-state.edu
Hi all,
I'm an assistant manager at a local art theater here in Columbus.  I'd
like to expand our show automation a bit- namely add the capability to
use cue tapes to bring the houselights up.  Our current automation
consoles date from the early 60's and don't provide this function.
We already have the combo failsafe/contact rollers to read the cuetapes,
and our dimmer system will raise the houselights when its fade-up control
circuit (120 VAC) is momentarily closed, for at least 0.5 second.
I've tried wiring the dimmer control to a 12V relay, activated when the
cue tape completes the circuit.  Low tech and simple, but there's one
problem:  In order to get the 1/2 second pulse, there needs to be
a sh**load of cuetape on the film.  (35mm runs at 90 feet per minute,
so to get a 1/2 second pulse, there needs to be at least 9 inches of solid
cuetape!)
Ideally, I would like to use a single cross-cue to accomplish this function.
(A single strip of cuetape perpendicular to the length of the film)
This would give a pulse of approximately 1/100 of a second.
What I need is a circuit to detect the short cue and activate the relay
for around 1/2 second.  The ability to adjust how long the relay
is activated would be nice.  I figure this would require an RC circuit
of some sort.  I'm sure some of you already have the solution figured
out in your heads.  Any suggestions and schematics would be appreciated!
Thanks,
Mark Fontana
--
"Of all the arts, the cinema is  |  Mark A. Fontana
the most important."            |  Computer and Information Science
--V.I. Lenin  |  THE Ohio State University
From: dp@cec1.wustl.edu (David Prutchi)
Subject: Re: Cicuit Cellar Ink - Extras 4 Trade
Nntp-Posting-Host: cec1
Organization: Washington University, St. Louis MO
Lines: 32
In article <babb-190493113153@larc.sdsu.edu> babb@sciences.sdsu.edu (J. Babb) writes:
>Fellow Info-junkies,
>  I have an extra CCI #27 (Real Time Programming/Embedded Sensors &
>Storage) and an extra CCI #32 (Voice control of telescope, among other
>articles). No labels. No torn, cut-up, or missing pages.
>
>Would like to trade for CCI # 26, or CCI # 23, or CCI # 19 in same
>condition (Labels OK).
>
>I mail mine you mail yours mutual trust kinda thang OK?
>You don't actually throw them away, do you?
>
>Thanx,
>Jeff Babb
>babb@sciences.sdsu.edu
I have also been trying to complete my collection.  I have an extra CCI # 16
(Communications) and a # 12 (Applications in the Arts), both in mint
condition.
I would like to trade for (or buy) the following: # 1, 3, 22, 23, 25, 26, 30,
and 31.
Thanks      -David
+------------------------------------------------------------+
|  David Prutchi                 HC1DT                       |
|  Washington University         <prutchi@mesun4.wustl.edu>  |
|  Campus Box 1185               <dp@cec1.wustl.edu>         |
|  One Brookings Drive                                       |
|  St. Louis, MO  63130-4899                                 |
+------------------------------------------------------------+
From: kng@pt.com (Ken Gravenstede)
Subject: Decent, CHEAP 20+MHZ Scopes?
Organization: Performance Technologies, Incorporated
Lines: 12
Any info on modern 20MHZ or better dual trace scopes would be appreciated.
Should I buy a used one or a new one?  And where?
Please E-Mail.
Thanks in advance.
Ken
--
__
Ken Gravenstede, Performance Technologies Incorporated	kng@pt.com
315 Science Parkway, Rochester, New York 14620            uupsi!ptsys1!kng
From: cab@col.hp.com (Chris Best)
Subject: Re: Food Dehydrators
Organization: your service
Lines: 10
Distribution: usa
NNTP-Posting-Host: hpctdkz.col.hp.com
>   Does anybody out there have one of those food dehydrators I've been seeing
> all over late-night TV recently? I was wondering if they use forced air, heat,
> or both. If there's heat involved, anybody know what temperature they run at?
> My wife would like one and I'm not inclined to pay >$100.00 for a box, a fan
> and a heater. Seems to me you should be able to throw a dehydrator together
> for just a few bucks. Heck, the technology is only what? 1,000 years old?
----------
Yeah, but 1000 years ago, you couldn't buy it from a guy with sprayed-on hair!
From: wout@dutentb.et.tudelft.nl (Wout Serdijn)
Subject: Re: how can 0.022 uF be different from two 0.047 in series?!
Nntp-Posting-Host: duteela.et.tudelft.nl
Organization: Delft University of Technology, Dept. of Electrical Engineering
Lines: 43
In <1993Apr19.185326.9830@Princeton.EDU> mg@cs.princeton.edu (Michael Golan) writes:
>I was looking at the amps diagram for Sony 1090/2090 receivers, and I
>was amazed to find a difference between the US and Canadian model
>on the capacitor(s) that hangs off the output to the speakers:
>                         ------\/\/\----- to speaker (identical both models
>from amp ---------------|
>(idnetical both models) >
>                        <  10
>                        >
>                        |
>                       -----
>                      |     |
>        0.022        ---   ---        Canadian model only!
>     US model        ---   --- 0.047
>     and world-wide   |     |
>     model only.      |    ---        Candian model only!
>                      |    ---  0.047
>                      |     |
>                       ----------- gound
>The board itself is also identical, with room for all three caps. The
>US/Can versions is clearly indicated in both places.
>How does that make sense? 0.047/2 is 0.0235, essentially 0.022 for caps
>(there are just standard caps, no special W/type/precision).
>Please explain this
> Michael Golan
> mg@cs.princeton.edu
The only explanation I can think of is that two capacitors in series
can handle twice the output voltage. Sometimes two elco's in antiseries
(you know, positive sides facing eachother) are used to obtain a large
capacitor that can handle positive and negative voltages as well.
So there probably is no design-philosophical reason, but a production-cost
one.
Best 73's
Wouter
Subject: 68HC16 public domain software?
From: murashiea@mail.beckman.com (Ed Murashie)
Organization: DSG Development Eng Beckman Instruments Inc.
Nntp-Posting-Host: 134.217.245.87
Lines: 11
Does anyone know of an FTP site where I might find public
domain software for the Motorola 68HC16 microprocessor?
I am looking for a basic interpreter/compilier or a 'C'
compiler.  Thanks in advance.
Ed Murashie
------------------
Ed Murashie                     US Mail :  Beckman Instruments Inc.
phone: (714) 993-8895                      Diagnostic System Group
fax:   (714) 961-3759                      200 S. Kraemer Blvd  W-361
Internet: murashiea@mail.beckman.com       Brea, Ca 92621
From: aj008@cleveland.Freenet.Edu (Aaron M. Barnes)
Subject: Realistic PRO-2024 scanner for sale:was $200, sell for $150
Organization: Case Western Reserve University, Cleveland, Ohio (USA)
Lines: 45
NNTP-Posting-Host: slc10.ins.cwru.edu
Article 10886 of alt.radio.scanner:
Path: usenet.ins.cwru.edu!cleveland.Freenet.Edu!aj008
From: aj008@cleveland.Freenet.Edu (Aaron M. Barnes)
>Newsgroups: alt.radio.scanner
Subject: Realistic PRO-2024 for sale-was $200,sell for $150 obo
Date: 20 Apr 1993 16:01:28 GMT
Organization: Case Western Reserve University, Cleveland, Ohio (USA)
Lines: 26
Message-ID: <1r16oo$3du@usenet.INS.CWRU.Edu>
NNTP-Posting-Host: slc10.ins.cwru.edu
Hello.
I have a Realistic PRO-2024 scanner for sale.Here is a small desc
ription:
60 programible chanels
fully detailed backlighted digital display
headphone jack
antenna jack
removable telescoping antenna
auto search
coverage:
30-50mHz
118-174mHz
380-512mHz
It originally cost $200, but I will sell for $150.
Thank You.
--
/ /     Buchanan in `96!
/ /      Fear the goverment that fears your guns.
\ \/ /       Without the 2nd amendment, we cannot guarantee ou
\/ /        r freedoms.           aj008@cleveland.freenet.edu
--
/ /     Buchanan in `96!
/ /      Fear the goverment that fears your guns.
\ \/ /       Without the 2nd amendment, we cannot guarantee ou
\/ /        r freedoms.           aj008@cleveland.freenet.edu
From: johnr@col.hp.com (John T. Rasper)
Subject: ADCOM GTP500II IR sensor & repeater spec's?
Organization: HP Colorado Springs Division
Lines: 25
NNTP-Posting-Host: hplsdvf.col.hp.com
Does anyone know the details of the interface (5 wire din) for the
IR remote sensor & (2 wire IR repeater) for the ADCOM GTP-500II
preamp?  The ADCOM part numbers are the XR-500II, SPM-500II, and
IRA-500II.
A cursory physical examination of the pre-amp connector indicates
that the connector (5 pin din) may provide: (Viewed from connector front)
|
5     1     (pin ?) +?v @ ???mA
4   2      (pin ?) +/-?v @ ???mA
3        (pin 3) Signal Ground
(pin ?) Demodulated signal ?V-pp, ? polarity, ? mA drive
(pin ?) Signal to drive repeater LED (drives through 150ohm
resistor) ?V-pp
I assume that the repeater connectors (mini-plugs) drive the IR repeater
LED's directly.  True?
Can anyone fill in the ?'s.  Thanks.
--
John Rasper                         Hewlett-Packard COL
johnr@col.hp.com                    P.O. Box 2197
(719) 590-5895                      Colorado Springs, CO 80901-2197
From: moffatt@bnr.ca (John Thomson)
Subject: Re: What is Zero dB????
Nntp-Posting-Host: bcarhdd
Organization: Bell-Northern Research, Ottawa, Canada
X-Newsreader: TIN [version 1.1 PL6]
Lines: 33
marrevola@rediris.es wrote:
: In article <1993Apr6.132429.16154@bnr.ca>, moffatt@bnr.ca (John Thomson) writes:
: > Joseph Chiu (josephc@cco.caltech.edu) wrote:
: >
: > : And the measure of current, Amp, is actually named after both the AMP company
: > : and the Amphenol company.  Both companies revolutionized electronics by
: > : simulatenously realizing that the performance of connectors and sockets
: > : were affected by the amount of current running through the wires.
: >
: > Sorry.  The unit for current is the AMPERE which is the name of a french-man
: > named AMPERE who studied electrical current.  The term AMP is just an abbreviation
: > of it.  The company AMP came after the AMPERE unit was already in use.
: >
: > : The Ohmite company was the first to characterize resistances by numbers, thus
: > : our use of the Ohms...
: >
: > I don't know about this one, but it doesn't sound right.
: Are you (two) joking?
: Is the entire Internet flaming you (two)?
: Ahh!, now I remember that Ohmite company was the first introducing "the pink
: colored resistor", only for electronics working females ;-)
: --
: Manuel Arrevola Velasco   ||||| True e-mail: manolo@taf.fundesco.es |||||
: DoD #1033
:
Yes, I have taken a bit of flame on this one.  I must've been half asleep when
I posted a response to Joseph.
Greggo.
-----
Greg Moffatt  moffatt@bnr.ca
Bell-Northern Research Inc., Ottawa Canada
"My opinions; not BNR's"
From: philip@mentorg.com (Philip Peake)
Subject: Re: Radar detector DETECTORS?
Distribution: na
Nntp-Posting-Host: sun_shine.mentorg.com
Organization: Mentor Graphics
Keywords:
Lines: 33
In article <1993Apr20.022922.11861@julian.uwo.ca>, wlsmith@valve.heart.rri.uwo.ca (Wayne Smith) writes:
|> In article <1993Apr19.231050.2196@Rapnet.Sanders.Lockheed.Com> babb@rapnet.sanders.lockheed.com (Scott Babb) writes:
|>
|> >No restriction was placed
|> >on receiving RADAR (or, curiously, cordless phones.)  Enforcement
|> >of the Virginia law is in violation of the FCA of 1934.
|>
|> Isin't there some kind of rule (regulation, law, whatever) in some
|> juristictions that prohibit the use of *police band* recievers
|> in vehicles?  And that radar transmissions are included in the police band
|> so they get covered by the same regulation?
What do you mean by "police band" - there is no such thing.
Anyway, radar detectors work in shared bands.
If you applied your test, all of those radar operated door
openers in malls would be illegal.
One of the great problems here is that there are too many
ill-educated (read illiterate) people making too many laws
about subjects on which they are incompetent - there may well
be laws refereing to "police bands", they are almost certainly
local in scope (state or county) - created by well-meaning,
but incompetent idiots.
Unfortunaltely, laws do not have to be sensible (or even enforceable).
Lawmakers exist to pass laws - and will continue to do so, until
the day where you are faced with death for not doing X, and
amputation of all your limbs for doing X ... the choice will be yours.
Note: no smiley.
Philip
From: dclaar@cup.hp.com (Doug Claar)
Subject: Los Angeles Freeway traffic reports
Nntp-Posting-Host: hprtnyc.cup.hp.com
Organization: Hewlett-Packard
X-Newsreader: TIN [version 1.1 PL8.9]
Lines: 8
While driving through the middle of nowhere, I picked up KNBR, AM 1070,
a clear-channel station based in Los Angeles. They had an ad
claiming that they were able to get traffic flow information from
all of the thousands of traffic sensors that CalTrans has placed
under the pavement. Does CalTrans sell this info? Does KNBR have
an exclusive? What's the deal?
==Doug "Former L.A. commuter" Claar
From: wagner@mala.bc.ca (TOM WAGNER, Wizzard of old Audio/Visual Equipment........Nanaimo Campus)
Subject: Re: Suggestions  on Audio relays ???
Organization: Malaspina College
Lines: 63
In article <C5r60r.4ID@megatest.com>, alung@megatest.com (Aaron Lung) writes:
> In article <C5qsBF.IEK@ms.uky.edu> billq@ms.uky.edu (Billy Quinn) writes:
>>I built a little project using the radio shack 5vdc relays to switch
>>audio.  I got pretty bad 'clicks' when the thing switched.  I was doing
>>most of the common things one is supposed to do when using relays and
>>nothing seemed to get rid of the clicks.
>>
>>
>>My question is:
>>
>>	Is there a good relay/relay circuit that I can use for switching
>>audio, so that there will be *NO* noise of any kind on the audio lines.
>>
>>
>>I will appreciate any advice or references to advice.  Also, exact part
>>numbers/company names etc. for the relays will help!
>
> Are you switching high level signals or low level signals like pre-amp
> out level signals?  Also, are the clicks you mentioning the big
> clack that happens when it switches or are you refering to contact
> bounce?  How are you driving the relays?  TTL gate output?  Switching
> transistor?  How are the relays connected to what you are driving?
>
> Need more specifics to answer your question!! :-)
As a general rule, no relay will cleanly switch audio if you try to tranfer
the circuit with the contacts.  The noise you hear is due to the momentary
opening and closing of the path.
The noiseless way of transfering audio is to ground the circuit.  In high
impedance audio circuits a resistive "T" is constructed close to characteristic
impedance of the circuit.  Grounding the imputs (connected to the T) transfers
the audio.
In low impedance circuits transformers are usually used, and the inputs are
shorted out or grounded.  Secondaries are paralleled at the characteristic
impedance.
Sometimes if it is necessary to actually switch audio, a second contact is used
to momentarily short the circuit output for the duration of the switching time.
Telephone relays are handy, because contacts can be adjusted to "Make before
break and Vica Versa" but I haven't seen any of these for years.
Nowadys switching is done electronically with OP amps, etc.
A novel circuit I used to build was a primitive "optical isolator".. It consists
of a resistive photocell and a lamp, all packaged in a tube.  When the lamp is
off the cell is high resistance.  Turn the lamp on and the resistance lowers
passing the audio.  Once again this device in a "T" switches the audio.  Varying
the lamp resistance give a remote volume control.  Use 2 variable resisters and
you have a mixer!
Lots of luck!
--
73, Tom
================================================================================
Tom Wagner, Audio Visual Technician.  Malaspina College Nanaimo British Columbia
(604)753-3245, Loc 2230  Fax:755-8742  Callsign:VE7GDA Weapon:.45 Kentucky Rifle
Snail mail to:  Site Q4, C2.   RR#4, Nanaimo, British Columbia, Canada, V9R 5X9
I do not recyle.....   I keep everything!       (All standard disclaimers apply)
================================================================================
From: wagner@mala.bc.ca (TOM WAGNER, Wizzard of old Audio/Visual Equipment........Nanaimo Campus)
Subject: correction of last followup re relays
Organization: Malaspina College
Lines: 73
In article <1993Apr20.102756.1709@mala.bc.ca>, wagner@mala.bc.ca (TOM WAGNER, Wizzard of old Audio/Visual Equipment........Nanaimo Campus) writes:
> In article <C5r60r.4ID@megatest.com>, alung@megatest.com (Aaron Lung) writes:
>> In article <C5qsBF.IEK@ms.uky.edu> billq@ms.uky.edu (Billy Quinn) writes:
>>>I built a little project using the radio shack 5vdc relays to switch
>>>audio.  I got pretty bad 'clicks' when the thing switched.  I was doing
>>>most of the common things one is supposed to do when using relays and
>>>nothing seemed to get rid of the clicks.
>>>
>>>
>>>My question is:
>>>
>>>	Is there a good relay/relay circuit that I can use for switching
>>>audio, so that there will be *NO* noise of any kind on the audio lines.
>>>
>>>
>>>I will appreciate any advice or references to advice.  Also, exact part
>>>numbers/company names etc. for the relays will help!
>>
>> Are you switching high level signals or low level signals like pre-amp
>> out level signals?  Also, are the clicks you mentioning the big
>> clack that happens when it switches or are you refering to contact
>> bounce?  How are you driving the relays?  TTL gate output?  Switching
>> transistor?  How are the relays connected to what you are driving?
>>
>> Need more specifics to answer your question!! :-)
>
> As a general rule, no relay will cleanly switch audio if you try to tranfer
> the circuit with the contacts.  The noise you hear is due to the momentary
> opening and closing of the path.
>
> The noiseless way of transfering audio is to ground the circuit.  In high
> impedance audio circuits a resistive "T" is constructed close to characteristic
> impedance of the circuit.  Grounding the imputs (connected to the T) transfers
> the audio.
>
> In low impedance circuits transformers are usually used, and the inputs are
> shorted out or grounded.  Secondaries are paralleled at the characteristic
> impedance.
>
> Sometimes if it is necessary to actually switch audio, a second contact is used
> to momentarily short the circuit output for the duration of the switching time.
>
> Telephone relays are handy, because contacts can be adjusted to "Make before
> break and Vica Versa" but I haven't seen any of these for years.
>
> Nowadys switching is done electronically with OP amps, etc.
>
> A novel circuit I used to build was a primitive "optical isolator".. It consists
> of a resistive photocell and a lamp, all packaged in a tube.  When the lamp is
> off the cell is high resistance.  Turn the lamp on and the resistance lowers
> passing the audio.  Once again this device in a "T" switches the audio.  Varying
> the lamp resistance give a remote volume control.  Use 2 variable resisters and
> you have a mixer!
>
> Lots of luck!
> --
> 73, Tom
> ================================================================================
> Tom Wagner, Audio Visual Technician.  Malaspina College Nanaimo British Columbia
> (604)753-3245, Loc 2230  Fax:755-8742  Callsign:VE7GDA Weapon:.45 Kentucky Rifle
> Snail mail to:  Site Q4, C2.   RR#4, Nanaimo, British Columbia, Canada, V9R 5X9
>
> I do not recyle.....   I keep everything!       (All standard disclaimers apply)
> ================================================================================
--
73, Tom
================================================================================
Tom Wagner, Audio Visual Technician.  Malaspina College Nanaimo British Columbia
(604)753-3245, Loc 2230  Fax:755-8742  Callsign:VE7GDA Weapon:.45 Kentucky Rifle
Snail mail to:  Site Q4, C2.   RR#4, Nanaimo, British Columbia, Canada, V9R 5X9
I do not recyle.....   I keep everything!       (All standard disclaimers apply)
================================================================================
From: wagner@mala.bc.ca (TOM WAGNER, Wizzard of old Audio/Visual Equipment........Nanaimo Campus)
Subject: correction re Audio relay followup
Organization: Malaspina College
Lines: 12
Gremilins have attacked my keyboard and the correction to my followup on audio
relays got fouled up.
Varying lamp resistance, should read, "Varying lamp voltage"
--
73, Tom
================================================================================
Tom Wagner, Audio Visual Technician.  Malaspina College Nanaimo British Columbia
(604)753-3245, Loc 2230  Fax:755-8742  Callsign:VE7GDA Weapon:.45 Kentucky Rifle
Snail mail to:  Site Q4, C2.   RR#4, Nanaimo, British Columbia, Canada, V9R 5X9
I do not recyle.....   I keep everything!       (All standard disclaimers apply)
================================================================================
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Subject: Re: Building a UV flashlight
Nntp-Posting-Host: aisun3.ai.uga.edu
Organization: AI Programs, University of Georgia, Athens
Lines: 13
You can get a *little* UV by putting a heavy UV filter (deep purple) in
front of an ordinary flashlight bulb (the brightest you can get).
My father used a setup like this in law enforcement work circa 1964.
Good UV ("blacklight") bulbs work like fluorescent bulbs.  I'd proceed by
getting a cheap battery-powered _fluorescent_ light, then going to an
electrical supply house and finding a UV bulb that would fit it.
--
:-  Michael A. Covington, Associate Research Scientist        :    *****
:-  Artificial Intelligence Programs      mcovingt@ai.uga.edu :  *********
:-  The University of Georgia              phone 706 542-0358 :   *  *  *
:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :  ** *** **  <><
From: kehoe@netcom.com (Thomas David Kehoe)
Subject: Re: Telephone Controlled Power Bar Needed
Organization: Netcom - Online Communication Services (408 241-9760 guest)
Lines: 25
I had a similar idea, for a fax/answering machine switch,
to put both machines on one line.  You order distinctive
ringing from your phone company.  This is $3/month here.
You get a second (unpublished) phone number.  When
someone calls this number, your phone rings with short
rings instead of long rings.
You set up your answering machine on 4 rings and your fax
on six rings.  You'd give out the new # as your fax #.
A device would measure the length of rings.  When it
detects a short ring, it turns off your answering machine.
Five rings later your fax picks up the call.
This should be cheaper and more elegant than the $80
switches now available.
But that's not what I did.  I'm giving out the new
# to my friends and customers.  This should leave the
old # for telemarketers, etc.  I won't pick up the
phone when I hear the long rings.
--
"Why my thoughts are my own, when they are in, but when they are out
they are another's." - Susannah Martin, hanged for witchcraft, 1692.
Thomas David Kehoe          kehoe@netcom.com         (408) 354-5926
Organization: Penn State University
From: <PCA103@psuvm.psu.edu>
Subject: ATARI 2600 Processors
Lines: 12
Does anyone know what processor the Atari 2600 used? What I'm looking for is th
e pin-outs for the Atari 2600.... the schematics for it it... does anyone have
any idea where I could find this or any related information? This is very impor
tant. Also, are the ROM chips that were used fo rthe 2600 games still available
, or were they propreitary? Please email me with any responces, as this is very
important.. Thanks a million...
BTW- Anyone who works/has worked for Atari, I could really use your help with i
nfo on the old 2600, please email me if you are willing to help me.... thatnks
alot!!
-Peter
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: Dmm Advice Needed
Organization: Northeastern Ohio Universities College of Medicine
Lines: 19
I've had my Fluke 8060A here at work for just over 10 years now.
It is a wonderful meter.  Several colleagues here have some of the
newer Fluke meters, though I still would just as soon hang on to my
8060.  The 8060 a is the 1980s digial "analog" to the Simpson 260
analog DMM of the 1950-1960s.  There was/is (?) an 8060B that had
extended frequency response.
I've got a nifty little pen shaped meter made by Soar that I keep
in my toolbox at home.  I've had that for six or seven years now
and only replaced the batteries a couple of timees; it is more than
adequate for day-to-day hobby use.  I think Soar OEMs their stuff
for a number of vendors.  Some of JDR Microdevices' stuff looks
rather similar to Soar's.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: help: How to reduce the RPMs of a Boxer fan ?
Organization: Northeastern Ohio Universities College of Medicine
Distribution: na
Lines: 18
Yes, you increase the RPM slip of a "boxer" type fan by installing
a capacitor in series with the fan's power supply.  The air flow of
small 3.5 inch fans can be reduced by about 50% by using a 1 to 4
uF capacitor.  Use a good grade nonpolarized unit with working
voltage rating around 250 volts.  Note that some impriical study is
usually required to experimentally determine the best size
capacitor for a given application.
For DC powered applications, try the Radio Shack 12 volt box fan.
It can run and start reliably from as low as about 4.5 VDC.  It is
exceptionally quiet, but at admittedly low flow.  I wish I knew who
made the fans for Radio Shack.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: cantrell@sauron.msfc.nasa.gov (Eric Cantrell)
Subject: EEG Kit?
Nntp-Posting-Host: sauron.msfc.nasa.gov
Organization: NASA/MSFC
X-Newsreader: NN version 6.4.19
Lines: 9
Awhile back someone posted some information on where you can get
kits to build an EEG.  Does anyone remember where you could get
this.  I'm very interested in getting some info on this.  Thanks
in advance.
eric
cantrell@sauron.msfc.nasa
From: coyne@thing1.cc.utexas.edu ()
Subject: Re: Radar detector DETECTORS?
Organization: At UT? That's a joke.
Lines: 24
NNTP-Posting-Host: thing1.cc.utexas.edu
It is illegal to use anything you eavedropped on for a business
or for an illegal use.  Jurisdictions that ban radar detectors or
police monitors, are essentially making the claim that there is no
other reason for a radar detector or police radio monitor.
The results of fighting these claims in courts have been mixed.
The federal courts are not anxious to intervene and state courts
have sometimes held that the feds have exclusive jurisdiction
and sometimes they have not.  A lot of state courts do not have
enough imagination to see any use for a radar detector besides
avoiding law enforcement action for speeding.
When you buy a radar detector, amongst the guarrantees, instructions,
explanations, and other detritus, is an invitation to join an
association dedicated to preserving your right to use a radar detector.
(I promise I am not making this up!)
I do not think radar detector manufacturers would be making any
headway at all in courtrooms if police departments enforced speed
laws with a strict eye to public safety and a blind eye to the fund
raiser aspect of tickets.
Mike Coyne
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: Dayton Hamfest
Organization: Northeastern Ohio Universities College of Medicine
Distribution: usa
Lines: 33
Yes,
Take Interstate I-70 to the route 48 exit.  Go south on 48 about
2-1/2 miles.  Trun right on Shiloh Springs Road.  The hamvention is
at the Harrah arena, which is about 1 mile west and on the north
side of the Road.  Parking at the arena is limited.  Lodging is
probably entirely booked-up within a 40 mile radius.  Good luck.
|                |
48               I75
|                |
----------I70----------....---------
|                |
|                |
X     |                |
(mall)  --------|                |
S. Springs   |
It is possible to park at the mall to the west.  There are shuttle
busses running between the arena and the mall.
If possible, get a Montgomery County, OH map from your local AAA
office.  It should be free if you are an AAA member.
If you don't already have definite plans, now is not a particularly
good time to start to think about going to the hamvention.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: verity@jack.sns.com (Steve Verity)
Subject: Need help with video detection circuit
Organization: Systems'n'Software
Lines: 55
I am trying to build a circuit that detects the presence of video (Vs.
a blank screen) by monitoring the R,G, and B outputs of a graphics
card.  It should be able to detect the presence of a single pixel at
65 MHz, which would mean detecting a 15 NS pulse.  It should also be
able to tell the difference between a blank screen (about 300 mv)
and a dim screen (say, around 310 mv).  Oh yes, it also needs to be
cheap.
My first circuit was a dismal failure.  I used 3 compariators; each
compariator had the + input going to one of the guns, the - input
went to a reference created by a voltage divider(a potentiometer).
The first problem was that the compariator was way too slow.. I
needed to get several pixels in a row before it would fire the
compariators, so I could have a whole screen full of text, but my
circuit would not detect it.
The second problem is that there was more noise on the reference then
the smallest difference between a blank screen and a dim screen.  In
fact the difference between completely black and completely white is
only 650 mv.  I am wondering if I am going to have to amplify the
video signals to make this work.
There are faster compariators, but they are expensive, and require
split supplies.   I would need to replace my .49 quad compariator
with three 1.89 compariators, and create a whole new power supply
circuit.
At this point, I think what I need is some sort of transistor
circuit.  Transistors are fast and cheap and should do the trick...
Unfortunately, I am way out of my league when It comes to designing
transistor circuits, so I am appealing to the net for help.  Any
ideas, tips, circuits, pointers, references, etc. would be greatly
appreciated.
Oh yes, I only sample the output of this thing every second or so, so
I don't need a fast response time at all, however, I haven't found a
way to take advantage of that fact.
Thanks a lot for any help anybody might be able to give. Of course,
you will have my undying gratitude.
Steve Verity
--
..........>.........>........>......>...>...>..>..>..>..>.>.>.>>>>>>>>+ .
Steve Verity                  +   +             ...Maxed on MIDI        + .
+      verity@jack.sns.com      + ..   +
From: sburton@dres.dnd.ca (Stan Burton)
Subject: Long distance IR detection
Content-Type: text/plain; charset=iso-8859-1
Nntp-Posting-Host: stan
Content-Transfer-Encoding: 8bit
Organization: Defence Research Establishment Suffield
X-Newssoftware: GRn-beta 1.16g (04.01.93) by Michael B. Smith & Mike Schwartz
Mime-Version: 1.0
Lines: 19
--
I would like to be able to detect the angular position (low accuracy) of an
IR emitting source at a distance of about 100 meters (more is better) in
daylight.  The IR source could be emitting a signature; I'm leaning toward
30 KHz square wave with 50% duty cycle.
I am considering the use of a quadrant detector from Centronic Inc. to give
information to a pan/tilt head to point the sensor and thus determine the
angles.  For the source I am considering wazing the heck out of an IR LED(s),
possibly an Optek OP290 or Motorola MLED81.  Wazing would mean at least 1 Amp
current pulses.  At this current the duty cycle of the LED drops to 10% and I
would need to cycle five of them in turn to get the 50% required.
Has anyone done something like this?
Stan Burton (DND/CRAD/DRES/DTD/MSS/AGCG)                 sburton@dres.dnd.ca
(403) 544-4737     DRE Suffield, Box 4000, Medicine Hat, AB, Canada, T1A 8K6
From: drand@spinner.osf.org (Douglas S. Rand)
Subject: Re: Power, signal surges in home...
In-Reply-To: randall@informix.com's message of 19 Apr 93 20:37:19 GMT
Organization: Open Software Foundation
Lines: 76
In article <randall.735251839@woof> randall@informix.com (Randall Rhea) writes:
gstovall@crchh67.NoSubdomain.NoDomain (Greg Stovall) writes:
>Anyway, over the weekend, I was resting on the sofa (in between chores),
>and noticed that I briefly picked up what sounded like ham radio traffic
>over my stereo and television, even though both were off.  Also, all the
>touch sensitive lights in my house start going wacko, cycling through
>their four brightness states.
>I presume that some ham operator with an illegal amplifier drove past
>my house (I live on a busy thoroughfare); would this be a correct presumption?
>What kind of power must he be putting out to cause the effects?
>The affected equipment is about 100 feet from the road...
Hams are unlikely to have an illegal amp,  and are also unlikely to
have a "dirty" amp.
Hams can legally run up to 1500 watts.  It is very unlikely, however,
that a ham would be running that kind of power from a car.  Ham rigs
Not possible either.  You'd need about a 300 amp alternator for
just the amplifier.  I can just see it.  You need to slow
down on a downgrade,  so you hit the push to talk button.
for cars put out around 100 watts.  It is possible that a 100 watt
radio would cause interference to consumer electronic 100 feet
away.  Most TVs, stereos, and VCRs have very poor RF shielding.
If you experience the problem frequently, it may be
caused by a ham, CBer, or other radio operator in a base station
nearby.    The interference may have been caused by a radio
transmitter used for other purposes, such as police, fire,
etc.  If you heard voices over your stereo, I think you are
correct in assuming that the source is an RF transmitter.
If you have frequent trouble, you may want to try the RF ferrite
chokes available at Radio Shack.  The interference is probably
being picked up by your speaker wires, and those chokes can
be installed on the wires very easily (without cutting them).
Good instructions are included with the chokes.
If that does not solve the problem, you may want to search your
neighborhood for a radio operator.  Look for antennas on the roof
or car.  Talk to him/her about your problem.  There are things
a radio operator can do to reduce interference.
And please remember to be friendly when approaching your
local radio operator.  This person may or may not be the
cause of your troubles,  and you'll get better cooperation
and help if you assume that he is going to be helpful (most
are).  It was amazing the accusations that we sometimes
dealt with as I grew up.  We were blamed for skip (ghost
pictures on the TV that occur at sunspot peaks),  c.b.
interferance,  dead grass :),  you name it.
BTW, the local operator should try and help you whether or
not he or she is directly responsible.  It is part of
being a good neighbor and that is how the FCC views it.
Too bad they don't require the consumer equipment makers
to take any precautions.
Last, you can usually tell ham radio vs. CB.  Ham operators are
required to declare their call (sign) every so many minutes (no more
than 10).  So if you hear "This is WA1QT" or some other call starting
with A, W or K and no more than 6 total characters, you heard a ham.
CB'ers probably won't sign (I don't know that they're even required
to) and fire/police have other private ids.
--
Douglas S. Rand <drand@osf.org>		OSF/Motif Dev.
Snail:         11 Cambridge Center,  Cambridge,  MA  02142
Disclaimer:    I don't know if OSF agrees with me... let's vote on it.
Amateur Radio: KC1KJ
From: hl00@ns1.cc.lehigh.edu (HOU-SHENG LIN)
Subject: Laser vs Bubblejet?
Organization: Lehigh University
Lines: 12
Well, I'm not too sure if this would be the right place to post this, but
anyway, here goes:  I was just noticing that some of the current bubblejet
printers offers up to 360x360 resolution while a lot of lower end laser
printers only offer 300x300.  However, the laser printers still seems to be
significantly pricier than the bubblejets... how is this?  Or am I missing
something about the resolution thing?
--
-Sheng
hl00@pl122.eecs.lehigh.edu
hl00@m180k.cc.lehigh.edu
hl00@lehigh.edu
From: monta@image.mit.edu (Peter Monta)
Subject: Re: MC SBI mixer
In-Reply-To: musone@acsu.buffalo.edu's message of 19 Apr 93 21:10:14 GMT
Organization: MIT Advanced Television Research Program
Lines: 24
musone@acsu.buffalo.edu (Mark J. Musone) writes:
> P.S. any REALLY GOOD BOOKS on AM/FM theory ALONG WITH DETAILED
> ELECTRICAL DIAGRAMS would help a lot.
> I have seen a lot of theory books with no circuits and a lot of
> circuit books with no theory, but one without the other does not help.
Mixers have a wide variety of implementations; the Mini-Circuits
part you mention is a doubly-balanced diode mixer, but active ones
(BJT, FET) seem more popular in consumer receivers.  You might
call MCL; they have a nice catalog.
The universal answer for wide-coverage, theory+practice, RF design
is the _ARRL Handbook_, published by the American Radio Relay
League, the radio amateur organization.  Any technical bookstore
can order you one.  The book is superb, with lots of accessible
theory, construction projects, and generally interesting stuff.
You might also check out _Solid State Design for the Radio Amateur_
(I think), by Hayward and <someone>.  This has sharper design
and test information about subsystems like mixers.
Peter Monta   monta@image.mit.edu
MIT Advanced Television Research Program
From: geva@concave.cs.wits.ac.za (Geva Patz)
Subject: How do I make me own really-short-run CD's
Summary: I want a really short production run of homemade music CDs -- how?
Keywords: CD mastering pressing homebrew short-run music
Lines: 13
Organization: Wits University Electrical Engineering
I want to be able to take a bunch of home-made songs (from DAT or other
suitable master) and output them to a short run (10-20 off) of standard
music CDs. Would one of the CD recorders designed for writeable CD ROMs work
for this purpose? Alternatively, is there a service that does this sort of
thing for a fee?
I'm after as much information as possible on the alternatives (cost, lead
time, equipment required, procedure to follow, etc.)  Email replies would be
appreciated.
%%%%     Geva Patz
Geva    Department of Computer Science, WITS University
%%%%   geva@concave.cs.wits.ac.za
From: sehari@iastate.edu (Babak Sehari)
Subject: How to the disks copy protected.
Originator: sehari@marge.ecss.iastate.edu
Organization: Iowa State University of Science and Technology, Ames, Iowa.
Lines: 10
---
I was wondering, what copy protection techniques are avaliable, and how
effective are they?  Has anyone have any experience in this area?
With highest regards,
Babak   Sehari.
--
From: jung@rz.tu-ilmenau.de (Dirk Junghanns)
Subject: W86C451, W86C456 info wanted
Nntp-Posting-Host: dali.rz.tu-ilmenau.de
Reply-To: jung@rz.tu-ilmenau.de (Dirk Junghanns)
Organization: Technische Universitaet Ilmenau
Lines: 12
Does anybody have informations about the
W 86 C 451   and  W 86 C 456 chips (40pin DIL pckg)?
They are build in a multifunction io-card for pc.
Thanks
Dirk
--
------------------------------------------------------------
Dirk Junghanns                    junghanns@rz.tu-ilmenau.de
------------------------------------------------------------
From: vanderby@mprgate.mpr.ca (David Vanderbyl)
Subject: Re: Power, signal surges in home...
Nntp-Posting-Host: chip
Reply-To: vanderby@mprgate.mpr.ca (David Vanderbyl)
Organization: MPR Teltech Ltd.
Lines: 10
drand@spinner.osf.org (Douglas S. Rand) writes:
>   Hams can legally run up to 1500 watts.  It is very unlikely, however,
>   that a ham would be running that kind of power from a car.
>
>Not possible either.  You'd need about a 300 amp alternator for
>just the amplifier.
It is too possible.  As the original poster said "it is very unlikely"
but definately possible.  (Can you say batteries?)
From: rky57514@uxa.cso.uiuc.edu (Tall Cool One )
Subject: PADS Question - How do I go from a schematic -> PCB?
Organization: University of Illinois at Urbana
Lines: 17
After I have produced a schematic with PADS-LOGIC, how do I import it into
PADS-PCB to create a PCB pattern?  The only way I've gotten it to work is
to output a FutureNet netlist, and then import this into PADS-PCB.  Is there
another way of doing this?  I didn't see any information in the instructions
provided, but I might have missed something.  Any suggestions would be
greatly appreciated.  Thanks!
_I_______________________________________________________________________I_
(_@_)                                                                   (_@_)
|   |   Raymond Yeung               Internet: Nimbus@uiuc.edu           |   |
|   |                                         rky57514@uxa.cso.uiuc.edu |   |
|   |   EE student at the                                               |   |
|   |   University of Illinois    CompuServe: 70700,1011                |   |
|   |   at Urbana-Champaign                                             |   |
(___)-------------------------------------------------------------------(___)
I                                                                       I
From: ianchan@leland.Stanford.EDU (Ian Hin Yun Chan)
Subject: Need help on...
Organization: DSG, Stanford University, CA 94305, USA
Lines: 24
I need help on 4 components:
BAT85 diode
-----------
I know Digi-key or Newark sells them, but the minimum order is 25!
Does anyone know where I can get smaller orders of this diode, or
an equivalent replacement?
BC546B transistor
-----------------
Ditto for this transistor.
74HC239 chip
------------
Digi-key, Newark and Mouser do not appear to carry ths chip - does anyone
know what this does and where I can obtain it?
YM3623B chip
------------
This Yamaha chip decodes S/PDIF data (from CD or DAT). Where can I obtain
one of these?
Thanks in advance,
- Ian
From: kolstad@cae.wisc.edu (Joel Kolstad)
Subject: Re: Laser vs Bubblejet?
Organization: U of Wisconsin-Madison College of Engineering
Lines: 29
In article <1993Apr20.173742.99726@ns1.cc.lehigh.edu> hl00@ns1.cc.lehigh.edu (HOU-SHENG LIN) writes:
>Well, I'm not too sure if this would be the right place to post this, but
>anyway, here goes:  I was just noticing that some of the current bubblejet
>printers offers up to 360x360 resolution while a lot of lower end laser
>printers only offer 300x300.  However, the laser printers still seems to be
>significantly pricier than the bubblejets... how is this?  Or am I missing
>something about the resolution thing?
Bubblejets often splatter a little bit, whereas LaserJets (given half-way decent
toner, like HP's "Microfine" stuff) don't.  Both produce very good output,
but you don't have to look too closely at the two to tell that LaserJet
output is definitely superior.
On the other hand, LaserJets which haven't been maintained properly and use
the cheapest toner the owner could find often produce awful output, much
worse than a bubblejet. :-)
One other thing... there are bubblejets, and then there are BubbleJets.
There are a few bubblejets out there that produce rather mediocre output
(such as HP's dinky little BubbleJet), whereas most produce really good
looking output (such as HP's DeskJets).  IBM and Canon both produce some of
the really good style bubblejets.
---Joel Kolstad
P.S. -- If you're in the market for a portable bublejet printer, I can
highly recommend the HP Portable DeskJet, although I've heard the portable
Canons are good too (I needed PCL support, myself).  With the DeskJet
Portable, you even get an undocumented PCMCIA card slot!
From: ravin@eecg.toronto.edu (Govindan Ravindran)
Subject: decoupling caps - onboard
Organization: Department of Electrical and Computer Engineering, University of Toronto
Lines: 10
(posted for a friend)
hello there,
I would like to know if any one had any experience with having
on-board decoupling capacitors (inside a cmos chip) for the power
lines. Say I have a lot of space left im my pad limited design.
any data on the effect of oxide breakdown? any info or pointers
are appreciated.
rs
From: dp@cec1.wustl.edu (David Prutchi)
Subject: Re: EEG Kit?
Nntp-Posting-Host: cec1
Organization: Washington University, St. Louis MO
Lines: 30
In article <cantrell.735330560@sauron.msfc.nasa.gov> cantrell@sauron.msfc.nasa.gov (Eric Cantrell) writes:
>Awhile back someone posted some information on where you can get
>kits to build an EEG.  Does anyone remember where you could get
>this.  I'm very interested in getting some info on this.  Thanks
>in advance.
>
>eric
>
>cantrell@sauron.msfc.nasa
>
Contact Circuit Cellar Inc., 4 Park St. - Suite 12, Vernon, CT 06066
(203)875-2751, FAX (203)872-2204 and inquire about HAL-4 EEG Biofeedback
Brainwave Analyzer.
In addition, if you want to build your own system from board-level compo-
nents (biosignal amplifiers, analog isolators and isolated multiplexers)
you can contact The Davron Group,P.O. Box 237, Deerfield, IL  60015
FAX (708)948-9290.
- David
+------------------------------------------------------------+
|  David Prutchi                 HC1DT                       |
|  Washington University         <prutchi@mesun4.wustl.edu>  |
|  Campus Box 1185               <dp@cec1.wustl.edu>         |
|  One Brookings Drive                                       |
|  St. Louis, MO  63130-4899                                 |
+------------------------------------------------------------+
From: dp@cec1.wustl.edu (David Prutchi)
Subject: Re: Long distance IR detection
Nntp-Posting-Host: cec1
Organization: Washington University, St. Louis MO
Lines: 88
In article <1993Apr20.183416.18744@dres.dnd.ca> sburton@dres.dnd.ca (Stan Burton) writes:
>
>--
>
>I would like to be able to detect the angular position (low accuracy) of an
>IR emitting source at a distance of about 100 meters (more is better) in
>daylight.  The IR source could be emitting a signature; I'm leaning toward
>30 KHz square wave with 50% duty cycle.
>
>I am considering the use of a quadrant detector from Centronic Inc. to give
>information to a pan/tilt head to point the sensor and thus determine the
>angles.  For the source I am considering wazing the heck out of an IR LED(s),
>possibly an Optek OP290 or Motorola MLED81.  Wazing would mean at least 1 Amp
>current pulses.  At this current the duty cycle of the LED drops to 10% and I
>would need to cycle five of them in turn to get the 50% required.
>
>Has anyone done something like this?
>
>Stan Burton (DND/CRAD/DRES/DTD/MSS/AGCG)                 sburton@dres.dnd.ca
>(403) 544-4737     DRE Suffield, Box 4000, Medicine Hat, AB, Canada, T1A 8K6
A method which will directly (almost) provide you with the information that
you require is that which is commonly used for coordinate measurements of
human body landmarks (eg. the SELSPOT system by SELSPOT AB, Sweden, and the
WATSMART System ??).  These use lateral photoeffect detectors [Lindholm and
Oberg, 1974; Woltring and Marsolais, 1980] to determine the position of a
spot of light projected (using a camera lens) over its surface.  In escence,
the detector is a large photodiode with four cathodes (one on each of the
four sides of the square detector crystal) and a single anode (the back of
the crystal).  A spot of light will produce currents which are proportional
to the position of the spot on the detector's face.  Let's try some ASCII
graphics in 2-D (so the detector has two cathodes to detect linear position)
-------------------------> 1
|                       |
|                       |       |\
-----   cathode 1         |       |  \
XXXXX                     ________| +  \
XXXXX|                            |      \        -------
light >XXXXX|                            |        \_____ divider __ output
XXXXX|     |                      |        /      -------
XXXXX|-----| |--                  |      /           |
XXXXX|   + |    |         ________| -  /           1 + 2
XXXXX|         --- gnd    |       |  /
XXXXX|         \ /        |       |/
XXXXX| anode              |
XXXXX                     |
----- cathode 2           |
|                       |
|                       |
--------------------------> 2
If the dot of light from the LED is the ONLY source of light, then the position
of the projection is given by this circuit regardless of the level of illumina-
tion (the divider is used to normalize relative to total received power).  When
this circuit is used in the presence of other sources of light, then the way of
"tuning" to it is to sample for a few msec the background signal, light the LED
for an equal time and sample that signal separately.  The difference between
the two is the position of the LED.
Hamamatsu photonics sells linear and 2-D lateral photoeffect detectors, and
they also sell the required signal processing electronics.  The ready-made
systems by SELSPOT and others are NOT cheap ...
Lindholm, L.E., and K.E. Oberg, "An Optoelectronic Instrument for Remote
On-Line Movement Monitoring", Biotelemetry, 1, 94-95, 1974.
Woltring, H.J., and E.B. Marsolais, "Opto-Electronic (SELSPOT) Gait Measure-
ments in Two and Three Dimensional Space - A Preliminary Report", Bull. Pros-
thetics Research, 46-52, 1980.
Most probably this technique can provide you with a much more accurate
measurement than you need, but I think that its simplicity beats scanning
a quadrant detector with a pan/tilt system until you reach zero difference.
- David
+------------------------------------------------------------+
|  David Prutchi                 HC1DT                       |
|  Washington University         <prutchi@mesun4.wustl.edu>  |
|  Campus Box 1185               <dp@cec1.wustl.edu>         |
|  One Brookings Drive                                       |
|  St. Louis, MO  63130-4899                                 |
+------------------------------------------------------------+
From: kushmer@bnlux1.bnl.gov (christopher kushmerick)
Subject: infra red position encoders
Organization: Brookhaven National Laboratory
Distribution: na
Lines: 16
I am looking for information on infra red based position encoders.
The idea would be to bounce the infrared source off a wall and the device would
read out the distance.
preferable it would be rs-232 addressable.
Any leads?
--
Chris Kushmerick
kushmer@bnlux1.bnl.gov
--I found my niche in life, I just didn't fit in.
From: pierson@cimill.enet.dec.com (Dave Pierson)
Subject: Re: Swr Meter For Cb Radios
Organization: Digital Equipment Corporation
Lines: 31
Nntp-Posting-Host: cimill
In article <734953838.AA00508@insane.apana.org.au>,
peter.m@insane.apana.org.au (Peter Tryndoch) writes...
>AllThe Devil ReincarnateSWR meter for CB radios
>
>TD>From: ssave@ole.cdac.com (The Devil Reincarnate)
>TD>Organization: CDAC, WA
>TD>What
>TD>is a good choice for a CB? 1/4 or 1/8 wave?
>TD>  I read the installation instructions on a 1/4 wave antenna,
>TD>and they suggested that I use an SWR to tune it at channel 12
>TD>and channel 32 for a minimum reading.  Question is, why channel
>TD>12 and 32?
>The best antenna is one that will let out the most wave (probably not the
>best explanation, but the rest makes sense) A one wave will cancell itself
>out (BTW no such beastie).
Yes there is.  Not common for CB.  The pattern is different (sort of
a cloverleaf, with four main lobes.
> The best is a 1/2 wave antenna, followed by 1/4, then 1/8 etc.
Use of anything under 1/4 wave for transmitting is very uncommon.  (The
usual "rubber duck" uses a coil to fool itself into looking like a
quarter wave.
I reccomend the ARRL Antenna Handbook, or a good basic book.
thanks
dave pierson			|the facts, as accurately as i can manage,
Digital Equipment Corporation	|the opinions, my own.
40 Old Bolton Rd		|I am the NRA
Stow, Mass 01775 USA		|pierson@msd26.enet.dec.com
"He has read everything, and, to his credit, written nothing."  A J Raffles
From: chin@ee.ualberta.ca (Jing Chin)
Subject: Need Info on DSP project
Summary: General info on building a DSP project that can manipulate music
Keywords: DSP , D/A , A/D , music , project
Nntp-Posting-Host: bode.ee.ualberta.ca
Organization: University Of Alberta, Edmonton Canada
Lines: 10
I want to start a DSP project that can maniplate music in a stereo cassette.
Is that any chip set, development kit and/or compiler that
can equilize/mix music?  Ideally, The system should have D/A A/D converters &
a DSP compiler.  A rough estimate of the cost is greately appreciated.
Thanks in advance.
Regards,
Jing Chin
e-mail address:chin@bode.ee.ualberta.ca
From: gray@feline.uucp (Kelly Gray)
Subject: Re: Pinout needed for TIL311
Organization: Humber College Technology Dept.
Lines: 29
According to my TI databook, the pinouts for the TIL311 display are as
follows:
Pin 1 - LED supply voltage
Pin 2 - Latch data input B
Pin 3 - Latch data input A
Pin 4 - Left decimal point cathode
Pin 5 - Latch strobe input
Pin 6 - Omitted
Pin 7 - Common ground
Pin 8 - Blanking input
Pin 9 - Omitted
Pin 10 - Right decimal point cathode
Pin 11 - Omitted
Pin 12 - Latch data input D
Pin 13 - Latch data input C
Pin 14 - Logic supply voltage, Vcc
The logic supply voltage is 5V @ 60-90mA. The LED supply is also 5V, but
it need not be particularly well regulated. The LED drivers on the chip
use a constant current source, so LED intensity is not affected by the
supply voltage.
--
<o_o>    Kelly Gray
gray@feline.uucp (preferred)
gray@admin.humberc.on.ca
From: mblock@reed.edu (Matt Block)
Subject: Re: How to the disks copy protected.
Article-I.D.: reed.1993Apr20.230749.12821
Organization: Reed College, Portland, Oregon
Lines: 36
In article <sehari.735331566@marge.ecss.iastate.edu> sehari@iastate.edu (Babak Sehari) writes:
>---
>
>I was wondering, what copy protection techniques are avaliable, and how
>effective are they?  Has anyone have any experience in this area?
>
>                      With highest regards,
>                           Babak   Sehari.
Uh oh...
Umm, there are a number of copy protection schemes.  Some involve
modifying the physical media, and some involve encryption schemes, &c.
All of the ones that have existed over the course of computing have
been successful for a time.  I recall, however, near monthly releases of new
ways to "crack" the copy protection scheme of the latest releases.  The fact
is, none of them are completely secure, or anywhere near it.  Some are more or
less difficult to crack, and some have already been cracked.
I guess what I am saying is that your question is difficult, if not
impossible, to answer.  What exactly do you want to know?  Do you need a good
one for a project you are working on?  How secure must it be?  Are you trying
to crack one that someone else has used?  I can probably make suggestions,
assuming the activity is strictly legal.  (In general, it is a BAD idea,
legally, to tamper with copy protection.  It can also lead to corruption of
files which you necessarily do not have back ups of (being as they are copy
protected,) which can be devestating.)  Do you have absolutely no ideas for
practical applications, and are merely curious?
Please clear up those questions, and I'll try to help as much as I
can.
Incidentally, the "Uh oh..." at the top is indicative of the dread
anyone who has watched their friends hacking equipment be carted off feels
when they are asked how to hack.  The area you are broaching is wrought with
dangers, many of which include breaking the law, or at least addressing it
(from one side or the other.)
Matt
From: moselecw@elec.canterbury.ac.nz (moz [chris moseley])
Subject: Re: Building a UV flashlight
Nntp-Posting-Host: betelgeux.canterbury.ac.nz
Organization: Electrical Engineering, University of Canterbury, New Zealand
Lines: 23
jhawk@panix.com (John Hawkinson) writes:
> My main question is the bulb: where can I get UV bulbs? Do they
> need a lot of power? etc., etc.
he ones I have seen are all fluorescent tubes. Maybe you could find a
small tube to go in one of those hand-held fluoro lanterns?
> One other thing: a friend of mine mentioned something about near-UV
> light being cheaper to get at than actual UV light. Does anyone
> know what he was referring to?
Blue lights. Ultra-violet (by definition?) goes from the blue end of the
spectrum that people see to the radio spectrum (X-rays, cosmic rays etc).
possibly you could get light at the fringe of visibility (which people
with false eye-lenses can see easily, since it's your lenses that soak up
most of the UV), however since most people use UV to get other things
to `glow', and the near-blue is less energetic, it would probably not
work as well, if it worked at all. (lecture on basic atomic physics
fits in here, about electron transitions (quantum leaps) and stuff.
moz
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Subject: Re: Power, signal surges in home...
Organization: NASA Langley Research Center and Reptile Farm
Lines: 41
NNTP-Posting-Host: grissom.larc.nasa.gov
In article <DRAND.93Apr20150701@spinner.osf.org> drand@spinner.osf.org (Douglas S. Rand) writes:
>In article <randall.735251839@woof> randall@informix.com (Randall Rhea) writes:
>
>   Hams can legally run up to 1500 watts.  It is very unlikely, however,
>   that a ham would be running that kind of power from a car.  Ham rigs
>
>Not possible either.  You'd need about a 300 amp alternator for
>just the amplifier.  I can just see it.  You need to slow
>down on a downgrade,  so you hit the push to talk button.
Now, that indeed is possible.  A good friend of mine is running about 1 KW
PeP from his car.  Yes, he does have a second alternator.  Yes, he calls
the rig an "electronic brake" since the engine noticeably slows when the
key is down.
My car, unfortunately, has so much computer junk under the hood that it's
astonishingly sensitive to RFI.  If I key a 2W HT over the engine with
the hood open, the car loses timing due to the RF leaking into the
distributor pickup.  Very poor design.
I will, however, point out that ham radio operators are usually quite willing
to help when interference is detected.  Remember that any interference is
wasted power; if I put out 1W in the TV band, that's 1W that I am not putting
out in the band I am trying to transmit on, and 1W can often be the difference
between a nice card hanging on the wall, and nothing.  CBers, however, are
usually not as helpful.  Most illegal CBers, however, will stop operation
when you inform them of a problem.  The rest of them will stop operation when
you inform the local FCC office of the problem (in writing, and giving details
and addresses).
>Last, you can usually tell ham radio vs. CB.  Ham operators are
>required to declare their call (sign) every so many minutes (no more
>than 10).  So if you hear "This is WA1QT" or some other call starting
>with A, W or K and no more than 6 total characters, you heard a ham.
>CB'ers probably won't sign (I don't know that they're even required
>to) and fire/police have other private ids.
Good advice.  Hams will frequently give their call, and will never use
a "handle."  They are less apt to use immense amounts of profanity as well,
but that's not to say that they don't from time to time.
--scott
From: avm1993@sigma.tamu.edu (MAMISHEV, ALEXANDER VALENTINO)
Subject: digital voltmeter - how does it work?
Organization: Texas A&M University, Academic Computing Services
Lines: 34
Distribution: world
NNTP-Posting-Host: sigma.tamu.edu
News-Software: VAX/VMS VNEWS 1.41
Hello,
Let me introduce a problem:
When I measure a sinusoidal wave (voltage) with a digital voltmeter, using
AC mode, my output is an rms value (a peak value over 2 squared). / Right? /
When I measure a square wave in the same mode (AC), my output is equal
to a peak value, actually, to the upper flat boundary of the wave.
I assumed, that a digital voltmeter makes some kind of integration of the
input value, and divides it over the wave period. / Right?/
Now, I used it to measure the same  square wave as above, but distorted
by high-frequency harmonics. Ideally, output should be the same, but...
The output value was only about 10% of the previous one!
Why? What is the nature of this output value? What does the voltmeter
actually measure? And what does it show?
Related question (less important to me):
What are advantages and disadvantages of digital voltmeters to compare with
analog ones?
Thank you for your attention, you could mail me your opinion at
avm1993@zeus.tamu.edu or open a discussion here. I would appreciate either
way.
Alexander V. Mamishev
____________________________________________________________________________
Power System Automation Laboratory    <>   phone office (409) 845-4623
Department of Electrical Engineering  <>   phone home   (409) 846-5850
Texas A&M University                  <>   fax   (409) 862-2282
College Station, TX 77843, USA        <>   Internet: avm1993@zeus.tamu.edu
----------------------------------------------------------------------------
From: f92anha@fy.chalmers.se (Anders Hammarquist)
Subject: Re: Need to find out number to a phone line
Organization: Chalmers University of Technology
Lines: 11
In article <23321@mindlink.bc.ca> Sean_Oliver@mindlink.bc.ca (Sean Oliver) writes:
>> Joseph Mich Krzeszewsk writes:
>>         890 the phone company will read the number of the phone you are on
>
>Where I live, I use BCTEL. The number to dial is 211 for the same result.
>
In NY City, the number to dial is 958... It seems to be different in different
areas.
Anders
From: gunnarh@dhhalden.no (GUNNAR HORRIGMO)
Subject: Re: How to the disks copy protected.
Lines: 25
Nntp-Posting-Host: pc109
Organization: Ostfold College
In article <sehari.735331566@marge.ecss.iastate.edu> sehari@iastate.edu (Babak Sehari) writes:
>I was wondering, what copy protection techniques are avaliable, and how
>effective are they?  Has anyone have any experience in this area?
>
>                      With highest regards,
>                           Babak   Sehari.
One of the easiest, and really very used ways of copyprotection, is to mark
a specific sector on the installation disk bad. This is very easy to get
around, though, if you have any knowledge of hw-hacking, but most 'normal'
users (yes those lowly key-punchers) don't. Whatever you do, please do
_not_ use a hardware key. These were very popular a few years ago, and they
STINK!!
MAIL-mail: gunnarh@sofus.dhhalden.no    SNAIL-mail: Gunnar Horrigmo
gunnarh@fenris.dhhalden.no               Oskleiva 17
N-1772 Norway
----------------------------------------------------------------------
Disclaimer: The above posting may seem like insignificant rubbish at
first glance, but if you read between the lines, you will be
surprised to discover the annals of Burt Bacharach, world peace,
Oxford Advanced Readers Dictionary, quantum physics made easy, and an
easy-to-use step-by-step walkthrough on how to make a time travelling
device that actually works.
From: edhall@rand.org (Ed Hall)
Subject: Re: Building a UV flashlight
Organization: RAND
Lines: 26
Nntp-Posting-Host: ives.rand.org
In article <C5r6Lz.n25@panix.com> jhawk@panix.com (John Hawkinson) writes:
>One other thing: a friend of mine mentioned something about near-UV
>light being cheaper to get at than actual UV light. Does anyone
>know what he was referring to?
I don't want to get into a semantic argument, but contrary to some other
postings "near UV light" /is/ "actual UV light."  The "near" means that
it is close to the visible spectrum (i.e. of relatively long wavelength),
not that it is "nearly UV."  (I'm sure you can figure out now just what
"far UV" is.)
Regular incandenscent flashlight bulbs emit tiny amounts of UV in the
near end of the spectrum, such that a filter can be used to remove the
visible light and thus create a weak UV source.  Stronger sources are
going to require gas (probably mercury vapor) discharge tubes (such as
fluorescent tubes with UV phosphor).  Be careful, though; strong UV
sources can cause physiological damage, especially to the eyes.  The
shorter wavelengths are the most dangerous.
It wouldn't project a beam like a flashlight, but replacing the tubes
in a portable fluorescent lantern with UV tubes would be a relatively
cheap way to create a portable source.  It would be bright enough to
be useful, but not dangerously so.
-Ed Hall
edhall@rand.org
From: vanderby@mprgate.mpr.ca (David Vanderbyl)
Subject: Re: Power, signal surges in home...
Nntp-Posting-Host: chip
Reply-To: vanderby@mprgate.mpr.ca (David Vanderbyl)
Organization: MPR Teltech Ltd.
Lines: 15
kludge@grissom.larc.nasa.gov (Scott Dorsey) writes:
>My car, unfortunately, has so much computer junk under the hood that it's
>astonishingly sensitive to RFI.  If I key a 2W HT over the engine with
>the hood open, the car loses timing due to the RF leaking into the
>distributor pickup.  Very poor design.
There was a news article a little while ago reporting a type of car (was
it a Volvo?) was found to stall if you used a certain brand/model of cellular
phone in it.  I seem to remember the car was recalled to fix the problem.
Hmmmmm... this has possibilities:
If the police are in pursuit of a vehicle, maybe they can bombard it with
high energy RFI.  :-)
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: Help wanted
Organization: Macquarie University
Lines: 54
Distribution: world
NNTP-Posting-Host: macadam.mpce.mq.edu.au
In article <1993Apr20.071549.24839@csc.canberra.edu.au>, u934132@student.canberra.edu.au (Ogawa / Taro Stephen (ISE)) writes:
|> Could someone please tell me if a 1/4 decoder is the same as a 1 to 4
|> demultiplexer. I know how to link 2 of these to get an 8 output circuit,
|> but how do I link 5 of these to make a 1/16 multiplexer. Sorry if this
|> seems like a lame question, but I'm only a newbie to electronics, and I
|> have to do this circuit. Please make any mail as droolproof as possible.
|>
|> 				 Thanx,
|> 					Taro Ogawa
|> 					(u934132@student.canberra.edu.au)
A 1 of 4 decoder need not be the same as a 1 to 4 demultiplexer, although
many commercial SSI implementations allow you to use one as such. Strictly,
a 1 of 4 decoder need only take two lines in and make one output change
state, according to the inputs.
A demux, on the other hand, uses two control inputs to determine which
of four outputs will reflect the state of the input signal. So there are
three inputs required.
A decoder can be used as a demux if it is equipped with an output enable
input, since this can be used as the data input (e.g. when high, all
outputs are high; when low, only the selected (by control inputs) output
will be low).
An eight way decoder is created by using the high order bit (bit 2) to
select which of two four way demuxes is enabled. Thus you achieve your
aim of having only one output of eight reflecting the input bits. Note
that this method cannot be used to create a true eight way demux, since
you have no data input (the enable line on a four way decoder) left
once you commit the enable lines to their intended purpose.
A sixteen way decoder obviously requires four, four-way decoders, plus
a mechanism to enable only one of the four at a time. Therefore, use
the fifth decoder, attached to the two high order bits, to provide the
four enable lines.
Of course, the two low order bits must be connected in parallel to the
four final stage decoders.
Please give me the credit when you submit your homework.
JohnH
----------------------------------------------------------------------------
|  _  |_   _   |_|  _   _|  _|              Electronics Department
|_| (_) | | | |  | | (_| (_| (_| \/           School of MPCE
---------------------------------/-           Macquarie University
Sydney, AUSTRALIA 2109
Email: johnh@mpce.mq.edu.au, Ph: +61 2 805 8959, Fax: +61 2 805 8983
----------------------------------------------------------------------------
From: baden@inqmind.bison.mb.ca (Baden de Bari)
Subject: *]] MOSFET help...
Organization: The Inquiring Mind BBS  1 204 488-1607
Lines: 28
Since I'm not all too keen on this area of hooking them up, I'm
asking for help.  I know better than to hook a 12v, 1a stepper line to
one, unless it can take it; however what about if I've got a 24-60v
stepper.  What sort of curent limmiting circuitry would be involved (a
small schematic would probably be helpfull).
Also, I've looked into the TIPC2701N by TI, and I was wondering
if I should use the same suggested (by you replying to this message)
current limiting circuitry on each of the 7 mosfets in the package as
that illustrated in the schematic (which you the replyer would hopefully
help me with).
... hmm... different request...
Thanks.
_________________________________________________
Inspiration  |   ___                             |
comes to     |  \   o  baden@sys6626.bison.mb.ca |
those who    | (  ^  ) baden@inqmind.bison.mb.ca |
seek the     |   /-\      =] Baden de Bari [=    |
unknown.     |                                   |
-------------------------------------------------
baden@inqmind.bison.mb.ca
The Inquiring Mind BBS, Winnipeg, Manitoba  204 488-1607
From: whit@carson.u.washington.edu (John Whitmore)
Subject: Re: minimal boolean circuit
Article-I.D.: shelley.1r2717INNdjh
Distribution: usa
Organization: University of Washington, Seattle
Lines: 41
NNTP-Posting-Host: carson.u.washington.edu
In article <1993Apr9.041505.8593@ringer.cs.utsa.edu> djimenez@ringer.cs.utsa.edu (Daniel Jimenez) writes:
>Suppose we have a boolean function which is a minimal sum-of-products
>(derived from a K-map or something), like this:
>f(a,b,c,d) = bc'd' + acd' + abc' + ab'c
>
>The books on logic design I have consulted all seem to imply that this
>is where the analysis ends  ...  But by factoring out the
>`a' term in the function, we can get fewer gates:
>f(a,b,c,d) = bc'd' + a(cd' + bc' + b'c),
>which yields 9 gates.
Yes, but... the minimization of gates is important in part
because of TIMING considerations.  A TTL gate has the basic structure
of AND/OR/INVERT, and an inversion of a sum of a product is just
exactly ONE gate delay.  The reason to find a minimal sum of products
is that this matches a hardware optimization.
A positive-OR gate (such as the 9-gate solution uses) has
TWO gate delays (and there's another gate delay in the second term)
so that the second solution, while simpler in logic symbols, can
be expected to be something less than optimal in the real world.
ECL is similar to TTL, in that it can support an OR/AND
gate with the minimum delay (unlike TTL, you get both true and
inverse outputs for 'free' when using ECL).
PALs are basically large programmable AND/OR/INVERT
gates (with your choice of internal connections between the
various sections, and perhaps some latches), so a minimum sum
of products ALSO is a way to shoehorn a logic design into
a few PALs.  It's not comparably easy to design with a minimization
of logic gates, but some software packages claim to allow you to
do so, and will take just about any mess of gates (as a nodelist
with 74xxx series logic ICs) and produce a description of
a logic cell array to do the same job.  Xilinx's XACT software
does this by treating each logic block as a macro, and expanding
it all out, then simplifying.
John Whitmore
From: blockley@csu.murdoch.edu.au (Adrian Blockley)
Subject: integrated cct-type UM82C452L manufac by UMC.
Lines: 15
NNTP-Posting-Host: essun1.murdoch.edu.au
where can I buy 1 or 2 of these chips (pref in Australia)?
What is name and address of `UMC'?
Dan
--
----------------------------------------------------------------------
Adrian Blockley                    ! I may say something profound
Environmental science              ! here one day.
Murdoch University                 !
Western Australia, 6153            !
blockley@essun1.murdoch.edu.au     !
phone 09-360 2737                  !
----------------------------------------------------------------------
From: jeff@nsr.hp.com (Jeff Gruszynski)
Subject: Re: digital voltmeter - how does it work?
Organization: Hewlett-Packard
Lines: 66
Distribution: world
NNTP-Posting-Host: hpmvd069.nsr.hp.com
X-Newsreader: TIN [version 1.1.2 PL7]
MAMISHEV, ALEXANDER VALENTINO (avm1993@sigma.tamu.edu) wrote:
:      Hello,
:
:    Let me introduce a problem:
:
:    When I measure a sinusoidal wave (voltage) with a digital voltmeter, using
: AC mode, my output is an rms value (a peak value over 2 squared). / Right? /
:    When I measure a square wave in the same mode (AC), my output is equal
: to a peak value, actually, to the upper flat boundary of the wave.
:    I assumed, that a digital voltmeter makes some kind of integration of the
: input value, and divides it over the wave period. / Right?/
:    Now, I used it to measure the same  square wave as above, but distorted
: by high-frequency harmonics. Ideally, output should be the same, but...
: The output value was only about 10% of the previous one!
:    Why? What is the nature of this output value? What does the voltmeter
: actually measure? And what does it show?
Re: RMS readings
Unless the DVM *says* it's measuring RMS, it's probably Average voltage.
The input is diode rectified and measured as DC.  If it says it's RMS
and but measures square/triangle/etc.  incorrectly, it's measuring
average and multipling by a correction that's *only* true for sine waves
(i.e.  Vave*(0.707/0.63) = Vrms).  If you want correct RMS for (most)
any waveform, you need a "True-RMS" DVM/DMM which literally does the
Root-Mean-Square calculation in either analog or digital circuitry.
:
:    Related question (less important to me):
:    What are advantages and disadvantages of digital voltmeters to compare with
: analog ones?
The last significant advantage of analog (IMO) ** was ** being able to
"see" the signal if it was changing over time (e.g.  checking
electrolytic capacitors).
Anymore, most DMM have bargraphs, etc. that duplicate this.
:
:    Thank you for your attention, you could mail me your opinion at
: avm1993@zeus.tamu.edu or open a discussion here. I would appreciate either
: way.
:
:
: Alexander V. Mamishev
:
: ____________________________________________________________________________
: Power System Automation Laboratory    <>   phone office (409) 845-4623
: Department of Electrical Engineering  <>   phone home   (409) 846-5850
: Texas A&M University                  <>   fax   (409) 862-2282
: College Station, TX 77843, USA        <>   Internet: avm1993@zeus.tamu.edu
: ----------------------------------------------------------------------------
:
--
================================================================================
Jeff Gruszynski
Semiconductor Test Equipment
Systems Engineer
Hewlett-Packard
================================================================================
(415) or T 694-3381
jeff@hpmvd061.nsr.hp.com
jeff@hpuplca.nsr.hp.com
================================================================================
From: dnewman@lynx.dac.northeastern.edu (David F. Newman)
Subject: arcade style buttons and joysticks
Organization: Division of Academic Computing, Northeastern University, Boston, MA. 02115 USA
Lines: 8
Hi there,
Can anyone tell me where it is possible to purchase controls found
on most arcade style games.  Many projects I am working on would
be greatly augmented if I could implement them.  Thanx in advance.
-Dave
dnewman@lynx.dac.northeastern.edu
From: elliott@optilink.COM (Paul Elliott)
Subject: Re: Analog switches/Balanced Demodulators
Distribution: na
Organization: DSC/Optilink Access Products
Lines: 53
In article <msf.734832494@skaro> msf@skaro.as.arizona.edu (Michael Fulbright) writes:
>I am trying to build a synchronous demodulator and I've hit a snag.
>In my application I want to be able to change the gain of an
>op amp amplifier from 1 to -1, controlable via a digital input.
>The most obvious way I've come up with is to use analog switches
>to adjust the gain of the op amp. The only analog switch I have
>experience with it the 4066. Unfortunately I want to switch an
>AC signal which goes from about -5V to 5V, and the 4066 is only
>for positive signals.
>[...]
> I have a carrier signal which varies between 0V and +5V. I want
>to demodulate an input signal by feeding the input signal thru a
>amp with a gain of 1 when the carrier is at +5V, and thru a amp
>with a gain of -1 when the carrier is 0V. The output is then
>low pass filtered. I believe this is called lock in detection as well
>as synchronous demodulation.
Look at the 4053.  This is a triple 2-to-1 transmission-gate analog
multiplexer, with positive and negative power supplies (can be run
from a single-ended supply as well).  With dual supplies, the logic
inputs still range from ground (0 Volts) to VDD.
This is a neat (well, I think so) design for a switchable-polarity
amplifier:
+-----/\/\/\-------+
|                  |
|    /--------\    |
INPUT -+-/\/\/\--+----| -      |    |
|              |  opamp |----+------- OUTPUT
+-/\/\/\--+----| +      |
|    \--------/
|
CONTROL	---------X (analog switch)
|
|
---
GND
All resistors are equal-value.  When the analog switch is closed,
the amp is inverting-gain-of-one.  With the switch open, it is
non-inverting-gain-of-one.  You can clean up the circuit to trim
out input offset current if this hurts the balance (this would show
up as carrier feed-through).
For high frequencies, the slew-rate of the opamp might cause problems,
especially if it isn't symmetrical (and it usually isn't).
--
--------     Paul Elliott - DSC Optilink - Petaluma, CA USA      ----------
{uunet,pyramid,tekbspa}!optilink!elliott -or- elliott@optilink.com
"I used to think I was indecisive, but now I'm not so sure."
From: rogerw@world.std.com (Roger A Williams)
Subject: Re: 68HC16 public domain software?
Organization: The World Public Access UNIX, Brookline, MA
Lines: 1
Doesn't Motorola AMCU have something on the BBS yet? (512-891-3733)
From: sehari@iastate.edu (Babak Sehari)
Subject: Re: How to the disks copy protected.
Originator: sehari@du139-213.cc.iastate.edu
Organization: Iowa State University of Science and Technology, Ames, Iowa.
Lines: 55
In <1993Apr20.230749.12821@reed.edu> mblock@reed.edu (Matt Block) writes:
>In article <sehari.735331566@marge.ecss.iastate.edu> sehari@iastate.edu (Babak Sehari) writes:
>>---
>>
>>I was wondering, what copy protection techniques are avaliable, and how
>>effective are they?  Has anyone have any experience in this area?
>>
>>                      With highest regards,
>>                           Babak   Sehari.
>	Uh oh...
>	Umm, there are a number of copy protection schemes.  Some involve
>modifying the physical media, and some involve encryption schemes, &c.
>	All of the ones that have existed over the course of computing have
>been successful for a time.  I recall, however, near monthly releases of new
>ways to "crack" the copy protection scheme of the latest releases.  The fact
>is, none of them are completely secure, or anywhere near it.  Some are more or
>less difficult to crack, and some have already been cracked.
>	I guess what I am saying is that your question is difficult, if not
>impossible, to answer.  What exactly do you want to know?  Do you need a good
>one for a project you are working on?  How secure must it be?  Are you trying
>to crack one that someone else has used?  I can probably make suggestions,
>assuming the activity is strictly legal.  (In general, it is a BAD idea,
>legally, to tamper with copy protection.  It can also lead to corruption of
>files which you necessarily do not have back ups of (being as they are copy
>protected,) which can be devestating.)  Do you have absolutely no ideas for
>practical applications, and are merely curious?
>	Please clear up those questions, and I'll try to help as much as I
>can.
>	Incidentally, the "Uh oh..." at the top is indicative of the dread
>anyone who has watched their friends hacking equipment be carted off feels
>when they are asked how to hack.  The area you are broaching is wrought with
>dangers, many of which include breaking the law, or at least addressing it
>(from one side or the other.)
>Matt
I have written a program and I want to market it.  I would like certain degree
of protection, since my main custmers are individuals and not the
cooperations.   I know laser hole burning method, and hardware key method,
however, my  software is going to cost only $15.00, so I can not afford that.
Also, at this low price I can not afford people make too many copy of my
software. Well, I guess say upto %20 illigal copying is ok by me.
However, I do not want someone to get a copy of PCTools and copy my software.
Off course, I never meant to forbid the true hackers from copying, since they
can develope a better program anyway.
With highest regards,
Babak   Sehari.
--
From: patter@dasher.cc.bellcore.com (patterson,george r)
Subject: Re: Power, signal surges in home...
Organization: Bellcore, Livingston, NJ
Lines: 20
In article <1993Apr20.232804.24632@mprgate.mpr.ca> vanderby@mprgate.mpr.ca (David Vanderbyl) writes:
>kludge@grissom.larc.nasa.gov (Scott Dorsey) writes:
>
>>My car, unfortunately, has so much computer junk under the hood that it's
>>astonishingly sensitive to RFI.
>
>Hmmmmm... this has possibilities:
>If the police are in pursuit of a vehicle, maybe they can bombard it with
>high energy RFI.  :-)
Right. So all the cops will be buying antique muscle cars for chase cars;
otherwise the *police* cars will die too!
-----------------------------------------------------------------------
| To get the attention of a large animal, be it an
| elephant or a bureaucracy, it helps to know what
George Patterson -  | part of it feels pain. Be very sure, though, that
| you want its full attention.
|                            Kelvin Throop
-----------------------------------------------------------------------
From: dale@access.digex.com (Dale Farmer)
Subject: Re: Building a UV flashlight
Organization: Express Access Online Communications, Greenbelt, MD USA
Lines: 31
NNTP-Posting-Host: access.digex.net
X-Newsreader: TIN [version 1.1 PL8]
John Hawkinson (jhawk@panix.com) wrote:
: Yes, I know it sounds crazy. Call it an urge. Call it what you want.
: Just don't ask why :-)
: Anyway, I'd like to build a UV flashlight, cheaply. "flashlight" means
: it should be reasonably portable, but could have a power pack if
: necessary.
: My main question is the bulb: where can I get UV bulbs? Do they
: need a lot of power? etc., etc.
: I'm not too concerned with whether it's long-wave or short-wave
: (but hey, if anyone has a cheap source of bulbs, I'll take both).
Check out a medical supply catalog, the thing you are looking for
is called a woods lamp (so you can check for woods sign, certain skin
conditions flourecse (sp) under UV light)  They come in disposable
penlight like types and larger ac powered types.  It is also used in eye
examinations, a flourescent dye is introduced to the surface of the eye,
then UV is shined on it, shows up scratches and abrasions very clearly
that would otherwise be very difficult to detect.  (for the completest the
dye is called flouescien, and in normal light appears orangish, and leaves
a mild burning sensation to the eye for 10-15 minutes, until the tears
flush it all out.
Have fun.
--Dale Farmer
From: umlangston@msuvx1.memst.edu (Mark C. Langston)
Subject: _negative_ logic high?
Summary: help!!!
Distribution: world
Organization: Memphis State University
Lines: 28
This may sound like a simple-minded question, but this is the first time
I've ever had a need for this:
I've been designing some relatively simple chip circuits based on things
like photoresistors (you know, no light to photoresistor, emit a logic
high, etc.).
Anyway, I've got some servos lying around, and I wanted to do some things
with them using digital logic.  I know all about having to pulse the signal
and everything, I just have one problem:  I'm assuming I need a negative
(yes, negative) logic high to get the thing to turn in the direction
opposite the direction it would turn under normal logic high.
Is a negative logic high (I've seen this in schematics) the same thing as
an active low, or what?  I'm not using a bi-polar power source, so how
would I get a negative logic high out of this thing?  I need to have all
three signals available:  Logic high, logic low, and negative logic high.
Any help would be greatly appreciated.  Also, please reply via email, as I
never seem to have time to read this (or any other) group lately.
Thanks much,
-mark
umlangston@memstvx1.memst.edu
From: randyd@csd4.csd.uwm.edu (Randall Elton Ding)
Subject: Re: ADCOM GTP500II IR sensor & repeater spec's?
Organization: Computing Services Division, University of Wisconsin - Milwaukee
Lines: 48
NNTP-Posting-Host: 129.89.7.4
In article <1r1996INNijp@hp-col.col.hp.com> johnr@col.hp.com (John T. Rasper) writes:
>Does anyone know the details of the interface (5 wire din) for the
>IR remote sensor & (2 wire IR repeater) for the ADCOM GTP-500II
>preamp?  The ADCOM part numbers are the XR-500II, SPM-500II, and
>IRA-500II.
>
>A cursory physical examination of the pre-amp connector indicates
>that the connector (5 pin din) may provide: (Viewed from connector front)
>
>      |
>   5     1     (pin ?) +?v @ ???mA
>    4   2      (pin ?) +/-?v @ ???mA
>      3        (pin 3) Signal Ground
>               (pin ?) Demodulated signal ?V-pp, ? polarity, ? mA drive
>               (pin ?) Signal to drive repeater LED (drives through 150ohm
>                       resistor) ?V-pp
>
>I assume that the repeater connectors (mini-plugs) drive the IR repeater
>LED's directly.  True?
>
>Can anyone fill in the ?'s.  Thanks.
>
Here's the scoop.  When you get your home brew receiver working, would
you be willing to share it with the rest of us?  I always wanted to
build my own but never have the time to fool around and design it.
pin 1:  signal ground
pin 2:  signal
pin 3:  always hot +6 volts
pin 4:  +6 volts, hot only when preamp is turned on
pin 5:  infrared repeater connectors
The infrared repeater jacks on the back of the preamp are not connected
to anything inside the preamp except the 5 pin connector pin #5.  There
is a 150 ohm resistor between the two jacks, with a 1.5K from pin 5 to
ground.
The signal pin #2 in the preamp is summed with the built in IR receiver.
They use a chip called CX20106A and a BJT to amplify the signal.  I would
imagine the logical way would be to duplicate this circuit and use
it as the external receiver.
If you need more info, let me know.
Randy      randyd@csd4.csd.uwm.edu
From: pat@fegmania.wustl.edu (Pat Niemeyer)
Subject: Re: Radar detector DETECTORS?
Organization: Washington University in Saint Louis, MO USA
Lines: 11
Reply-To: pat@fegmania.wustl.edu
NNTP-Posting-Host: fegmania.wustl.edu
Originator: pat@fegmania
>>>  Are any brands "quieter" than others?
>Yes some radar detectors are less detectable by radar detector
>detectors. ;-)
I have a Bel-966.
I just looked at the manual yesterday... and it does indeed claim to be
undetectable by RDD's.
Pat
From: gerrit@laosinh.stgt.sub.org (Gerrit Heitsch)
Subject: Re: 6551A and 6551 compatibility
Distribution: world
Organization: Lao-Sinh project (private UUCP site)
Lines: 31
In article <C5owvs.pr@world.std.com>, Internet Surfer writes:
> Does any one know if the 6551 is timing/pin compatible with the 6551..
No, the 6551A is able to operate in a 2 MHz system, the 6551 can only
take 1 MHz without problems.
If you see a 8551 made by MOS or CSG, take it, its a 6551A.
> It seems the 6551 has in iheirent bug with cts/rts handshaking and i need
> a suitable pin replacement to put in my serial card... possibly a buffered
> version perhaps?
I know no fixed version of the 6551. There are different possibilities
to work around this bug. The easiest is to tie _CTS to GND and
use _DSR or _DCD as _CTS. It should be easy to fix the software,
_DSR is bit 6 and DCD ist bit 5 of the Status Register (Read 6551
with RS1 = low and RS0 = high).
Using the _CTS-line can lead into big trouble. The 6551 _instantly_
stops transmission if _CTS goes high. This means, that you may
get only a half byte...
Gerrit
--
Gerrit Heitsch  Moenchweg 16  7038 Holzgerlingen  Germany
Logical adresses: UUCP: gerrit@laosinh.stgt.sub.org FIDO: (2:2407/106.9)
If we will ever be visited by Aliens, it will be very hard to explain, why a
lifeform, that is intelligent enough to build atomic weapons can be stupid
enough to do it. (taken from GEO special about space, page 88-91)
From: gerrit@laosinh.stgt.sub.org (Gerrit Heitsch)
Subject: Re: What's a good IC for RS232 -> TTL signals??
Distribution: world
Organization: Lao-Sinh project (private UUCP site)
Lines: 26
In article <C5nz60.99z@scraps.uucp>, Frank Holden KA3UWW writes:
> >I'm looking for an IC that will convert RS232 voltage levels to TTL voltage
> >levels.  Something relatively inexpensive would be nice, too.  Anyone have
> >a suggestion??  Thanks.
>
> Well it looks as if Digi-Key sells a chip with the number ICL232 that does what
> you want.  They are selling it for about $3.50...
Are you sure that he needs a two way converter? If he wants only
RS232->TTL I would suggest the MC1489, its very cheap (0.80 DM in
Germany). This chip needs only +5V. The MC1488 TTL->RS232-Converter
uses +12V and -12V.
BTW... The MAX232 and compatibles seem to be expensive in the USA...
I paid 2.95 DM for a ITS80272 (made by Harris), its absolutely
compatible with the MAX232 or the ICL232.
Gerrit
--
Gerrit Heitsch  Moenchweg 16  7038 Holzgerlingen  Germany
Logical adresses: UUCP: gerrit@laosinh.stgt.sub.org FIDO: (2:2407/106.9)
If we will ever be visited by Aliens, it will be very hard to explain, why a
lifeform, that is intelligent enough to build atomic weapons can be stupid
enough to do it. (taken from GEO special about space, page 88-91)
From: rmah@panix.com (Robert Mah)
Subject: Re: electronic parts in NYC?
Organization: PANIX Public Access Unix, NYC
Lines: 23
In <FRITZM.93Apr20225937@sun.panix.com> fritzm@panix.com (Fritz Mueller) writes:
>I just moved to NYC and wondered if there are any electronics hackers
>out there who could point me to places in NYC that sell individual
>electronic components (switches, pots, transformers, caps,
>...
Try Cables and Chips ... let me dig out a reciept ...
Here we are...
Cables & Chips at 121 Fulton Street, that's near South Street Seaport and
Wall Street.  Phone is 212-619-3132 and 800-843-4117.
However, when ordering there, be VERY exact or there's a good chance they'll
screw up.  Otherwise, they're pretty good, and they deliver too.
Cheers,
Rob
--
[----------------------------------------------------------------------]
[ Robert S. Mah   | Voice: 212-947-6507   | "Every day an adventure,   ]
[ One Step Beyond | EMail: rmah@panix.com |  every moment a challenge" ]
[----------------------------------------------------------------------]
From: fritzm@panix.com (Fritz Mueller)
Subject: electronic parts in NYC?
Organization: PANIX Public Access Unix, NYC
Lines: 18
Hey all:
I just moved to NYC and wondered if there are any electronics hackers
out there who could point me to places in NYC that sell individual
electronic components (switches, pots, transformers, caps,
transistors, etc.)  "Radio Shack" doesn't count (they have almost no
selection, and their prices are outrageous!)
I have particular interest in audio components (amplifier IC's, power
MOSFETS, output transformers, tubes and tube sockets, pan pots,
faders, etc.)
I have checked out a lot of 48th street and Canal street so far with
no luck.  Am I missing places, looking in the wrong place, or do I
have to resort to mail order?
thanks in advance,
--FritzM.
From: stevens@madvlsi.columbia.edu (Andy Stevens)
Subject: Re: decoupling caps - onboard
Organization: Columbia University
X-Posted-From: greece.madvlsi.columbia.edu
NNTP-Posting-Host: sol.ctr.columbia.edu
Lines: 14
In article <1993Apr20.173652.762@jarvis.csri.toronto.edu>, ravin@eecg.toronto.edu (Govindan Ravindran) writes:
|>         I would like to know if any one had any experience with having
|> on-board decoupling capacitors (inside a cmos chip) for the power
|> lines. Say I have a lot of space left im my pad limited design.
|> any data on the effect of oxide breakdown? any info or pointers
|> are appreciated.
DEC did this on their new alpha chip.  I'm sure you could call them up
and ask them how they did it (haha).
Actually, there are some details in their article in IEEE Journal of
Solid-State Circuits.  I think it was sometime around Nov.  1992.
--andy s.
From: kolstad@cae.wisc.edu (Joel Kolstad)
Subject: Re: How to the disks copy protected.
Organization: U of Wisconsin-Madison College of Engineering
Lines: 38
In article <sehari.735357542@du139-213.cc.iastate.edu> sehari@iastate.edu (Babak Sehari) writes:
>
>I have written a program and I want to market it.  I would like certain degree
>of protection, since my main custmers are individuals and not the
>cooperations.   I know laser hole burning method, and hardware key method,
>however, my  software is going to cost only $15.00, so I can not afford that.
>Also, at this low price I can not afford people make too many copy of my
>software. Well, I guess say upto %20 illigal copying is ok by me.
>
>However, I do not want someone to get a copy of PCTools and copy my software.
>Off course, I never meant to forbid the true hackers from copying, since they
>can develope a better program anyway.
I wouldn't bother with the copy protection, if I were you.  If you program
is any good, the pirates will have stripped the protection and will be
distributing the stripped version is well under a week.
Hardware methods prevent J. Random Loser from using his Copy II PC to pirate
your software, but doesn't stop anyone who knows a few people with enough
connections to "real" pirates who _will_ be able to defeat your "check for the
hole" code.
You may want to price your software (depending on what it is) a tad
higher... a price change from $15 to $25 probably would turn off very few
potentials buyers, and that way you could tolerate more pirates (whose
numbers don't change with the price).
As for the 20% pirating figure... ha, ha.  Of course, a lot of pirates just
have this "thing" about having pirated software, even if they never use it,
so perhaps that really wouldn't count towards 20%.  Even so, 20% is awfully
low.
---Joel Kolstad
P.S. -- I assume you're talking PC software.  If you're talking UNIX,
HP-48, or something else somewhat obscure, copy protection might be a
slightly more viable alternative.
From: mhald@lynx.dac.northeastern.edu (Mark Hald)
Subject: Re: Dayton Hamfest
Organization: Northeastern University, Boston, MA. 02115, USA
Distribution: usa
Lines: 13
I booked a hotel (Red Roof Inn) last week in Cincinnati (Blue Ash, which
is at the northern tip of the metro. Cincy area).  I chose it for a few
reasons.
1.  All hotels in and near Dayton were booked solid.
2.  This hotel is only costing $28/night.
3.  It was one of about 4 rooms left on the night I reserved.
4.  Cincinnati probably has more to to at night than Dayton.  I intend
to hit the riverboat entertainment at dusk!
If anyone has other suggestions for nightlife, please let me know of
other hot spots.  Thanks!
Mark
From: skipper@traider.ersys.edmonton.ab.ca (Mark Bevan)
Subject: Re: Need to find out number to a phone line
Reply-To: skipper@traider.ersys.edmonton.ab.ca (Mark Bevan)
Organization: Traiders of the Lost .ARC! - Edmonton, Alberta, Canada
Lines: 21
alee@ecs.umass.edu writes:
>
> Greetings!
>
>         Situation:  I have a phone jack mounted on a wall.  I don't
>                     know the number of the line.  And I don't want
>                     to call up the operator to place a trace on it.
>
>         Question:   Is there a certain device out there that I can
>                     use to find out the number to the line?
>         Thanks for any response.
>                                                     Al
>
>
Dial 511 and it sound tell you the number.
---
skipper@traider.ersys.edmonton.ab.ca (Mark Bevan)
Traiders of the Lost .ARC! - Edmonton, Alberta, Canada
From: cbruno@wpi.WPI.EDU (Christopher James Bruno)
Subject: Coil
Organization: Worcester Polytechnic Institute
Lines: 11
NNTP-Posting-Host: wpi.wpi.edu
Hey everyone, I'm new to this  newsgroup so please excuse me if this is a
dumb question....I want to build a crossover for my stereo and I need
a coil with an inductance of 6.8mH (actually I need 4).  I was wondering
if anyone knew where I could buy these or how to make these.  I've called
many places and no one I can find sells them.  If you have the answers just
E - mail me....
Thanks in advance....
Chris
From: dave@imax.imax.com (Dave Martindale)
Subject: Re: A question about 120VAC outlet wiring.
Organization: Imax Corporation, Mississauga Canada
Lines: 24
jeh@cmkrnl.com writes:
>
>Hmmm.  How are those orange "isolated ground" outlets (often used in
>computer rooms) wired?
They require two separate grounds.  One ground goes to the ground pin
of the outlet, and the other ground wire is connected to the outlet's
mounting tabs (and thus grounds the box and faceplate screw and metal
faceplate, if any).
The box/faceplate ground goes to the normal distribution panel ground.
The outlet ground-pin wire is generally connected to an insulated
busbar in the distribution panel which is, in turn, connected to
the building-entrance main ground by its own wire.
So the two separate ground systems are connected together at the
building's service entrance.  But one is also connected to every
grounded piece of electrical equipment in the whole building,
while the isolated ground is shared only by the equipment plugged
into isolated-ground outlets of that panel.  If someone happens
to accidentally short one phase of a 600V feeder to ground,
the main building ground is likely to have a lot of noise on it
until the breaker trips or the fuse blows, while the isolated
ground will remain relatively noise-free.
From: mtearle@gu.uwa.edu.au (Mark Tearle)
Subject: Re: Looking for Electronics Dept Info in Austrailia
Organization: The University of Western Australia
Lines: 37
NNTP-Posting-Host: mackerel.gu.uwa.edu.au
hjkim@hyowon.pusan.ac.kr (Hojoong Kim) writes:
>Hi Netters!
>I am looking for the list of universities in Austrailia, which has electronics department.
>I am considering to spend a year for research in Austrailia about communication area.�� I am interested in Mobile communication areas and spread spectrum communications etc.
>But I don't have any information about Austrailian Universities.
>Can anybody recommend a good university in co��mmunic��ation area?
>Any comments will be welcomed!
Can I suggest the University of Western Australia in Perth.
The weathers great, the people are great and our Electronic Engineering department is great.
I am a first year student here ... so I don't know much about what projects but I do know they have a good reputation in the fields of dsp and communications.  Ever heard of QPSX?  The people who own are ex-UWA ... so that gives an indication of what the department is like.
For more information
email: yianni@swanee.ee.uwa.edu.au
with the above request and he should be able to tell some more info
or write
Department of Electrical and Electronic Engineering
University of Western Australia
Stirling Highway
CRAWLEY 6009
Western Australia
Australia
Yours
Mark
mtearle@tartarus.uwa.edu.au
--
#***********************************************************************#
#  Mark Tearle                         |                                   #
#                                      |
#  email: mtearle@tartarus.uwa.edu.au  |
From: mtearle@gu.uwa.edu.au (Mark Tearle)
Subject: Re: Need to find out number to a phone line
Organization: The University of Western Australia
Lines: 14
NNTP-Posting-Host: mackerel.gu.uwa.edu.au
Well here in Australia you dial
11544
to get the number read back to you
if you live in the country include the area code of the nearest capital city
eg for wa 09 11544
Yours
Mark
--
#***********************************************************************#
#  Mark Tearle                         |                                   #
#                                      |
#  email: mtearle@tartarus.uwa.edu.au  |
From: squish@endor.uucp (Shishin Yamada)
Subject: Re: ATARI 2600 Processors
Organization: Aiken Computation Lab, Harvard University
Lines: 42
In article <93110.125951PCA103@psuvm.psu.edu> <PCA103@psuvm.psu.edu> writes:
>Does anyone know what processor the Atari 2600 used? What I'm looking for is th
>e pin-outs for the Atari 2600.... the schematics for it it... does anyone have
>any idea where I could find this or any related information? This is very impor
>tant. Also, are the ROM chips that were used fo rthe 2600 games still available
>, or were they propreitary? Please email me with any responces, as this is very
> important.. Thanks a million...
>
>BTW- Anyone who works/has worked for Atari, I could really use your help with i
>nfo on the old 2600, please email me if you are willing to help me.... thatnks
>alot!!
>
>-Peter
The Atari 2600 used a 6502 CPU, just like their entire 8-bit line
(400, 800,1200,1400, 1440, 130xe, 65xe computers, as well as the 5200
game machine). The 2600 had some extra ASIC chips that were basically
modified graphics chips and PIA's for the joysticks. Later model 2600
might have incorporated many of the chips into one ASCI, as the weight
of the machines and part count decreased a lot over the years.
Additionally, I think the 2600 used 2K, 4K, and up to 8K of ROM for
their games. I have no idea how much RAM it had to work with, but I
would hazard a guess of 2 or 4K RAM. Think comes from a lot of hacking
with the 800 and 130xe computers. And occasionally hacking with the
2600 (fixing it for monitor composite video use, and audio hookups).
Also I tryed to make a cartridge-less system that stored the ROM into
a RAM cartridge that could be loaded up at some prior time (a way to
backup cartridges). I've heard of a setup like this where games could
be bought (cheaply) on FSK-recorded tapes, then you would load them
into a special RAM cartidge, and play them.
Anyways, if you're interested in looking for 2600 equipment, we've got
two 2600 machines around (one composite A/V modified), and lotsa
cartridges. Willing to sell for reasonable offer + shipping and
handling. Don't play it anymore, since going to computers + Nintendo
(interested in that too?).
Hope that helps your question... I might grab some 6502's out too,
since they must be fun to play with (as microcontrollers).
-shishin "squish" yamada
squish@endor.harvard.edu
From: fishman@panix.com (Harvey Fishman)
Subject: Re: electronic parts in NYC?
Organization: PANIX Public Access Unix, NYC
Lines: 11
There are also a couple or three places on West 45th between Fifth and
Sixth.
Harvey
--
----------------------------------------------------------------------------
Harvey Fishman   |
fishman@panix.com | You don't get smart except by asking stupid questions.
718-258-7276    |
From: ketil@edb.tih.no (Ketil Albertsen,TIH)
Subject: Re: How to the disks copy protected.
Organization: T I H / T I S I P
Posting-Front-End: Winix Conference v 92.05.15  1.20 (running under MS-Windows)
Lines: 20
In article <1993Apr20.230749.12821@reed.edu>, mblock@reed.edu (Matt Block) writes:
>	I guess what I am saying is that your question is difficult, if not
>impossible, to answer.  What exactly do you want to know?  Do you need a good
>one for a project you are working on?  How secure must it be?  Are you trying
>to crack one that someone else has used?  I can probably make suggestions,
>assuming the activity is strictly legal.  (In general, it is a BAD idea,
>legally, to tamper with copy protection.  It can also lead to corruption of
>files which you necessarily do not have back ups of (being as they are copy
>protected,) which can be devestating.)  Do you have absolutely no ideas for
>practical applications, and are merely curious?
>	Please clear up those questions, and I'll try to help as much as I
>can.
May we interpret this as an offer to volunteer as editor for a
"Copy protection FAQ" ? I am quite sure that I am not alone welcoming such
an initiative! *I* will volunteer to ask some of the questions, if you will
provide the answers :-)
Ketil Albertsen
From: frode@dxcern.cern.ch (Frode Weierud)
Subject: Magstrip Card Reader Info
Keywords: Magstripe, Card Reader, American Magnetics, Magnetics
Reply-To: frode@dxcern.cern.ch
Organization: CERN European Lab for Particle Physics
Lines: 26
Can somebody please help me with information about an
American Magnetics Corporation Magstripe Card Reader that
I recently bought locally from a surplus dealer.
On the rear it has the following information:
American Magnetics Corporation
Carson, CA, USA
Magstripe Card Reader
Model 41,
P/N 507500 - 2300112311
It is fitted with a cable with a RS232 Cannon 25-pin connector on
the end and has a separate power connector like the once used with
wall chargers.
Frode
**************************************************************************
*	Frode Weierud		Phone	:	41 22 7674794		 *
*	CERN, SL		Fax	:	41 22 7823676		 *
*	CH-1211 Geneva 	23	E-mail	:	frode@dxcern.cern.ch	 *
*	Switzerland			   or	weierud@cernvm.cern.ch	 *
**************************************************************************
From: elr@trintex.uucp (Ed Ravin)
Subject: Re: electronic parts in NYC?
Organization: Why me?
Lines: 19
Taft Electronics, 45th Street between 5th & 6th -- the only one left in
what was once an entire district of electronics stores.  A little expensive.
Trans-Am Electronics, Canal Street near 7th Ave -- lots of surplus type
stuff.
Several other electronics or "surplus" type places are still on Canal
Street.
I think Bronx Wholesale Radio is still in business -- Fordham Road not
too far from Arthur Avenue in the Bronx.  Also in the Bronx is NorthEastern
(or was it Northwestern?  Northeast Electronics?) on Jerome Avenue near
Bedford Park Boulevard.  They're mostly a TV parts supply house, but when
I was building CB radio projects, they were quite handy..
--
Ed Ravin               | "A TV cop fires a gun three times an hour.  A real cop
Prodigy Services Co.   |  fires a gun only once every five years."
White Plains, NY 10601 |------------d i s c l a i m e r - w a s - h e r e -----
+1-914-993-4737        | elr@trintex.uucp or elr%trintex@uunet.uu.net
From: wayne@uva386.schools.virginia.edu (Tony Wayne)
Subject: speaker impedance help needed
Organization: Virginia's Public Education Network (Charlottesville)
Lines: 7
I want to connect a very small "home-made" speaker
up to the headphone jack on my macintosh LC for an experiment.
The dc resistance of the speaker is 1 ohm.  Any ideas how I can
do this safely?  I think I need some kind of an impedance
transformer or something.?
-tony
wayne@uva386.school.virginia.edu
From: cfb@fc.hp.com (Charlie Brett)
Subject: FET-TRONS(sp?)
Nntp-Posting-Host: hpfcmgw.fc.hp.com
Organization: Hewlett-Packard Fort Collins Site
X-Newsreader: TIN [version 1.1 PL8.5]
Lines: 5
Has anyone ever heard of FET-TRONS (or is it FETRONS, FETTRONS, ...).
These were FET replacement modules for vacuum tubes. I'm looking for
applications where they were used.
Charlie Brett - HP Ft. Collins
From: cfb@fc.hp.com (Charlie Brett)
Subject: Re: Los Angeles Freeway traffic reports
Nntp-Posting-Host: hpfcmgw.fc.hp.com
Organization: Hewlett-Packard Fort Collins Site
X-Newsreader: TIN [version 1.1 PL8.5]
Lines: 21
: While driving through the middle of nowhere, I picked up KNBR, AM 1070,
: a clear-channel station based in Los Angeles. They had an ad
: claiming that they were able to get traffic flow information from
: all of the thousands of traffic sensors that CalTrans has placed
: under the pavement. Does CalTrans sell this info? Does KNBR have
: an exclusive? What's the deal?
: ==Doug "Former L.A. commuter" Claar
You were right the second time, it is KNX. Believe it or not, I also
listen to KNX in the evenings here in Colorado! It's kind of fun driving
through the country listening to traffic jams on the 405. Back to your
original question. Yes, there are sensors just past every on-ramp and
off-ramp on the freeways. They're the same sensors used at most stoplights
now (coils in the pavement). You might want to give CalTrans a call or
even ask Bill Keene (KNX's traffic reporter). I doubt if just anyone can
get the information, but it would be worth asking just in case you can
get it.
Charlie Brett (former LA commuter)  Ft. Collins, CO
From: v064mb9k@ubvmsb.cc.buffalo.edu (NEIL B. GANDLER)
Subject: Radio Electronics Free information card
Organization: University at Buffalo
Lines: 8
News-Software: VAX/VMS VNEWS 1.41
Nntp-Posting-Host: ubvmsb.cc.buffalo.edu
How does the radio Electronics free information cards work.
Do they just send you some general information about the companies that
advertise in their magazine or does it also give you sign you up for a
catalog.
Neil Gandler
From: bob@kc2wz.bubble.org (Bob Billson)
Subject: Re: subliminal message flashing on TV
Organization: Color Computer 3: Tandy's 'game' machine
Lines: 13
kennehra@logic.camp.clarkson.edu (Rich"TheMan"Kennehan) says:
>Hi.  I was doing research on subliminal suggestion for a psychology
>paper, and I read that one researcher flashed hidden messages on the
>TV screen at 1/200ths of a second.  Is that possible?  I thought the
Take a look over in alt.folklore.urban.  There is a thread about subliminal
messages on TV.  The fact that subliminal messages don't work aside, an image
can't be flashed on a TV screen fast enough to not be noticed.
--
Bob Billson, KC2WZ                          | internet: bob@kc2wz.bubble.org
$nail:  21 Bates Way,  Westfield, NJ 07090  | uucp:     ...!uunet!kc2wz!bob
"Friends don't let friends run DOS" -- Microware
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: Laser vs Bubblejet?
Organization: Northeastern Ohio Universities College of Medicine
Lines: 29
FYI:  The actual horizontal dot placement resoution of an HP
deskjet is 1/600th inch.  The electronics and dynamics of the ink
cartridge, however, limit you to generating dots at 300 per inch.
On almost any paper, the ink wicks more than 1/300th inch anyway.
The method of depositing and fusing toner of a laster printer
results in much less spread than ink drop technology.
It doesn't take much investigation to see that the mechanical and
electronic complement of a laser printer is more complex than
inexpensive ink jet printers.  Recall also that laser printers
offer a much higher throughput:  10 ppm for a laser versus about 1
ppm for an ink jet printer.
Something else to think about is the cost of consumables over the
life of the printer.  A 3000 page yield toner cartridge is about
$US 75-80 at discount while HP high capacity (~500-1000 page yield)
cartridges are about $US 22 at discount.  It could be that over the
life cycle of the printer that consumables for laser printers are
less than ink jet printers.  It is getting progressively closer
between the two technologies.  Laser printers are usually desinged
for higher duty cycles in pages per month and longer product
replacement cycles.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: ragee@vdoe386.vak12ed.edu (Randy Agee)
Subject: Radar detector DETECTORS?
Organization: Virginia's Public Education Network (Richmond)
Lines: 27
Several years back one of the radar detectors manufacturers, in
defiance to Virginia's law against radar detectors, passed out
thousands of fake cardboard radar detectors at truck stops near
the Virginia State lines.  At that time there were no radar
detector Detectors!  I am not sure of the impact but I would
imagine that enforcement of the law by visually sighting a
radar detector became difficult - if not impossible!
As I said earlier, efforts to throw out or eliminate the VA law
against radar detectors has been in vain.  In fact, effective
Jan. 1, 1993, the fine for possession of a radar detector
accessable to the driver of a vehicle in VA is now $250.00.
I have noted an interesting anomality with my Alinco DR-100 2
meter ham transceiver.... It will make a *cheap* radar detector
scream!  I am not sure of the range, but it is obvious by the
brake lights that it can be at least 50 feet at 50 watts! :-)
==============================================================================
Randy T. Agee - WB4BZX           | At some point, you probably pondered The
P.O. Box 2120 - 20th floor       | Meaning of Life, and you came up with a
Virginia Department of Education | satisfactory answer, which has or has not
Richmond, VA 23216-2120          | stood the test of time, or you shrugged
Phone (804) 225-2669             | mightily, muttered "Beats the heck out of
ragee@vdoe386.vak12ed.edu        | me," and ordered a cheeseburger.
=============================================================================
From: wtm@uhura.neoucom.edu (Bill Mayhew)
Subject: Re: How to the disks copy protected.
Organization: Northeastern Ohio Universities College of Medicine
Lines: 23
Write a good manual to go with the software.  The hassle of
photocopying the manual is offset by simplicity of purchasing
the package for only $15.  Also, consider offering an inexpensive
but attractive perc for registered users.  For instance, a coffee
mug.  You could produce and mail the incentive for a couple of
dollars, so consider pricing the product at $17.95.
You're lucky if only 20% of the instances of your program in use
are non-licensed users.
The best approach is to estimate your loss and accomodate that into
your price structure.  Sure it hurts legitimate users, but too bad.
Retailers have to charge off loss to shoplifters onto paying
customers; the software industry is the same.
Unless your product is exceptionally unique, using an ostensibly
copy-proof disk will just send your customers to the competetion.
--
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED
From: csulo@csv.warwick.ac.uk (Mr M J Brown)
Subject: 600RPM Floopy drives - UPDATE!
Organization: Computing Services, University of Warwick, UK
Lines: 26
Distribution: world
NNTP-Posting-Host: clover.csv.warwick.ac.uk
Many thanks to those who replied to my appeal for info on a drive I have
which is 3.5" 600RPM!!
I now have some information on how to modify this for use with a BBC B
computer. Not only do you have to change the speed from 600 to 300 rpm
(tried that) but also change 8 components in the Rec/Play section to allow
for the lower data rate (250kbit, not 500kbit as it was designed for) and also
change the Recording Current to allow for the low data rate/rev speed!
Hopefully this should sort it all out .... not bad for 9 quid (normally 32
quid and upwards ....)
The drive is a JVC MDP series drive ...
=============================================================================
_/      _/   _/   _/  _/   _/_/_/_/   |
_/_/  _/_/   _/   _/_/     _/          |         Michael Brown
_/  _/  _/   _/   _/       _/_/         |
_/      _/   _/   _/_/     _/            |    csulo@csv.warwick.ac.uk
_/      _/   _/   _/  _/   _/_/_/_/  _/   |     mjb@dcs.warwick.ac.uk
|
=============================================================================
Lost interest ?? It's so bad I've lost apathy!
=============================================================================
From: einari@rhi.hi.is (Einar Indridason)
Subject: Re: How to the disks copy protected.
Lines: 31
Nntp-Posting-Host: hengill.rhi.hi.is
In <1993Apr21.085848.12704W@lumina.edb.tih.no> ketil@edb.tih.no (Ketil Albertsen,TIH) writes:
>May we interpret this as an offer to volunteer as editor for a
>"Copy protection FAQ" ? I am quite sure that I am not alone welcoming such
>an initiative! *I* will volunteer to ask some of the questions, if you will
>provide the answers :-)
Ok, here could be the first question or answer or something:
Q: I want to copyprotect a program I wrote.  How should I do it?
A: You would be wise not to copyprotect that program.  You see, those
people that wants to get a cracked copy of your program will go to
various length to crack your program, and some of those crackers
are good, and know the common tricks.
So, the copy protection wouldn't stop those.
Ok, then.  What about legitimate users?  Copy protection can be a hassle
for legitimate users, and can hinder them in their work, expecially
if there is some "key" item that can get lost.
So, the copy protection wouldn't help much of the legitimate users, but
would make life somewhat of a misery for them.
(This is my opinion, and I speak as a legitimate user :-)
You are of course free to have your opinion about this subject....
--
einari@rhi.hi.is
From: lgardi@uwovax.uwo.ca
Subject: Re: Long distance IR detection
Organization: University of Western Ont, London
Nntp-Posting-Host: hydra.uwo.ca
Lines: 31
In article <1993Apr20.183416.18744@dres.dnd.ca>, sburton@dres.dnd.ca (Stan Burton) writes:
>
> --
>
> I would like to be able to detect the angular position (low accuracy) of an
> IR emitting source at a distance of about 100 meters (more is better) in
> daylight.  The IR source could be emitting a signature; I'm leaning toward
> 30 KHz square wave with 50% duty cycle.
>
> I am considering the use of a quadrant detector from Centronic Inc. to give
> information to a pan/tilt head to point the sensor and thus determine the
> angles.  For the source I am considering wazing the heck out of an IR LED(s),
> possibly an Optek OP290 or Motorola MLED81.  Wazing would mean at least 1 Amp
> current pulses.  At this current the duty cycle of the LED drops to 10% and I
> would need to cycle five of them in turn to get the 50% required.
>
> Has anyone done something like this?
>
Why don't you just run one LED at 60 KHz and use a flip flop at the receiving
end to divide by 2 and give you a good square 30KHz signal.
Just a thought.
LORI
> Stan Burton (DND/CRAD/DRES/DTD/MSS/AGCG)                 sburton@dres.dnd.ca
> (403) 544-4737     DRE Suffield, Box 4000, Medicine Hat, AB, Canada, T1A 8K6
--
<<<RED FISHY WINS>>>
Lori Gardi				(519) 661-2111 ext 8695
Dept. of Astronomy,			lgardi@uwovax.uwo.ca
University of Western Ontario
London, ON, CANADA, N6A 3K7
From: leblanc@cvm.msu.edu (Pat Leblanc)
Subject: wireless data transfer
Organization: Michigan State University, College of Veterinary Medicine
Lines: 5
NNTP-Posting-Host: inst0027.cvm.msu.edu
I am involved with a Michigan company that has an application requiring
wireless data transfer.  If you have expertise or information that may
assist us in this project, please contact me (INTERNET: leblanc@cvm.msu.
edu).
From: hcb@netcom.com (H. C. Bowman)
Subject: 8x oversampling CD player
Keywords: oversampling, CD, digitized audio
Organization: Box of Rain Productions
Lines: 27
Hello--
I just bought a new portable CD player for the office, and I notice that
it proudly proclaims "8 TIMES OVERSAMPLING" on the box.  Now while I think
I understand what oversampling is (the rate of discrete "samples"
exceeds the highest frequency component of interest by some factor),
I don't understand this "8 TIMES" business...  It seems to me that when
I bought my first CD player (was it REALLY 10 years ago?!), the specs
said "4 TIMES" ...  Could someone please tell me whether I'm getting
senile?  If I'm not, then what good does it do for the player to take
samples at a higher rate?  If I really wanted better fidelity, wouldn't
I have to have the same higher rate of sampling during the recording
process?  Furthermore, am I wrong in interpreting the sampling rate
(from the player's point of view) as being the same thing as the data
rate for the bit stream coming off the optical medium?  Does this mean
that the data rate (related to the rotational speed of the disk) has
changed since 1983?
I'm so confused...
--Cliff
--
| Clifford Bowman, Box 1890, Russellville, AR  72811 | hcb@netcom.com |
| I'm pretty sure the world *isn't* fair...  If it   | (501) 968-2232 |
| were, I'd be a lot worse off!                      |      N5TJU     |
From: edhall@rand.org (Ed Hall)
Subject: Re: Los Angeles Freeway traffic reports
Organization: RAND
Lines: 29
Nntp-Posting-Host: ives.rand.org
In article <C5uLqn.Gpw@fc.hp.com> cfb@fc.hp.com (Charlie Brett) writes:
>: While driving through the middle of nowhere, I picked up [KNX], AM 1070,
>: a clear-channel station based in Los Angeles. They had an ad
>: claiming that they were able to get traffic flow information from
>: all of the thousands of traffic sensors that CalTrans has placed
>: under the pavement. Does CalTrans sell this info? Does [KNX] have
>: an exclusive? What's the deal?
Well, they claim they are the only radio broadcaster with this
information.  But the city's cable channel (35 in CableVision areas)
shows this information map during travel times (6-9am and 4-7pm, I
believe).  Most of the major LA freeways are covered.  The
computer-generated map shows green, yellow, red, or flashing red
(respectively: <40mph, 25-40mph, >25mph, and "incident"--I might be off
a little on the speeds, since this is from memory).
I often look at this display in the morning to see if I really want to
fight the traffic on the Sepulveda Pass or work from home for a little
while to wait for it to clear.
Another poster explained the origin of the information: sensors (embedded
wire loops) in the pavement near ramps and every half mile or so.  CalTrans
has had a "big board" driven from this data in their traffic control center
for some time.  I don't know if they are selling the data or if anyone
with the equipment necessary for its transmission and display can have
it.
-Ed Hall
edhall@rand.org
From: jimmy@fireflare (Jimmy Mosquera)
Subject: Re: help - how to construct home-built battery for 3rd grade sci report
Keywords: 3rd grade science report
Nntp-Posting-Host: fireflare
Organization: Jet Propulsion Laboratory (NASA)
Distribution: usa
Lines: 22
In article <C5GE69.Lo0@athena.cs.uga.edu> mcovingt@aisun3.ai.uga.edu (Michael Covington) writes:
>Almost any two dissimilar metals in almost any electrically conductive
>liquid.
>
>Example: Copper and zinc in Coca-Cola...
>
>copper and galvanized steel nails in a lemon...
>
>Don't expect much power out, but it should be easily detectable
>with a voltmeter.
>
>--
>:-  Michael A. Covington, Associate Research Scientist        :    *****
>:-  Artificial Intelligence Programs      mcovingt@ai.uga.edu :  *********
>:-  The University of Georgia              phone 706 542-0358 :   *  *  *
>:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :  ** *** **  <><
A copper and a zinc rod in a potato also work nice.
From: martyj@mrcnext.cso.uiuc.edu (martin johnson)
Subject: Hi Volt from battery
Keywords: capacitive discharge
Organization: University of Illinois at Urbana
Lines: 13
I need a small battery powered hi voltage capacitive discharge supply to
deliver ~6 joules at 250 volts. This implies a 200uf cap. I have built
a very satisfactorily operating version from a MAX641, but do not like
the idea of using a $6 single source part. It seems that the ubiquitous
camera flash circuit is what I want, but I cant get mine apart without
breaking it. I would appreciate receiving the circuit description or
a source of one. I have already looked in several electronics circuits
handbooks to no avail. Thanx
--
______________________________________________
|  martin johnson      martyj@uiuc.edu       |
|  "mind your business", on first US coin    |
|____________________________________________|
From: acm@Sun.COM (Andrew MacRae)
Subject: Re: arcade style buttons and joysticks
Reply-To: acm@Sun.COM (Andrew MacRae)
Organization: Sun Microsystems, Mountain View CA
Lines: 14
NNTP-Posting-Host: grendal.corp.sun.com
In article <1993Apr21.024036.7394@lynx.dac.northeastern.edu>, dnewman@lynx.dac.northeastern.edu (David F. Newman) writes:
> Hi there,
> Can anyone tell me where it is possible to purchase controls found
> on most arcade style games.  Many projects I am working on would
> be greatly augmented if I could implement them.  Thanx in advance.
HAP controls just outside Chicago sells these.  I don't remember which
suburb they are in.  The prices are pretty reasonable and they are
easy to hook up.  I bought a new coin mechanism from them for $25.00
a couple of years ago.
Andrew MacRae
From: whit@carson.u.washington.edu (John Whitmore)
Subject: Re: Suggestions  on Audio relays ???
Organization: University of Washington, Seattle
Lines: 20
NNTP-Posting-Host: carson.u.washington.edu
In article <C5qsBF.IEK@ms.uky.edu> billq@ms.uky.edu (Billy Quinn) writes:
>I built a little project using the radio shack 5vdc relays to switch
>audio.  I got pretty bad 'clicks' when the thing switched.
>	Is there a good relay/relay circuit that I can use for switching
>audio, so that there will be *NO* noise of any kind on the audio lines.
With relays alone, you will always get a transient when
you abruptly turn ON or OFF any channel.  If you don't want to hear
the transient, use some other device (a photoresistor-output optoisolator
is the usual sort of thing) to gently MUTE the signal, then switch,
THEN remove the power from the lamp in the optoisolator.
It used to be standard practice to employ photoresistors
in switching audio, because the photoresistor time delay (a few
thousandths of a second) kept any noise in the digital side (which
drives the lamp) from contaminating the audio.  And, the devices
are cheaper than relays.
John Whitmore
From: whit@carson.u.washington.edu (John Whitmore)
Subject: Re: Radar detector DETECTORS?
Article-I.D.: shelley.1r4cucINNham
Distribution: na
Organization: University of Washington, Seattle
Lines: 18
NNTP-Posting-Host: carson.u.washington.edu
In article <1993Apr19.231050.2196@Rapnet.Sanders.Lockheed.Com> babb@rapnet.sanders.lockheed.com (Scott Babb) writes:
>Brian Day (bday@lambda.msfc.nasa.gov) wrote:
>: On December 29, 1992, it was illegal to operate a radar detector
>: in the state of Virginia.  If one got caught, one got fined $65.00.
>The Federal Communications Act of 1934 made it *legal* for you to
>operate a radio receiver of any kind, on any frequency (including
>X, K, and Ka bands) in the United States.
And the Commonwealth of Virginia has not exactly butted
against the issue on those grounds.  The claim is that AS A MATTER
OF TRAFFIC SAFETY one is not allowed to have a functioning radar
detector on the dashboard while operating a motor vehicle.
Yes, the argument is bogus, BUT... it hasn't been successfully
challenged in court.  Yet.
John Whitmore
From: jbore@cosmos.shearson.com (Joe Bore)
Subject: Re: Need to find out number to a phone line
In-Reply-To: alee@ecs.umass.edu's message of 18 Apr 93 15:04:10 GMT
Organization: Lehman Brothers
Lines: 33
try finding a friend that has caller id, then give him a call...
jb
In article <20756.2bd16dea@ecs.umass.edu> alee@ecs.umass.edu writes:
Path: shearson.com!uupsi!psinntp!uunet!haven.umd.edu!darwin.sura.net!newsserver.jvnc.net!howland.reston.ans.net!noc.near.net!nic.umass.edu!risky.ecs.umass.edu!umaecs!alee
From: alee@ecs.umass.edu
Newsgroups: sci.electronics
Date: 18 Apr 93 15:04:10 GMT
Lines: 13
Greetings!
Situation:  I have a phone jack mounted on a wall.  I don't
know the number of the line.  And I don't want
to call up the operator to place a trace on it.
Question:   Is there a certain device out there that I can
use to find out the number to the line?
Thanks for any response.
Al
--
-------------------------------------------------------------------------------
Joe Bore					 | "Life is Short...Code Hard"
jbore@Shearson.COM | ...!uunet!shearson.com!jbore|
(212)464-3431, Beeper:  (212)396-4248		 |
Subject: Re: Power, signal surges in home...
From: emd@ham.almanac.bc.ca
Distribution: world
Organization: Robert Smits
Lines: 21
vanderby@mprgate.mpr.ca (David Vanderbyl) writes:
> drand@spinner.osf.org (Douglas S. Rand) writes:
>
> >   Hams can legally run up to 1500 watts.  It is very unlikely, however,
> >   that a ham would be running that kind of power from a car.
> >
> >Not possible either.  You'd need about a 300 amp alternator for
> >just the amplifier.
>
> It is too possible.  As the original poster said "it is very unlikely"
> but definately possible.  (Can you say batteries?)
I've even seen pictures of an installation where the ham pulled a little
trailer behind his car with a 4KW generator, and ran the full legal limit
while mobile. I don't know what his gas mileage was like, though, or
where he found resonators able to stand the gaff.
emd@ham.almanac.bc.ca (Robert Smits Ladysmith BC)
From: tom@afthree.as.arizona.edu (Thomas J. Trebisky)
Subject: Re: A question about 120VAC outlet wiring..
Keywords: outlet
Organization: Steward Observatory, Univ. of Arizona, Tucson
Lines: 19
crichmon@sedona.intel.com (Chris Richmond) writes:
>Well, my house was built just last year, and the breaker box is wired the
>same way.  All the white and ground wires are on a common bus.  Except for
>the 220V circuits, only black wires are hooked to the breakers.  It was
>the same way in the last two houses I had also.  Are you sure this is wrong?
>I still have the building inspector's signature on the breaker box.
The point is that the original poster was talking about connecting
ground and neutral in the *outlet* box (big NO NO), and you are talking
about them being connected in the breaker box (as things should be).
If this is not obvious, the point is that there should be current
flow in the white, i.e. neutral/return wires when things in the
house are operating.  There should not be any flow in the ground wires
unless there is a fault condition.  Notice also that in the breaker box
there is a wire leading from the above-mentioned junction to earth ground,
usually a pipe or spike driven into the ground.
--
Tom Trebisky	ttrebisky@as.arizona.edu
From: kolstad@cae.wisc.edu (Joel Kolstad)
Subject: Re: 8x oversampling CD player
Organization: U of Wisconsin-Madison College of Engineering
Keywords: oversampling, CD, digitized audio
Lines: 40
In article <hcbC5un9L.DD0@netcom.com> hcb@netcom.com (H. C. Bowman) writes:
>
>Hello--
>
>I just bought a new portable CD player for the office, and I notice that
>it proudly proclaims "8 TIMES OVERSAMPLING" on the box.  Now while I think
>I understand what oversampling is (the rate of discrete "samples"
>exceeds the highest frequency component of interest by some factor),
>I don't understand this "8 TIMES" business...  It seems to me that when
>I bought my first CD player (was it REALLY 10 years ago?!), the specs
>said "4 TIMES" ...  Could someone please tell me whether I'm getting
>senile?  If I'm not, then what good does it do for the player to take
>samples at a higher rate?  If I really wanted better fidelity, wouldn't
>I have to have the same higher rate of sampling during the recording
>process?  Furthermore, am I wrong in interpreting the sampling rate
>(from the player's point of view) as being the same thing as the data
>rate for the bit stream coming off the optical medium?  Does this mean
>that the data rate (related to the rotational speed of the disk) has
>changed since 1983?
[Note: I just tried to figure this stuff out about a month ago myself, from
various people on the net, so I could be wrong.]
The data is only ever read once (barring mistracks and such, of course),
and eventually gets turned into 44.1 KHz, 16 bit, two channel data.
Oversampling takes two discrete data points, and interpolates n-1 points
between them for n times oversampling.  When I asked, people said that the
interpolation was not simply linear interpolation, but significantly more
complicated.
Anyway, then, the purpose of oversampling is to move the "effective"
sampling rate up to n times 44.1 KHz, in order to use higher frequency
antialiasing filters.  For the same quality filter, higher oversampling
lets you build cheaper filters, whereas for the same price filter, higher
oversamplings lets you build better filters.  So, assuming the quality of
all other components in a CD player remained the same, oversampling should
allow a manufacturer to produce _slightly_ better sound due to anti-alias
filtering.
---Joel Kolstad
From: galen@picea.CFNR.ColoState.EDU (Galen Watts)
Subject: Re: Suggestions  on Audio relays ???
Nntp-Posting-Host: storm.cfnr.colostate.edu
Organization:  Colorado Concert Sound
Lines: 25
In article <1993Apr20.102756.1709@mala.bc.ca> wagner@mala.bc.ca (TOM WAGNER, Wizzard of old Audio/Visual Equipment........Nanaimo Campus) writes:
>In article <C5r60r.4ID@megatest.com>, alung@megatest.com (Aaron Lung) writes:
>> In article <C5qsBF.IEK@ms.uky.edu> billq@ms.uky.edu (Billy Quinn) writes:
>>>I built a little project using the radio shack 5vdc relays to switch
>>>audio.  I got pretty bad 'clicks' when the thing switched.  I was doing
>>>My question is:
>>>	Is there a good relay/relay circuit that I can use for switching
>>>audio, so that there will be *NO* noise of any kind on the audio lines.
>>
>> Are you switching high level signals or low level signals like pre-amp
>A novel circuit I used to build was a primitive "optical isolator".. It consists
>of a resistive photocell and a lamp, all packaged in a tube.  When the lamp is
>off the cell is high resistance.  Turn the lamp on and the resistance lowers
I use an H11F1   FET optoisolater to switch microphone level signals.
There is no click, since I put a .1uF cap across the LED.  Distortion
measurement are very low with mic level, and they went up to 0.03% at a
+ 14 dB line level.  All I did was put the FET in series with one leg
of the balanced line.  No hums, pops, just audio jumping out of silence.
The FET runs about 100 million ohms with the LED dark and drops to 150-200
ohms with it on.
Hey, it works, and works well.
Galen Watts, KF0YJ
From: schaefer@imag.imag.fr (Arno Schaefer)
Subject: Re: How to the disks copy protected.
Nntp-Posting-Host: silene
Organization: Institut Imag, Grenoble, France
Lines: 38
In article <1993Apr21.085848.12704W@lumina.edb.tih.no>, ketil@edb.tih.no (Ketil Albertsen,TIH) writes:
|> In article <1993Apr20.230749.12821@reed.edu>, mblock@reed.edu (Matt Block) writes:
|>
|> >	I guess what I am saying is that your question is difficult, if not
|> >impossible, to answer.  What exactly do you want to know?  Do you need a good
|> >one for a project you are working on?  How secure must it be?  Are you trying
|> >to crack one that someone else has used?  I can probably make suggestions,
|> >assuming the activity is strictly legal.  (In general, it is a BAD idea,
|> >legally, to tamper with copy protection.  It can also lead to corruption of
|> >files which you necessarily do not have back ups of (being as they are copy
|> >protected,) which can be devestating.)  Do you have absolutely no ideas for
|> >practical applications, and are merely curious?
|> >	Please clear up those questions, and I'll try to help as much as I
|> >can.
|>
|> May we interpret this as an offer to volunteer as editor for a
|> "Copy protection FAQ" ? I am quite sure that I am not alone welcoming such
|> an initiative! *I* will volunteer to ask some of the questions, if you will
|> provide the answers :-)
|>
|> Ketil Albertsen
Hey, now will you stop encouraging him? Copy protection only serves one pur-
pose: to keep the honest buyer from making (legal) backup copies. It will
definitely not stop any pirates. If you want to protect you soft, supply a
good documentation and support. This is IMHO the *only* way of effectively pro-
tecting software.
Best Regards,
Arno
--
--------------------------------------------------------------------------------
Arno Schaefer				ENSIMAG, 2e Annee
Email: schaefer@silene.imag.fr
Tel.: (33) 76 51 79 95			:-)
------- No, you're not paranoid - the world is really out to get you -----------
From: CONRADIE@firga.sun.ac.za (Gerrit Conradie)
Subject: Re: arcade style buttons and joysticks
Organization: University of Stellenbosch, SA
Lines: 8
In article <1993Apr21.024036.7394@lynx.dac.northeastern.edu> dnewman@lynx.dac.northeastern.edu (David F. Newman) writes:
>Subject: arcade style buttons and joysticks
>Can anyone tell me where it is possible to purchase controls found
>on most arcade style games.  Many projects I am working on would
What about the common joystick found in all computer shops?
- gerrit
From: galen@picea.CFNR.ColoState.EDU (Galen Watts)
Subject: Re: Beginner's RF ???
Distribution: na
Nntp-Posting-Host: storm.cfnr.colostate.edu
Organization: College of Natural Resources, Colo. State Univ.
Lines: 16
In article <C5sr8H.JpH@cbnewsl.cb.att.com> klink@cbnewsl.cb.att.com (steven.r.klinkner) writes:
>Can anybody recommend a good, application-oriented beginner's reference
>to RF circuits?
>Steve Klinkner                AT&T Bell Labs               srk@boeing.att.com
I have the ARRL Handbook for the Radio AMateur, and I'm getting the
Solid STate Design for the Radio Amateur.
The handbook is $25 and Solid State is $12 from ARRL, 225 Main, Newington,
CT 06111 but you should be able to find them at electronics or amateur radio
stores.
ARRL will want $5 or so for shipping.
Good Luck,
Galen Watts, KF0YJ
From: henslelf@nextwork.Rose-Hulman.Edu. (Lige F Hensley)
Subject: Re: 68HC16 public domain software?
Organization: Computer Science Department at Rose-Hulman
Lines: 14
NNTP-Posting-Host: g222-26.nextwork.rose-hulman.edu
Keywords: 68hc16
In article <murashiea.15@mail.beckman.com>  writes:
> Does anyone know of an FTP site where I might find public
> domain software for the Motorola 68HC16 microprocessor?
> I am looking for a basic interpreter/compilier or a 'C'
> compiler.  Thanks in advance.
> 					Ed Murashie
Yep, at:
oak.oakland.edu
they have a couple different 68HC16 things in
/pub/msdos/emulators
and get the file
00-index.txt
for a list of what they have.
lige
From: Daniel.J.Stern@dartmouth.edu (Daniel J. Stern)
Subject: Seeking info on wear on monitors
X-Posted-From: InterNews 1.0b16@dartmouth.edu
Organization: Dartmouth College, Hanover, NH
Lines: 12
We are Dartmouth engineering students.We are looking for documented
data regarding the wear associated with turning on an off a monitor and
how it relates to power consumption.  Interested in a comparison
between the wear on a monitor which is left on continuously and one
which is turned off when not in use.
Please personalize E-mail to: ds@Dartmouth.edu
Thank you,
Dan Stern
Oliver Weir
From: exuptr@exu.ericsson.se (Patrick Taylor, The Sounding Board)
Subject: Re: How to the disks copy protected.
Nntp-Posting-Host: 138.85.253.85
Organization: Ericsson Network Systems, Inc.
X-Disclaimer: This article was posted by a user at Ericsson.
Any opinions expressed are strictly those of the
user and not necessarily those of Ericsson.
Lines: 36
In article <1993Apr21.131908.29582@uhura.neoucom.edu> wtm@uhura.neoucom.edu (Bill Mayhew) writes:
>From: wtm@uhura.neoucom.edu (Bill Mayhew)
>Subject: Re: How to the disks copy protected.
>Date: Wed, 21 Apr 1993 13:19:08 GMT
>Write a good manual to go with the software.  The hassle of
>photocopying the manual is offset by simplicity of purchasing
>the package for only $15.  Also, consider offering an inexpensive
>but attractive perc for registered users.  For instance, a coffee
>mug.  You could produce and mail the incentive for a couple of
>dollars, so consider pricing the product at $17.95.
Or, _documentation_ for the program ;-).  A lot of shareware out there is
very similar in the approach - send in your money, and you get
documentation, and a free upgrade to the latest version.  Perhaps even
support of some small degree.  Whatever you want to offer that is "better"
than the circulating version.
>You're lucky if only 20% of the instances of your program in use
>are non-licensed users.
Figure about 50%, as I have seen.
>The best approach is to estimate your loss and accomodate that into
>your price structure.  Sure it hurts legitimate users, but too bad.
It doesn't really hurt legit users.  Shareware is still much cheaper than
the alternatives.
----------------------------------------------------------------------------
---------Visit the SOUNDING BOARD BBS +1 214 596 2915, a Wildcat! BBS-------
ObDis: All opinions are specifically disclaimed. No one is responsible.
Patrick Taylor, Ericsson Network Systems  THX-1138
exuptr@exu.ericsson.se                    "Don't let the .se fool you"
From: henslelf@nextwork.Rose-Hulman.Edu. (Lige F Hensley)
Subject: Re: what to do with old 256k SIMMs?
Organization: Computer Science Department at Rose-Hulman
Lines: 11
NNTP-Posting-Host: g222-26.nextwork.rose-hulman.edu
In article <120466@netnews.upenn.edu> jhaines@eniac.seas.upenn.edu (Jason
Haines) writes:
>
> 	I was wondering if people had any good uses for old
> 256k SIMMs.  I have a bunch of them for the Apple Mac
> and I know lots of other people do to.  I have tried to
> sell them but have gotten NO interest.
>
> 	So, if you have an inovative use (or want to buy
> some SIMMs  8-) )
Sure I'll give you 10 bucks for all of them
From: baden@sys6626.bison.mb.ca (baden de bari)
Subject: _Exhausted student needing HELP!
Organization: System 6626 BBS, Winnipeg Manitoba Canada
Lines: 40
Well, I've now been working on this DAMNED stepper controller board
since 9pm.  It's now 6am... I'm pissed off.  Period.  Alright, I can
drive the steppers through the 3479P's; no problem (that's with the
6-wire steppers, 2 to +, and the other 4 are the phase lines).  Problem
1:  I've got some 4 wire steppers.  I put the darkest line to + and the
other 3 to the 3479P... worked, kinda.  Tried it with a printer stepper
(moves the head back and forth, 4 wires), didn't work too well.  It
would
shift back and forth (use something like a 4017 instead?)  Also I've
been
trying to get a bunch of NPN's to work with it... NO LUCK... tried
PNP's,
still NO LUCK!!!  I don't know if I'm cursed on this or what, but I feel
my brain slowly frying with the thought of STEPPER ... ARGGG!!!
I don't know what's wrong with the transistor hook-up (to-220
pkg
type), also tryed the 2n2222-pkg type... no luck.
I'm going to try getting some z's, and I hope
you
can help me with this problem.
If someone can please help me with this soon, it would be greatly
appreciated...
Thanks.
_________________________________________________
Inspiration  |   ___                             |
comes to     |  \   o  baden@sys6626.bison.mb.ca |
those who    | (  ^  ) baden@inqmind.bison.mb.ca |
seek the     |   /-\      =] Baden de Bari [=    |
unknown.     |                                   |
-------------------------------------------------
l
From: babb@sciences.sdsu.edu (J. Babb)
Subject: Re: Circuit Cellar Ink address?
Organization: SDSU - LARC
Lines: 14
Distribution: na
NNTP-Posting-Host: larc.sdsu.edu
In article <1qvlmaINNhuu@shelley.u.washington.edu>,
ptorre@hardy.u.washington.edu (Phil Torre) wrote:
>
> Is CCI still published?  If so, does anyone have their address?
Circuit Cellar Inc.
4 Park St.  Suite 20
Vernon, CT  06066
(203)875-2751
Jeff Babb
babb@sciences.sdsu.edu   babb@ucssun1.sdsu.edu
Programmer, SDSU - LARC
From: klink@cbnewsl.cb.att.com (steven.r.klinkner)
Subject: Beginner's RF ???
Organization: AT&T Bell Laboratories
Distribution: na
Lines: 14
Can anybody recommend a good, application-oriented beginner's reference
to RF circuits?
I am pretty good on theory & know what different types of modulation mean,
but don't have a lot of practical experience.  A book detailing working
circuits of different types (modulation, power, frequency, what is legal,
what is not, et cetera), would be very helpful.
Thanks.
-----------------------------------------------------------------------------
Steve Klinkner                AT&T Bell Labs               srk@boeing.att.com
att!boeing!srk
-----------------------------------------------------------------------------
From: jam@ameslab.gov (Jerry Musselman)
Subject: UART needed
Organization: Ames Laboratory, ISU
Lines: 9
I need to find a UART that will interface to an 8051 and do the following:
-250k baud, 8 data bits, 2 stop bits, no parity
-ability to do BREAK detect (IRQ or output pin)
-IRQ on character received
I'm using a Dallas DS2250 at 16 Mhz (8051 clone), but it won't do
break detect.  I've looked at the 6850, 8251, 7201, 2661, etc...
Any help would be appriciated!!!
From: rg@futserv.austin.ibm.com (R.G. Keen)
Subject: EICO tube tester repairs?
Reply-To: ...futserv.austin.ibm.com!rg
Organization: IBM Coporation - Advanced Workstations and Systems.
Lines: 14
I had the good luck to obtain an EICO dynamic conductance
tube tester for a song. Unfortunately, I was a little out of
key; the only thing wrong with it was an open meter movement.
Does anyone know where I can find either another meter movement
like it, a dead-but-not-the-meter-dead unit, or schematics
to specify the current scale of the meter movement? I can cut
and paste a more sensitive movement in if I can find what the
full scale current was. Or... is EICO still contactable?
The thing is a model 666 -nope, not a joke or any sort of snide
reference.
R.G.
From: uli@izfm.uni-stuttgart.de (Uli Allgeier)
Subject: Re: PADS Question - How do I go from a schematic -> PCB?
Organization: Comp.Center (RUS), U of Stuttgart, FRG
Lines: 38
NNTP-Posting-Host: pc8.izfm.uni-stuttgart.de
Hi!
In article <C5svup.I4I@news.cso.uiuc.edu> rky57514@uxa.cso.uiuc.edu (Tall Cool One ) writes:
>After I have produced a schematic with PADS-LOGIC, how do I import it into
>PADS-PCB to create a PCB pattern?  The only way I've gotten it to work is
>to output a FutureNet netlist, and then import this into PADS-PCB.  Is there
>another way of doing this?  I didn't see any information in the instructions
>provided, but I might have missed something.  Any suggestions would be
>greatly appreciated.  Thanks!
Sorry, it's german, but I hope you understand it.
Uebertragung der Schaltplan-Daten (*.SCH) in die Board-Daten
(*.JOB):
PADS-LOGIC:
In/Out
Reports
Net List
Select      PADS-PCB
Net List Output file name
-> filename angeben
PADS-PCB:
In/Out
Ascii In
Ascii input file name
-> filename angeben
Errors aoutput file name
-> filename angeben, nicht CR
Jetzt sind alle Bauteile auf einem Haufen und muessen mit Move
verteilt werden.
Viele Gruesse
Uli
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: how can 0.022 uF be different from two 0.047 in series?!
Organization: U of Toronto Zoology
Lines: 13
In article <1993Apr19.185326.9830@Princeton.EDU> mg@cs.princeton.edu (Michael Golan) writes:
>The board itself is also identical, with room for all three caps. The
>US/Can versions is clearly indicated in both places.
>
>How does that make sense? 0.047/2 is 0.0235, essentially 0.022 for caps
>(there are just standard caps, no special W/type/precision).
This may be a safety issue; the CSA is more paranoid in certain areas than
UL and such.  Two caps in series means that you don't have a short if one
of them shorts.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
- Kipling           |  henry@zoo.toronto.edu  utzoo!henry
From: camter28@astro.ocis.temple.edu (Carter Ames)
Subject: Lead Acid batteries & Concrete?
Organization: Temple University
Lines: 15
Nntp-Posting-Host: astro.ocis.temple.edu
X-Newsreader: TIN [version 1.1 PL8]
I was just wondering one thing, actually two. ( I hope that this is the
proper place to post this subject)
Why does a lead acid battery discharge and become dead (totally unuseable)
when stored on a concrete floor?
I decided to bring the battery in from the lawn mower and the motorcycle
from the unheated garage this year, *to preserve them* and I just
went to use them and noticed that not only do they not work, but
they act like the two terminals are shorted.  I asked a friend
and he said that you should never do that, 'cause it ruins them,
but he couldn't tell me why.
thanks
camter28@astro.ocis.temple.edu
From: wb9omc@dynamo.ecn.purdue.edu (Duane P Mantick)
Subject: Re: IR remote control receiver
Organization: Purdue University Engineering Computer Network
Lines: 29
ab616@Freenet.carleton.ca (Marc Dion) writes:
>For a project of my own, I would like to build a Infra-Red Remote control
>receiver (for regular VCRs and TVs remotes).  Does anybody have any info
>or tips on how to build such receiver ?
>In particular,
>a) which photo detector should I use (which wavelength do remotes use) ?
>b) which ICs or circuit should I use ?
>c) any suggestions for circuit layout
>Please reply to this group (if you wish), but as well via e-mail (my
>link to usenet is not always available).
I'd like to see this info as well.  As for wavelength, I think
you're primarily going to find two - 880 nM +/- a bit, and/or 950 nM
+/- a bit.  Usually it is about 10 nM either way.  The two most common
I have seen were 880 and 950 but I have also heard of 890 and 940.
I'm not sure that the 10 nM one way or another will make a great deal of
difference.
Another suggestion - find a brand of TV that uses an IR remote,
and go look at the SAMS photofact for it.  You can often find some very
detailed schematics and parts list for not only the receiver but the
transmitter as well, including carrier freq. specs. and tone decoding
specs. if the system uses that.
Duane
From: philc@macs.ee.mcgill.ca (Phil Crawley)
Subject: Read only if going to ISCAS93 in Chicago
Keywords: Soccer, ISCAS93
Lines: 20
Nntp-Posting-Host: kirk.ee.mcgill.ca
Organization: McGill University - MACS Laboratory, Montreal, CANADA.
This is message is only of interest to those going to
International Symposium on Circuits and Systems that is being
held in Chicago this May.
I checking to see if there is any people out there who would be
interested in getting together for a pickup game of soccer during
the off hours of the conference. If so could you e-mail me at:
philc@macs.ee.mcgill.ca
I'll bring a ball. If you know someone who is going to the
conference and you know that they are avid soccer players
please pass on this message to them. Also if someone in
Chicago is going to the conference please let me know if
there is any field near the hotel where we can play.
Thanks. Bye.
Philip Crawley
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: HELP: MC146818A Real Time Clock Standby Mode
Organization: U of Toronto Zoology
Lines: 20
In article <1r0b69INN5ct@flash.pax.tpa.com.au> mgregory@flash.pax.tpa.com.au (Martin John Gregory) writes:
>I am having trouble obtaining the specified standby current drain from
>a MC146818A Real Time Clock...
>lowest current drain I can acheive at 3.7V Vcc is 150uA.  This is
>three times the specified MAXIMUM...
>1) Made sure that RESET/ is asserted for Trlh after powerup, and AS is
>   low during this time.
>2) Made sure that there is a cycle on AS after the negation of RD/ or
>   WR/ during which STBY/ was asserted...
Are any of the inputs to the chip coming from TTL?  Standby-drain specs
for CMOS chips typically apply only if inputs are pulled all the way down
to zero or all the way up to Vcc.  TTL isn't good at doing the former and
it won't do the latter at all without help from pullup resistors.  This
sort of thing can easily multiply power consumption by a considerable
factor, because the CMOS transistors that are supposed to be OFF aren't
all the way hard OFF.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
- Kipling           |  henry@zoo.toronto.edu  utzoo!henry
From: pyeatt@Texaco.com (Larry D. Pyeatt)
Subject: Membrane keypad with custom legend.
Nntp-Posting-Host: 211.2.1.197
Organization: Texaco
Lines: 16
I had a catalog with membrane keypads, but I dunno what
happened to it, and it was so long ago that I forget the
name of the company.  Anyway, you could make your own
legend and slip it behind the bezel.  Really nice and
reasonably priced.  Can anyone tell me where to get some
more of these critters?  I've tried several places, but
none of them seem to have keypads which allow you to use
your own legend.
Any suggestion would be appreciated.
--
Larry D. Pyeatt                 The views expressed here are not
Internet : pyeatt@texaco.com    those of my employer or of anyone
Voice    : (713) 975-4056       that I know of with the possible
exception of myself.
From: dclaar@cup.hp.com (Doug Claar)
Subject: Los Angeles Freeway traffic reports
Nntp-Posting-Host: hprtnyc.cup.hp.com
Organization: Hewlett-Packard
X-Newsreader: TIN [version 1.1 PL8.9]
Lines: 4
oops, that's KNX 1070. KNBR is up in 'Frisco, and down at 680.
==Doug "San Fran can't be 'the city': Jack Webb told me so" Claar
From: wb9omc@dynamo.ecn.purdue.edu (Duane P Mantick)
Subject: Re: Long distance IR detection
Organization: Purdue University Engineering Computer Network
Lines: 44
sburton@dres.dnd.ca (Stan Burton) writes:
>I would like to be able to detect the angular position (low accuracy) of an
>IR emitting source at a distance of about 100 meters (more is better) in
>daylight.  The IR source could be emitting a signature; I'm leaning toward
>30 KHz square wave with 50% duty cycle.
>I am considering the use of a quadrant detector from Centronic Inc. to give
>information to a pan/tilt head to point the sensor and thus determine the
>angles.  For the source I am considering wazing the heck out of an IR LED(s),
>possibly an Optek OP290 or Motorola MLED81.  Wazing would mean at least 1 Amp
>current pulses.  At this current the duty cycle of the LED drops to 10% and I
>would need to cycle five of them in turn to get the 50% required.
>Has anyone done something like this?
Yeesh, you WILL be nailing those IRLEDs.  May I suggest getting your
mitts on the Siemens SFH484-2 IRLED?  This unit is designed to take some big
current pulses if you can get your duty cycle down a bit.  It will output
nearly a watt (975 mW) with REAL short duty cycle times.
(nice thing about the SFH484-2 is that it is CHEAP.  I got mine for about
50 cents a piece, even though I had to buy 100 of them....)
BTW, I have seen IRLEDs with outputs up to 6 watts...honest,
6 WATTS.  I don't have the book here at work so I can't recall the company
name.  The 6 watter ain't cheap, around $108 but if you want some power,
mamamia, that's pretty hot.  They also have a 4 watt, a 2 watt and a
1 watt device in their line, and will sell small quan. to individuals.
If you are interested, I can find the book at home and get the
pertinent info.
Now, as for the position detector, you might try ELTEC in Florida.
Phone number listed in the 92/93 ETID is 904-253-5328.  They seem like
nice people.  Their specialty is passive infrared detection devices,
so they might be able to help you out.
I'm curious about your applications if you don't mind saying.
The device sounds like it could be useful in a lasertag game, although you'd
need to up your carrier signal concept to 58.8 KHz......
Duane
From: willisw@willisw.ENG.CLEMSON.edu (Bill Willis)
Subject: Answers to many electronics Questions
Organization: Engineering Services, Clemson University
Lines: 10
I have notice a lot of electronics questions by people who are obviously not
"tuned-in" to electronics.  Many of them have rather simple answers, and
many of them require a circuit diagram.
Rather than muck up the network, why don't you write to me, send a self-
addressed, stamped envelop, and I'll answer your questions, if I can.
W. L. Willis, P. E.
114 Fern Circle
Clemson, SC 29631
From: paula@nlbbs.com (Paula Stockholm)
Subject: Re: Need to find out number to a phone line
Reply-To: paula@nlbbs.com <Paula Stockholm>
Organization: The Northern Lights BBS, Portland, ME  * 207-761-4782 *
Lines: 7
X-Newsreader: ZipNews Reader/Mailer v0.92d (Beta)
In most areas of the country, serviced by ESS (or CESS), your phone
--
* * * * * * * * * * * * * * * * * * * * * * * * * * *
*               paula@nlbbs.com                     *
*  Paula Stockholm            Cumberland, Maine USA *
* * * * * * * * * * * * * * * * * * * * * * * * * * *
From: kn1@cunixa.cc.columbia.edu (Kimball Ng)
Subject: Re: Laser vs Bubblejet?
Nntp-Posting-Host: cunixa.cc.columbia.edu
Reply-To: kn1@cunixa.cc.columbia.edu (Kimball Ng)
Organization: Columbia University
Lines: 44
kolstad@cae.wisc.edu (Joel Kolstad) writes:
>One other thing... there are bubblejets, and then there are BubbleJets.
>There are a few bubblejets out there that produce rather mediocre output
>(such as HP's dinky little BubbleJet), whereas most produce really good
>looking output (such as HP's DeskJets).  IBM and Canon both produce some of
>the really good style bubblejets.
>P.S. -- If you're in the market for a portable bubblejet printer, I can
>highly recommend the HP Portable DeskJet, although I've heard the portable
>Canons are good too (I needed PCL support, myself).  With the DeskJet
>Portable, you even get an undocumented PCMCIA card slot!
I second that suggestion.  Although I don't own the HP Portable Deskjet,
I *do* own the HP Deskjet 500.  It gives the nicest outputs, with only
a minor loss of quality.   For all intensive purposes (papers, letters,
resumes), I treat my Deskjet like a laser printer (You *do* have to
look a bit closely to see the blurs in the characters).  Only one
grudge, the ink that HP gives you does smudge rather quickly in the
presence of moisture (Even though the ink is waterproof).  However,
you would have to spend about $500 more for laser quality.
The cannon bubblejets are nice, however they don't seem to have as
much support (eg: drivers for popular programs) as the HP ink-jets.
Also HP Deskjet (regular,plus,500,500c) accepts xerox paper (I believe
that the cut-sheet feeder is an option for the cannon bubblejet).
If you don't mind refilling your printer with cheap ink (say
fountain-pen ink), then the HP deskjets are *very* cheap to maintain
(I paid $3.50 for my last bottle of ink and I expect it to last 9
months).
-Kimball (who doesn't work for HP, but just loves his printer
very much!)
PS: I have a question for you netters, I'm too afraid to refill with
the waterproof inks they sell in art-supply houses because I had brought
a bottle of waterproof ink and it clogged up my cartridge. I
wonder what is a 'good' waterproof ink (aside from buying refill-kits)
to refill my cartridge?
From: paj@uk.co.gec-mrc (Paul Johnson)
Subject: Re: CAD Program for Electronics?
Reply-To: paj@uk.co.gec-mrc (Paul Johnson)
Organization: GEC-Marconi Research Centre, Great Baddow, UK
Lines: 30
In article <1993Apr17.211126.23467@norfolk.vak12ed.edu> fculpepp@norfolk.vak12ed.edu (Fred W. Culpepper) writes:
>I am making a search for a CAD program that does a decent job
>of making schematic drawings.  The program needs to be in
>MS-DOS, Windows if possible.
>
>What I want the CAD program to do is to draw diagrams by
>dragging elements onto the screen, and in this the elements
>needed are as diverse as vacuum tubes to ICs (case with pins).
>It also needs to have provision for adding legends to the
>components as well as their values.  In other words I want to
>produce quality drawings.  Printout would be to either 24 pin
>dot-matrix and/or Laser Printer.
I would suggest Draw for Windows (by Micrografx).  I have this on my
home box.  Its quite impressive and only cost UKL100.  It has a rather
nice clip-art library facility which you can expand with your own
drawings.  There is no circuit component clip-art included, but you
could add your own quite easily.
It works with any Windows printer driver of course, and can also
export embedded postscript and PCX files.
Note: I am not connected with Micrografx in any way.
Paul.
--
Paul Johnson (paj@gec-mrc.co.uk).	    | Tel: +44 245 73331 ext 3245
--------------------------------------------+----------------------------------
These ideas and others like them can be had | GEC-Marconi Research is not
for $0.02 each from any reputable idealist. | responsible for my opinions
From: gerald.belton@ozonehole.com (Gerald Belton)
Subject: help - how to constru
Distribution: world
Organization: Ozone Online Operations, Inc. - New Orleans, LA
Reply-To: gerald.belton@ozonehole.com (Gerald Belton)
Lines: 27
>Dean Anneser (anneser@pwa-b.uucp) wrote:
>: My 9 yr old son has signed up to do a science report on batteries.  I was
>: wondering if anyone could provide me with some information as to how to
>: construct a home-built battery.  In my grade school days, I remember seei
>: the 'ice cube tray' version, but I don't remember what to use as a good
>: electrolyte or what the easily obtainable metals were.
>:
>: Thank you in advance.
>I remember watching a whole "Mr. Wizzard" program on this subject when
>I was a kid.  The battery constructed on the program which made the
>biggest impression on me, and generated the most power, was made using
>a galvanized bucket (for the zinc) and a copper toilet tank float.  The
>electrolyte was sauerkraut!
Take a lemon.  Stick a copper strip into the lemon.  Stick a galvanized
nail in about 1 to 1-1/2 inches from the copper strip.  You should get
about 1/2 volt from it - enough to light an LED.
* SLMR 2.1 * Support your medical examiner, die strangely.
----
The Ozone Hole BBS * A Private Bulletin Board Service * (504)891-3142
3 Full Service Nodes * USRobotics 16.8K bps * 10 Gigs * 100,000 Files
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From: gerald.belton@ozonehole.com (Gerald Belton)
Subject: Food Dehydrators
Distribution: world
Organization: Ozone Online Operations, Inc. - New Orleans, LA
Reply-To: gerald.belton@ozonehole.com (Gerald Belton)
Lines: 39
>Does anybody out there have one of those food dehydrators I've been seeing
>all over late-night TV recently? I was wondering if they use forced air, hea
>or both. If there's heat involved, anybody know what temperature they run at
>My wife would like one and I'm not inclined to pay >$100.00 for a box, a fan
>and a heater. Seems to me you should be able to throw a dehydrator together
>for just a few bucks. Heck, the technology is only what? 1,000 years old?
You can learn how to build a deyhdrator very easily from the book, "The
Hungry Hiker's Guide to Good Food," by Gretchen McHugh.  The heat source
is a 100 watt light bulb.  Basically, it's a vertical wooden box with
ventilation holes in the top and bottom (lots of them, you want the air
to flow).  The light bulb goes in the bottom, and wire cake racks are
spaced every 6" starting about 10" above the bulb.
Or, at a slightly higher cost in electricity, you can do what I do:  Use
your oven.  (NOTE - I do this in an electric oven; some gas ovens may
not have a low enough setting).  Put food to be dried on cookie tins or
racks in the oven.  Set oven to 140 degrees (the lowest setting on my
oven - if yours goes down to 120 that's probably even better.)  Stick a
wooden spoon or something across the front corner of the oven and close
the door on the spoon so that it stays open about an inch - this allows
for airflow.  Leave the stuff in the oven for 6 to 8 hours; check it
often, since this dries it much faster than the dehydrator.  If you are
using cookie sheets instead of racks, turn the stuff over halfway
through.
If you want more info, e-mail me since this isn't really the right sub
for this stuff.
gerald.belton@ozonehole.com
* SLMR 2.1 * I still miss my boss, but my aim is improving.
----
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From: gerald.belton@ozonehole.com (Gerald Belton)
Subject: Need to find out numb
Distribution: world
Organization: Ozone Online Operations, Inc. - New Orleans, LA
Reply-To: gerald.belton@ozonehole.com (Gerald Belton)
Lines: 24
AL>>        Question:   Is there a certain device out there that I can
AL>>                    use to find out the number to the line?
AL>>        Thanks for any response.
AL>>                                                    Al
AL>There is a number you can call which will return a synthesized
AL>voice telling you the number of the line.  Unfortunately, for the
AL>life of me I can't remember what it is. The telephone technicians
AL>use it all the time.  We used to play around with this in our
AL>dorm rooms since there were multiple phone lines running between
AL>rooms.
It probably wouldn't help for you to post the number, since it appears
to be different in each area.  For what it's worth, in the New Orleans
area the number is 998-877-6655 (easy to remember, what?)
* SLMR 2.1 * Ask me anything: if I don't know, I'll make up something.
----
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3 Full Service Nodes * USRobotics 16.8K bps * 10 Gigs * 100,000 Files
SKYDIVE New Orleans! * RIME Network Mail HUB * 500+ Usenet Newsgroups
Please route all questions or inquiries to:  postmaster@ozonehole.com
From: gerald.belton@ozonehole.com (Gerald Belton)
Subject: MC SBI mixer
Distribution: world
Organization: Ozone Online Operations, Inc. - New Orleans, LA
Reply-To: gerald.belton@ozonehole.com (Gerald Belton)
Lines: 32
MJM>HI, I was wondering if anyone would be able to help me on twwo related
MJM>subjects. I am currently learning about AM/FM receivers and recieving
MJM>circuits. I understand a lot of things ,but a few things I am confused
MJM>abuot. The first is the MIXER, to mix the RF and local oscillator
MJM>frequencies to make the IF. Does anyone have any cicruit diagrams (as
MJM>simple as possible) for this kind of mixer? I have come across a
MJM>MC-SBL mixer chip But I have not been able to find it in any catalogs
MJM>(ACTIVE,etc...)
MJM>Along the same note, are there any SIMPLE fm receiver circuits anyone
MJM>may have stashed away somewhere and they couold let me see?.
MJM>P.S. any REALLY GOOD BOOKS on AM/FM theory ALONG WITH DETAILED
MJM>ELECTRICAL DIAGRAMS would help a lot.
MJM>I have seen a lot of theory books with no circuits and a lot of
MJM>circuit books with no theory, but one without the other does not help.
Digi-key has the NE-622 chip which has a local oscillator and mixer on
one chip.
For a great combination of theory with actual circuits, the best
reference for non-engineers is probably the Radio Amateur's Handbook
from the ARRL.  Most library's have it in the reference section.
* SLMR 2.1 * If ignorance is bliss, why aren't there more happy folk?
----
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3 Full Service Nodes * USRobotics 16.8K bps * 10 Gigs * 100,000 Files
SKYDIVE New Orleans! * RIME Network Mail HUB * 500+ Usenet Newsgroups
Please route all questions or inquiries to:  postmaster@ozonehole.com
From: wayne@uva386.schools.virginia.edu (Tony Wayne)
Subject: Pink Noise
Organization: Virginia's Public Education Network (Charlottesville)
Lines: 4
What is Pink noise and how is it used in sound experiments?
-tony
wayne@uva386.schools.virginia.edu
From: lihan@ccwf.cc.utexas.edu (Bruce G. Bostwick)
Subject: Re: how can 0.022 uF be different from two 0.047 in series?!
Organization: The University of Texas at Austin, Austin TX
Lines: 13
Distribution: usa
NNTP-Posting-Host: doc.cc.utexas.edu
In article <C5uC68.19K@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>
>This may be a safety issue; the CSA is more paranoid in certain areas than
>UL and such.  Two caps in series means that you don't have a short if one
>of them shorts.
Not necessarily true; a short in one, if near the maximum series
voltage drop, will overvoltage the other one and short it too, more
--
<BGB>
lihan@ccwf.cc.utexas.edu        /   The only reason the world hasn't
(really Bruce Bostwick)        /   dissolved into total chaos is that
from the great state of TEXAS /   Murphy's Law also applies to Murphy.
From: lihan@ccwf.cc.utexas.edu (Bruce G. Bostwick)
Subject: Re: Membrane keypad with custom legend.
Organization: The University of Texas at Austin, Austin TX
Lines: 21
Distribution: usa
NNTP-Posting-Host: doc.cc.utexas.edu
In article <1993Apr21.125530.18387@texhrc.uucp> pyeatt@Texaco.com (Larry D. Pyeatt) writes:
>I had a catalog with membrane keypads, but I dunno what
>happened to it, and it was so long ago that I forget the
>name of the company.  Anyway, you could make your own
>legend and slip it behind the bezel.  Really nice and
>reasonably priced.  Can anyone tell me where to get some
>more of these critters?
For some reason the name Grayhill springs to mind -- saw something
like that in a Grayhill catalog, along with options for custom printed
overlays and a neat little electroluuminescent backing that would make
the whole shebang glow a nice shade of green ..
mighty handy if you're trying to key a door combination in the dark
and don't want to TURN ON THE &%#$!! LIGHT ..
--
<BGB>
lihan@ccwf.cc.utexas.edu        /   The only reason the world hasn't
(really Bruce Bostwick)        /   dissolved into total chaos is that
from the great state of TEXAS /   Murphy's Law also applies to Murphy.
From: andrew.payne@hal9k.ann-arbor.mi.us (Andrew Payne)
Subject: WANTED:  TCM3105 chips, small quantities
Distribution: world
Organization: HAL 9000 BBS, W-NET HQ, Ann Arbor, Michigan, USA
Reply-To: andrew.payne@hal9k.ann-arbor.mi.us (Andrew Payne)
Keywords: rec mod
Lines: 29
From: payne@crl.dec.com (Andrew Payne)
Message-ID: <1993Apr20.004418.11548@crl.dec.com>
Organization: DEC Cambridge Research Lab
Date: Tue, 20 Apr 1993 00:44:18 GMT
Does anyone know if a source for the TCM3105 modem chips (as used in the
Baycom and my PMP modems)?  Ideally, something that is geared toward
hobbyists:  small quantity, mail order, etc.
For years, we've been buying them from a distributor (Marshall) by the
hundreds for PMP kits.  But orders have dropped to the point where we can
no longer afford to offer this service.  And all of the distributors I've
checked have some crazy minimum order ($100, or so).
I'd like to find a source for those still interested in building PMP kits.
Any suggestions?
--
Andrew C. Payne
DEC Cambridge Research Lab
---
. R110B:Wnet HAL_9000
----
| HAL 9000 BBS:  QWK-to-Usenet gateway  | Four 14400 v.32bis dial-ins    |
| FREE Usenet mail and 200 newsgroups!  | PCBoard 14.5aM * uuPCB * Kmail |
| Call +1 313 663 4173 or 663 3959      +--------------------------------+
| Member of EFF, ASP, ASAD  * 1500MB disk * Serving Ann Arbor since 1988 |
From: andrew.payne@hal9k.ann-arbor.mi.us (Andrew Payne)
Subject: WANTED:  TCM3105 chips, small quantities
Distribution: world
Organization: HAL 9000 BBS, W-NET HQ, Ann Arbor, Michigan, USA
Reply-To: andrew.payne@hal9k.ann-arbor.mi.us (Andrew Payne)
Keywords: rec mod
Summary: Reposted by Keith Petersen
Lines: 29
From: payne@crl.dec.com (Andrew Payne)
Message-ID: <1993Apr20.004418.11548@crl.dec.com>
Organization: DEC Cambridge Research Lab
Date: Tue, 20 Apr 1993 00:44:18 GMT
Does anyone know if a source for the TCM3105 modem chips (as used in the
Baycom and my PMP modems)?  Ideally, something that is geared toward
hobbyists:  small quantity, mail order, etc.
For years, we've been buying them from a distributor (Marshall) by the
hundreds for PMP kits.  But orders have dropped to the point where we can
no longer afford to offer this service.  And all of the distributors I've
checked have some crazy minimum order ($100, or so).
I'd like to find a source for those still interested in building PMP kits.
Any suggestions?
--
Andrew C. Payne
DEC Cambridge Research Lab
---
. R110B:Wnet HAL_9000
----
| HAL 9000 BBS:  QWK-to-Usenet gateway  | Four 14400 v.32bis dial-ins    |
| FREE Usenet mail and 200 newsgroups!  | PCBoard 14.5aM * uuPCB * Kmail |
| Call +1 313 663 4173 or 663 3959      +--------------------------------+
| Member of EFF, ASP, ASAD  * 1500MB disk * Serving Ann Arbor since 1988 |
From: ulan@ee.ualberta.ca (Dale Ulan)
Subject: Part MC68SEC811E2
Nntp-Posting-Host: eigen.ee.ualberta.ca
Reply-To: ulan@ee.ualberta.ca (Dale Ulan)
Organization: University of Alberta Electrical Engineering
Distribution: na
Lines: 8
I know what the 68HC811E2 is all about, but I'm trying to figure
out what the 68SEC811E2 is... specifically, what does the SEC
stand for?
----
Dale Ulan   VE6DAU     ulan@ee.ualberta.ca
From: acooney@netcom.com (Alan Cooney)
Subject: Re: Los Angeles Freeway traffic reports
Organization: NETCOM On-line Communication Services (408 241-9760 guest)
X-Newsreader: TIN [version 1.1 PL6]
Lines: 48
I live in the San Francisco Bay Area, and word has it that
something similar is on its way here.  Since we apparently
don't have the sensor base you folks have, they're installing
cameras at strategic points along the freeways (initial tests
are going to be in the Santa Clara area I'm told), with the
video being piped into a command center they're building
somewhere in the East Bay.  I'm not sure if frame grabbers or
cheap labor will be used to interpret the data, but large
multi-colored status displays will show the various routes
using different colors to represent the various average speeds
for each stretch of highway.  An announcer will sit in front
of the status 'wall', and will relay continuous verbal traffic
status to those who want to receive it.  They're apparently also
looking into licensing a low-AM frequency to be dedicated to
providing continuous audio from this system.
In the mean time, they'll set up large incandescent display
boards along the test stretch to provide commuters with data
on traffic conditions up ahead.  My understanding is that the
system is subsidized as a pilot program, and information from it
will be available free of charge.  Perhaps the LA system is
similarly free or provided at an obviously subsidized rate (read
"cheap").
We also have the traffic reports that are broadcast on the SAP
audio channel of television channels 2 and 36.  These are verbal
reports, qualified with a identification tone to tell in-vehicle
receivers like the 'Auto Talk' that the information coming next is
applicable to a given area.  In LA, they're probably using some
other TV channels, but the concept is the same.  Try setting your
stereo TV or VCR to receive the SAP audio channel, and go station
jumping to find out which one is broadcasting this information.
I believe this program is also subsidized, making the in-vehicle
receivers cheap to purchase (and without having to incur monthly
fees to use it).  Since the makers of these in-vehicle receivers
don't have to pay for the broadcast (this may not be completely
true), they likely have no investment in keeping the system
up and running when the Cal Trans stuff hits the airwaves.  You
may have a nifty little TV audio receiver in your car, nothing
more, when this happens.  Perhaps a word to the wise...?  ;)
I think we'd all be interested in a summary post if you get more
info on how the LA system is networked and paid for.
Cheers,
Alan
<acooney@netcom.com>
From: cmwolf@mtu.edu (Engineer by Day - Asleep by Night)
Subject: Re: Answers to many electronics Questions
Organization: Michigan Technological University
X-Newsreader: TIN [version 1.1 PL8]
Lines: 19
Bill Willis (willisw@willisw.ENG.CLEMSON.edu) wrote:
: I have notice a lot of electronics questions by people who are obviously not
: "tuned-in" to electronics.  Many of them have rather simple answers, and
: many of them require a circuit diagram.
: Rather than muck up the network, why don't you write to me, send a self-
: addressed, stamped envelop, and I'll answer your questions, if I can.
: W. L. Willis, P. E.
: 114 Fern Circle
: Clemson, SC 29631
Because the network is quicker, easier, and free (at least to me).
--
------------------------------------------------------------------------------
Christopher Wolf             Electrical Engineer                cmwolf@mtu.edu
------------------------------------------------------------------------------
Remember, even if you win the Rat Race - You're still a rat.
From: cmwolf@mtu.edu (Engineer by Day - Asleep by Night)
Subject: Re: A question about 120VAC outlet wiring.
Organization: Michigan Technological University
X-Newsreader: TIN [version 1.1 PL8]
Lines: 13
Dave Martindale (dave@imax.imax.com) wrote:
: They require two separate grounds.  One ground goes to the ground pin
: of the outlet, and the other ground wire is connected to the outlet's
: mounting tabs (and thus grounds the box and faceplate screw and metal
: faceplate, if any).
I thought the ground WAS connected to the metal frame on the socket.
--
------------------------------------------------------------------------------
Christopher Wolf             Electrical Engineer                cmwolf@mtu.edu
------------------------------------------------------------------------------
Remember, even if you win the Rat Race - You're still a rat.
From: cmwolf@mtu.edu (Engineer by Day - Asleep by Night)
Subject: Re: Los Angeles Freeway traffic reports
Organization: Michigan Technological University
X-Newsreader: TIN [version 1.1 PL8]
Lines: 21
Charlie Brett (cfb@fc.hp.com) wrote:
: You were right the second time, it is KNX. Believe it or not, I also
: listen to KNX in the evenings here in Colorado! It's kind of fun driving
: through the country listening to traffic jams on the 405. Back to your
: original question. Yes, there are sensors just past every on-ramp and
: off-ramp on the freeways. They're the same sensors used at most stoplights
: now (coils in the pavement). You might want to give CalTrans a call or
: even ask Bill Keene (KNX's traffic reporter). I doubt if just anyone can
: get the information, but it would be worth asking just in case you can
: get it.
I seem to remember that they sell the information (and a computer connection)
to anyone willing to pay.
On the subject of the pavement sensors, can anyone tell me more about them?
--
------------------------------------------------------------------------------
Christopher Wolf             Electrical Engineer                cmwolf@mtu.edu
------------------------------------------------------------------------------
Remember, even if you win the Rat Race - You're still a rat.
From: acollins@uclink.berkeley.edu (Andy Collins)
Subject: Voltage regulation and current limiting
Organization: University of California, Berkeley
Lines: 37
NNTP-Posting-Host: uclink.berkeley.edu
Summary: Need help!!!
One not-so-quick question to throw out there for you guys...
For our class project, we need to design and build a power supply
to the following specs:
Voltatge:  adjustable from 1-12V
Current:   *limited* at 1A
Voltage must stay within 2% of designated value for I from 0-1A
AC ripple less than 5 mV (rms)
Of course, we can't just use an adjustable voltage, current-limiting
regulator chip ;^)
Our problem is with the current limiting (i.e. we've found stuff to
do the rest of the parts of the circuit).  What the supply must do,
if presented with a load which would draw more than 1A, given the
supply voltage, is reduce the voltage so that the current will equal
one amp.  Thus, if we were to short the thing with the ammeter, we
should read one amp.  If we measure the current through a 1 ohm
resistor at 12V, we should read one amp (and the output voltage, by
necessity, must be 1V.
The only basic idea we have seen for the current limiter involves
a circuit which will pull current off of the base of the output
power transistor, and therefore reduce the output.
So, does anybody have any ideas we could work from?
Thanks in advance.
Andy Collins, KC6YEY
acollins@uclink.berkeley.edu
ps: If anybody wants to flame this as a stupid project, I agree fully,
but I still have to do it, its graded ;^)
From: acooney@netcom.com (Alan Cooney)
Subject: Re: Membrane keypad with custom legend.
Organization: NETCOM On-line Communication Services (408 241-9760 guest)
X-Newsreader: TIN [version 1.1 PL6]
Distribution: usa
Lines: 21
Try the folks at Dimolex Corp., La Crescenta, CA 91214.
Their number is (818) 957-7001.  They make membrane keypads
that are very flat, in layouts from 2 to 128 keys.  They
have standard models, tactile models (with stainless domes
under each key to make a 'click' you can feel), as well as
backlit models.  Some of them can even be cut with scissors
to form a funky shape other than a rectangle.  Many of the
models are available in a 'kit' which includes a bezel,
colored and plain key covers, and rub on lettering to make
your own layout.  One piece prices aren't cheap, though,
as they want $10 for one four position pad *kit*, and $45
for a 40 position *kit*.
I have no affiliation with Dimolex or any company connected
with them.  I *have* purchased a couple of keypads from them,
and am pleased with what I got.
Cheers,
Alan
<acooney@netcom.com>
From: DRAMALECKI@ELECTRICAL.watstar.uwaterloo.ca (David Malecki)
Subject: Re: Building a UV flashlight
Lines: 40
Organization: University of Waterloo
In article <C5r6Lz.n25@panix.com> jhawk@panix.com (John Hawkinson) writes:
>My main question is the bulb: where can I get UV bulbs? Do they
>need a lot of power? etc., etc.
I've seen them in surplus stores.  All they are are fluorescent bulbs
without the phosphor, and a UV transparent bulb (special glass).  I've
also seen incandescent versions that you screw into an ordinary 120VAC
socket, probably not what you want.
>
>I'm not too concerned with whether it's long-wave or short-wave
>(but hey, if anyone has a cheap source of bulbs, I'll take both).
>
>One other thing: a friend of mine mentioned something about near-UV
>light being cheaper to get at than actual UV light. Does anyone
>know what he was referring to?
As far as I know, near UV (as opposed to far-UV) is longwave UV (near
the visible spectrum).  Longwave UV is safer as far as accidental (I hope)
exposure to the eyes.  As far as fluorescent minerals go (the reason a
friend has a UV lamp), some only respond to only one of short or long UV.
Hope this helps.
Dave.
>
>Thanks much.
>
>
>--
>John Hawkinson
>jhawk@panix.com
----------------------------------------------------------------------
| Who I am:  David Malecki                                             |
| Who you think I am:  dramalecki@electrical.watstar.uwaterloo.ca      |
|                                                                      |
----------------------------------------------------------------------
From: karplus@cse.ucsc.edu (Kevin Karplus)
Subject: Re: decoupling caps - onboard
Organization: University of California, Santa Cruz
Lines: 38
Reply-To: karplus@ce.ucsc.edu (Kevin Karplus)
NNTP-Posting-Host: ararat.ucsc.edu
I've used on-chip capacitors to reduce ground-bounce noise on a small
systolic array chip that had 50pF loads on the clock lines.
(Design was in 2-micron n-well cmos, using the MOSIS scalable design rules.)
Here are some thoughts on the bypass capacitors:
1) They don't help much with simultaneous output switching--there is
still a large inductance between the bypass capacitor and the
load capacitor (on both the signal line and the ground
return), so you still get ground and power line bounce.
2) They do help a lot with on-chip loads, as I had with the high load
on the clock lines.
3) The transients you are trying to suppress are really high
frequency, so forget about large areas of poly-thin-oxide-diff
capacitors, since the RC time constant is too large.
What I did is to make a metal2, metal, poly, diff sandwich,
but put a lot of holes in the poly layer, allowing frequent
diff-metal1 contacts.  I forget exactly how wide the poly
lines were.  If I were doing this design again, I'd probably
omit the diff altogether, and use a solid poly sheet instead,
using just m2, m1, and poly (and substrate, but that has such a high
resistance it can be ignored at these speeds).
4) You are probably better off trying to tune your circuit to run with
slightly slower edges and lower voltage swings (especially for
output signalling), than spending chip area on capacitors.
I had spare space on the die since the circuit was too big for
a MOSIS tiny chip, and the next size up was twice as big as I
needed.
Kevin Karplus
--
Kevin Karplus		karplus@ce.ucsc.edu
Due to budgetary constraints the light at the end of the tunnel is
being turned off.
From: Mike Diack <mike-d@staff.tc.umn.edu>
Subject: Anyone got 200+ Schadow switches with LED?
X-Xxmessage-Id: <A7FC6A05A602655F@dialup-slip-1-95.gw.umn.edu>
X-Xxdate: Thu, 22 Apr 93 15:28:05 GMT
Nntp-Posting-Host: dialup-slip-1-95.gw.umn.edu
Organization: persian cat & carpet co.
X-Useragent: Nuntius v1.1.1d7
Lines: 3
Name your price, cap colours & quantity available.
cheers
Mike
From: mycal@NetAcsys.com (Mycal)
Subject: Need to find out number to a phone line
Distribution: world
Organization: ACSYS, Inc.
Lines: 14
try comp.dcom -  I was reading a thread a while back about an 800 number
that you could dial.  worked here.  It was a sales line for sprint I think
telling you that you could have all your customers numbers using there
ANI, then it told you your number.  Should work with any modern switch.
mycal
---------------------------------------------------------------------------
PGP key on request.       mycal@netacsys.com
\ //
Mycal's way of skiing moguls:                                 // \
turn, turn, turn, air, survive, survive, survive...     No Risk, No Rush
From: mycal@NetAcsys.com (Mycal)
Subject: ATARI 2600 Processors
Distribution: world
Organization: ACSYS, Inc.
Lines: 19
For all people that are interested in every aspect of the 2600 try the
zine:
2600 connection
$1 cash to :
Timothy Duarte
PO Box N, 664
Westport, MA 02790
for sample
---------------------------------------------------------------------------
PGP key on request.       mycal@netacsys.com
\ //
Mycal's way of skiing moguls:                                 // \
turn, turn, turn, air, survive, survive, survive...     No Risk, No Rush
From: rubin@cis.ohio-state.edu (Daniel J Rubin)
Subject: Re: arcade style buttons and joysticks
Organization: The Ohio State University Dept. of Computer and Info. Science
Lines: 17
NNTP-Posting-Host: zion.cis.ohio-state.edu
> Hi there,
> Can anyone tell me where it is possible to purchase controls found
> on most arcade style games.  Many projects I am working on would
> be greatly augmented if I could implement them.  Thanx in advance.
Try Parts Express in Dayton, Ohio also.  They have a complete line of
professional arcade buttons, joysticks etc...
The have a 1-800 number so call 1-800-555-1212 and ask them what the 1-800
number for Part Express in Dayton, Ohio is.  I love the free 1-800 directory
assistance...
- Dan
--
Daniel Joseph Rubin     rubin@cis.ohio-state.edu
GO BENGALS!      GO BUCKS!
From: alan@apple.com (Alan Mimms)
Subject: Re: UART needed (really BREAK detect)
Organization: Apple Computer, Inc.
Lines: 26
In article <jam.19.735404158@ameslab.gov>, jam@ameslab.gov (Jerry
Musselman) wrote:
>
> I need to find a UART that will interface to an 8051 and do the following:
> 	-250k baud, 8 data bits, 2 stop bits, no parity
> 	-ability to do BREAK detect (IRQ or output pin)
> 	-IRQ on character received
>
> I'm using a Dallas DS2250 at 16 Mhz (8051 clone), but it won't do
> break detect.  I've looked at the 6850, 8251, 7201, 2661, etc...
>
> 	Any help would be appriciated!!!
Actually detecting a BREAK is done by watching for a "character" containing
all zero bits with the framing error resulting from its receipt.  This
means that the line stayed in the zero bit state even past the stop bit
time slot, which basically indicates a BREAK.  There is no special way to
detect BREAK that I have found other than this -- there's no magic signal
generated by UARTs, etc.
Alan Mimms (alan@apple.com, ...!apple!alan)   | My opinions are generally
Portable Macintosh Software Group             | pretty worthless, but
Apple Computer                                | they *are* my own...
Art without engineering is dreaming.  Engineering without art is
calculating.
-- Steven K. Roberts in "Computing Across America"
From: mb4008@cehp11 (Morgan J Bullard)
Subject: Re: Uninterruptible Power Supply
Organization: University of Illinois at Urbana
Lines: 47
alung@megatest.com (Aaron Lung) writes:
>In article <1qk724INN474@hp-col.col.hp.com> cab@col.hp.com (Chris Best) writes:
>>I'm no expert at UPS's, but you said something that made it sound like
>>you didn't realize something.  On a typical UPS (well, on ours, anyway),
>>there is NO switchover from AC to DC.  All the protected equipment is
>>ALWAYS running from the batteries (via an inverter), with the usual
>>condition of also having them on charge.  If the power fails, big deal -
>>the computers never see it (until the batteries start to droop, but
>>there's something like 60 car-sized batteries in that cabinet, so it
>>takes a while).
>>
>>If you were gonna run the guts on straight DC instead of an inverter,
>>why not do it all the time?  Then there'd be no switchover to screw
>>things up, and no having to sense the failure fast.  Just keep the DC
>>on charge when the power is on, and it'll be there in zero time when
>>you "need" it.
>>
>Actually, it's a bit more complicated than that...I sounds to me,
>your UPS takes in AC, rectifies it to DC to charge the batteries, and
>then takes the battery DC and chops it to AC again, feeding your
>equipment.  This approach is the easiest and cleanest way to
>switchover from the mains to battery once your power kicks out since,
>as you mentioned, nothing will know about what happened down the line.
>Another way to do the UPS scheme is to use the mains until you
>lose power, and then kick in the battery backup with it's inverter to
>replace the lost power.  The problem here is the switchover time and
>you've got to resync the AC in no time flat.
That's a standby unit not a UPS, otherwise there would be no interuption.
Many standby units are labled as UPS's though.
Morgan Bullard mb4008@coewl.cen.uiuc.edu
or  mjbb@uxa.cso.uiuc.edu
>Unfortunately, most everything is built around the assumption that
>AC is available, so the UPS guys have to provide and AC output to
>be usable...ya sorta have to make it work with what there already.
>Similar story with our telephone system.  It was first invented back
>in the 1800's.  We're still using the same damn system (media) as they
>did back then.  If I have a phone from back then, I can assure you
>it'll work on today's phone system.  It costs too much to overhaul
>everyone to a new system, so they make it work with what is out there.
>.
From: craw@yoyo.cc.monash.edu.au (Sebastian Filzek)
Subject: IR detector 'cards'???
Summary: IR detector cards..???
Keywords: IR card
Organization: Monash University, Melb., Australia.
Lines: 23
Hi people..
OK heres my problem....
I keep hearing about these little credit card type of things which
detect IR light....
I believe that you have to 'charge them up' under normal (visible) light
and then if they are exposed to IR light they glow or something like
that...
I think that they are avaliable in the states and even in England, but
alas I live in Australia.  Could someone please inform me if I can get
these things over here, and if so where??? and how much???
Also are they really commonly avaliable in the states, and if so, then
how much are they and who sells them (maybe if I cant get one here, I'll
write to one of the companies over seas..)
Anyway.... Thanks in advance...
Sab
93
From: ptorre@hardy.u.washington.edu (Phil Torre)
Subject: Re: Suggestions  on Audio relays ???
Organization: University of Washington, Seattle
Lines: 18
NNTP-Posting-Host: hardy.u.washington.edu
>In article <C5qsBF.IEK@ms.uky.edu> billq@ms.uky.edu (Billy Quinn) writes:
>>I built a little project using the radio shack 5vdc relays to switch
>>audio.  I got pretty bad 'clicks' when the thing switched.
>
>>	Is there a good relay/relay circuit that I can use for switching
>>audio, so that there will be *NO* noise of any kind on the audio lines.
>
I missed the first part of this thread; are you switching line level or
speaker level audio?
If line level, there's a single chip 4x1 *stereo* audio switch available
that switches 4 two-channel inputs into 1 two-channel output, and also
has a mute function, all controllable with ttl inputs.  LM1037, I think?
If speaker level, never mind.  :(
Phil Torre (ptorre@u.washington.edu)
From: franko@cco.caltech.edu (Frank Filipanits)
Subject: Re: arcade style buttons and joysticks
Organization: California Institute of Technology, Pasadena
Lines: 19
NNTP-Posting-Host: alumni.caltech.edu
> > Can anyone tell me where it is possible to purchase controls found
> > on most arcade style games.  Many projects I am working on would
> > be greatly augmented if I could implement them.  Thanx in advance.
>HAP controls just outside Chicago sells these.
>						Andrew MacRae
Actually, it's HAPP, and some of their equipment can be found in the
Parts Express catalog (1-800-338-0531).  They show switches for $2,
joysticks for $13 and trackballs for $80.  They also have pinball parts.
Good luck.
--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Frank Filipanits Jr.    B.S. EE/Music, California Institute of Technology '92
Audio Consultant          M.S. Music Engineering, University of Miami     '94
franko@alumni.caltech.edu   "No, officer, I don't know how fast I was going."
From: rgc3679@bcstec.ca.boeing.com (Robert G. Carpenter)
Subject: Can Radio Freq. Be Used To Measure Distance?
Organization: Boeing Computer Services
Lines: 19
I'm wondering if it's possible to use radio waves to measure the
distance between a transmitter(s) and receiver?
Seems to me that you should be able to measure the signal strength
and determine distance. This would be for short distances (2000 ft),
and I would need to have accuracy of 6 inches, or so.
How about measuring vertical distance as well, any chance - or am I getting
ridiculous?
What frequencies would be best for this? Or does matter?
Sorry if I'm "mucking up" the network with one of those questions best
answered by Bill Willis via US Mail... and I apologize for not being
"tuned-in" to electronics. :-)
R.G. Carpenter, Ph.D., P.E. (sorry... only an ME)
From: pauls@trsvax.tandy.com
Subject: Re: Need source for old Radio Shack ste
Nf-ID: #R:acs.ucalgary.ca:27323:trsvax:288200083:000:125
Nf-From: trsvax.tandy.com!pauls    Apr 21 09:36:00 1993
Lines: 5
It's made by Rohm. (as is all BAxxx parts). Call 714-855-2131 and ask if
you can get a sample (it's only like a $2 part).
From: pauls@trsvax.tandy.com
Subject: Re: Need Info on DSP project
Nf-ID: #R:ee.ualberta.ca:735344986:trsvax:288200082:000:164
Nf-From: trsvax.tandy.com!pauls    Apr 21 09:31:00 1993
Lines: 6
Motorola has a good app note on a 10 band equalizer using a 56000 DSP. It
could be easily ported to an Ariel board, or even a Turtle Beach 56K
development system.
From: kolstad@cae.wisc.edu (Joel Kolstad)
Subject: Re: Can Radio Freq. Be Used To Measure Distance?
Organization: U of Wisconsin-Madison College of Engineering
Lines: 25
In article <C5v13M.C37@bcstec.ca.boeing.com> rgc3679@bcstec.ca.boeing.com (Robert G. Carpenter) writes:
>I'm wondering if it's possible to use radio waves to measure the
>distance between a transmitter(s) and receiver?
Yes, you could.
>Seems to me that you should be able to measure the signal strength
>and determine distance. This would be for short distances (2000 ft),
>and I would need to have accuracy of 6 inches, or so.
Well, letsee (whipping out HP-48SX, soon to be GX): 6 inches/3*10^8 m/s=.5
nanoseconds resolution.  Hmm.  That'll be rather difficult!
The more standard (read: better) method is to use ultrasound, generally
somewhere around 40kHz.  Sound travels a heck of a lot slower than light
(radio waves), and is therefore much easier to deal with.
>What frequencies would be best for this? Or does matter?
It might be easiest to visit a hardware store and look at the numerous
"sonic estimator" type devices that do what you want here.  Many are pretty
cheap too -- <$30.  (In fact, for awhile the Stanley Estimator was selling
for something like $8.  That's the one I bought! :-) )
---Joel Kolstad
From: system@garlic.sbs.com (Anthony S. Pelliccio)
Subject: Re: Beginner's RF ???
Organization: Antone's Italian Kitchen and Excellence in Operating Network
X-Newsreader: rusnews v1.02
Lines: 27
klink@cbnewsl.cb.att.com (steven.r.klinkner) writes:
> Can anybody recommend a good, application-oriented beginner's reference
> to RF circuits?
>
> I am pretty good on theory & know what different types of modulation mean,
> but don't have a lot of practical experience.  A book detailing working
> circuits of different types (modulation, power, frequency, what is legal,
> what is not, et cetera), would be very helpful.
>
> Thanks.
Well, you might try the A.R.R.L.'s license study guides. For example, my
Advanced Class study guide has lots and lots of good RF and electronics
theory in it. I would imagine the other books are good too.
Tony
-----------------------------------------------------------------------
-- Anthony S. Pelliccio, kd1nr/ae    // Yes, you read it right, the  //
-- system @ garlic.sbs.com          // man who went from No-Code    //
-----------------------------------// (Thhhppptt!) to Extra in     //
-- Flame Retardent Sysadmin       // exactly one year!            //
-------------------------------------------------------------------
-- This is a calm .sig! --
--------------------------
From: system@garlic.sbs.com (Anthony S. Pelliccio)
Subject: Re: arcade style buttons and joysticks
Organization: Antone's Italian Kitchen and Excellence in Operating Network
X-Newsreader: rusnews v1.02
Lines: 26
dnewman@lynx.dac.northeastern.edu (David F. Newman) writes:
> Hi there,
> Can anyone tell me where it is possible to purchase controls found
> on most arcade style games.  Many projects I am working on would
> be greatly augmented if I could implement them.  Thanx in advance.
>
> -Dave
> dnewman@lynx.dac.northeastern.edu
>
Contact Chris Arthur at Chris_Arthur@pennies.stratus.com
He restores lots of old video and arcade games and knows where to get
parts.
Tony
-----------------------------------------------------------------------
-- Anthony S. Pelliccio, kd1nr/ae    // Yes, you read it right, the  //
-- system @ garlic.sbs.com          // man who went from No-Code    //
-----------------------------------// (Thhhppptt!) to Extra in     //
-- Flame Retardent Sysadmin       // exactly one year!            //
-------------------------------------------------------------------
-- This is a calm .sig! --
--------------------------
From: jvannes@vms.macc.wisc.edu
Subject: Re: Long distance IR detection
Organization:  University of Wisconsin Academic Computing Center
Distribution:  na
Lines: 26
In article <wb9omc.735430855@dynamo.ecn.purdue.edu>, wb9omc@dynamo.ecn.purdue.edu (Duane P Mantick) writes...
>	BTW, I have seen IRLEDs with outputs up to 6 watts...honest,
>6 WATTS.  I don't have the book here at work so I can't recall the company
>name.  The 6 watter ain't cheap, around $108 but if you want some power,
>mamamia, that's pretty hot.  They also have a 4 watt, a 2 watt and a
>1 watt device in their line, and will sell small quan. to individuals.
>If you are interested, I can find the book at home and get the
>pertinent info.
>
You are probably referring to the products of
Opto Diode Corp.
750 Mitchell Road
Newbury Park Ca 91320
805 499-0335
The make some amazing IRLED's.  The really high-powered devices are arrays of
3, 6, or 9, LED's on a TO-66 header.  The 9-chip model puts out 6.5 Watts in
response to a 5 Amp, 10 uS. pulse at a .5% duty cycle.  I think  these are
designed as illuminators for IR vision systems.
I would also be interested in the application here.  I work with a Dance and
Technology program, and want to build something to track dancers on a 30 foot
wide stage from 50 feet away.
From: mcovingt@aisun1.ai.uga.edu (Michael Covington)
Subject: Re: Radar detector DETECTORS?
Nntp-Posting-Host: aisun1.ai.uga.edu
Organization: AI Programs, University of Georgia, Athens
Lines: 9
There is or was a microwave tower next to Florida's Turnpike, and you
could watch the cars hit the breaks as they came in sight of it every
morning...
--
:-  Michael A. Covington, Associate Research Scientist        :    *****
:-  Artificial Intelligence Programs      mcovingt@ai.uga.edu :  *********
:-  The University of Georgia              phone 706 542-0358 :   *  *  *
:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :  ** *** **  <><
From: rdell@cbnewsf.cb.att.com (richard.b.dell)
Subject: Re: Fujitsu 8" HDD
Keywords: M2321K, M2322K, Fujitsu, Microdisk (-:
Organization: AT&T
Distribution: na
Lines: 15
In article <1993Apr17.204351.2256@aber.ac.uk> cjp1@aber.ac.uk (Christopher John Powell) writes:
[deletions]
>It appears to use two balanced-line connections, but what each connection
>corresponds to I know not. One connection is a 30-way IDC, the other a
>60-way IDC.
Sounds like it is an SMD interface to me, not being at work now
to actually count pins.  there are two varients, SMD  and
SMDC (I think), only minor differences between them.  Widely used
prior to the advent of SCSI for large drives (or all drives) on minis
(and mainframes(?) no experience on those).
Richard Dell
From: hughes@jupiter.ral.rpi.edu (Declan Hughes)
Subject: Manual for Eprom Blower (Logical Devices Prompro-8) Wanted
Nntp-Posting-Host: jupiter.ral.rpi.edu
Organization: Rensselaer Polytechnic Institute, Troy NY
Distribution: usa
Lines: 7
I have an eprom blower made by Logical Devices and the
model name is Prompro-8, but I have lost the manual. Does anyone
have a spare manual that they would like to sell ?
Declan Hughes
hughes@ral.rpi.edu
From: markz@ssc.com (Mark Zenier)
Subject: Re: MC SBI mixer
Article-I.D.: ssc.1993Apr21.183146.19241
Organization: SSC, Inc.,  Seattle, WA
Lines: 17
X-Newsreader: TIN [version 1.1 PL6]
Mark J. Musone (musone@acsu.buffalo.edu) wrote:
: HI, I was wondering if anyone would be able to help me on twwo related
: subjects. I am currently learning about AM/FM receivers and recieving
: circuits.
:
: P.S. any REALLY GOOD BOOKS on AM/FM theory ALONG WITH DETAILED
: ELECTRICAL DIAGRAMS would help a lot.
: I have seen a lot of theory books with no circuits and a lot of
: circuit books with no theory, but one without the other does not help.
A pretty serious book that still seems readable is
Communication Receivers, Principes and Design
by Rohde and Bucher.
Mark Zenier  markz@ssc.wa.com  markz@ssc.com
From: schuch@phx.mcd.mot.com (John Schuch)
Subject: Re: Radio Electronics Free information card
Nntp-Posting-Host: bopper2.phx.mcd.mot.com
Organization: Motorola Computer Group, Tempe, Az.
Lines: 73
In article <C5uLqG.I5@acsu.buffalo.edu> v064mb9k@ubvmsb.cc.buffalo.edu (NEIL B. GANDLER) writes:
>
>	How does the radio Electronics free information cards work.
>Do they just send you some general information about the companies that
>advertise in their magazine or does it also give you sign you up for a
>catalog.
That depends entirely upon the advertiser whose number you circled.
Radio Electronics compiles all of the cards, then each advertiser
gets a computer printout of the names and addresses of all of the readers
who circled their number. Some magazines also provide the data on
self-adhesive labels, and the really big magazines provide the
data on computer disk.
The advertiser decides what to do with the data they get. You will
notice that the Radio Electronics information card (commonly called
a "bingo card" in the industry) includes lines for a company name
and a business phone number. My guess would be that the big, national
advertisers make a distinction between hobbiests and professionals as
best they can. For example, if you include Motorola as your company
and include a business phone (and a mail stop), Tektronics will probably
send you a copy of their hard-bound catalog and have a sales engineer
call you about a week later. If you leave it blank, odds are they
will send you a slick brochure and direct you to a local retail
outlet. Medium and small companies are more likely to send you th
e whole catalog. And then some companies, like Digikey or Jameco, have
nothing to mail out accept the catalog.
A couple of other interesting points about bingo cards: Free, industry
magazines like EDN and such also log your card to their computer. They
use the information at least three ways. They note that you really do read
the magazine and are more likely to continue your subscription or push
you, through repeated mailings, to re-subscribe. They also compile
how many people requested which data for their marketing demographics.
This way thay can tell a prospective advertiser that "23% of readers
requesting data were interested in capacitors." And finally, some
magazines rent lists of readers who request certain information. For
example, Tektronics can rent a list of everyone who requested information
about test equipment OTHER THAN TEKTRONIC's, in the past 6 months.
The other point, in the data the advertiser receives, many magazines
include how many items you circled on the card. If they want, the
advertiser can attempt to cull out the "literature collectors" from
the serious potential customers.
"Can you say qualified sales leads? I thought you could."
What's the BEST way for a hobbiest to deal with bingo cards?
Never circle more than 8 number on the card. If you want more
than 8 items, use the second card and mail it a couple of
weeks later.
If you are really, really serious and you really, really want
the information, CALL THE ADVERTISER AND ASK! This will also
cut about 15 days off the the response time. Virtually
everyone takes a voice on the phone more seriously than data
on a computer printout.
To help insure you keep getting a trade magazine that you're
not really "qualified" for, send in a bingo card at least every
other month and circle two or three numbers.
Include a business name and phone number, even if it's your house.
Advertisers almost never call.
John Schuch
publisher of: The Arizona High-Tech Times
The Arizona Electrical Journal
The Arizona HVAC News
(all of which have bingo cards)
From: kthompso@donald.WichitaKS.NCR.COM (Ken Thompson)
Subject: Re: Cable TVI interference
Keywords: catv cable television tvi
Organization: NCR Corporation Wichita, KS
Lines: 14
victor@inqmind.bison.mb.ca (Victor Laking) writes:
)Do you know what frequencies chanels 17 to 19 use and what is usually
)allocated to those frequencies for broadcast outside of cable?
17 is air comm.
18 is amateur
19 is business and public service
--
Ken Thompson    N0ITL
NCR Corp.  Peripheral Products Division   Disk Array Development
3718 N. Rock Road  Wichita KS 67226   (316)636-8783
Ken.Thompson@wichitaks.ncr.com
From: gcarter@infoserv.com (George Carter)
Subject: Re: Does someone know what is the news group for IEEE.
Reply-To: gcarter@infoserv.com
Distribution: usa
Organization: SFBAC
Lines: 11
X-Newsreader: Helldiver 1.07 (Waffle 1.64)
In <1993Apr19.192953.22874@usl.edu> yxy4145@ucs.usl.edu (Yu Yingbin) writes:
>       yxy4145@usl.edu     Thanks a lot.
ieee.general
and
ieee.announce
are the most frequently used groups.
From: tchannon@black.demon.co.uk (Tim Channon)
Subject: Re: Laser vs Bubblejet?
Reply-To: tchannon@black.demon.co.uk
Distribution: world
X-Mailer: cppnews $Revision: 1.20 $
Organization: null
Lines: 53
Here is a different viewpoint.
> FYI:  The actual horizontal dot placement resoution of an HP
> deskjet is 1/600th inch.  The electronics and dynamics of the ink
> cartridge, however, limit you to generating dots at 300 per inch.
> On almost any paper, the ink wicks more than 1/300th inch anyway.
>
> The method of depositing and fusing toner of a laster printer
> results in much less spread than ink drop technology.
In practice there is little difference in quality but more care is needed
with inkjet because smudges etc. can happen.
> It doesn't take much investigation to see that the mechanical and
> electronic complement of a laser printer is more complex than
> inexpensive ink jet printers.  Recall also that laser printers
> offer a much higher throughput:  10 ppm for a laser versus about 1
> ppm for an ink jet printer.
A cheap laser printer does not manage that sort of throughput and on top of
that how long does the _first_ sheet take to print? Inkjets are faster than
you say and in both cases the computer often has trouble keeping up with the
printer. (I have a 486/33 and a lot of drivers cannot keep up with the
printer)
A sage said to me: "Do you want one copy or lots of copies?", "One",
"Inkjet".
> Something else to think about is the cost of consumables over the
> life of the printer.  A 3000 page yield toner cartridge is about
> $US 75-80 at discount while HP high capacity (~500-1000 page yield)
> cartridges are about $US 22 at discount.  It could be that over the
> life cycle of the printer that consumables for laser printers are
> less than ink jet printers.  It is getting progressively closer
> between the two technologies.  Laser printers are usually desinged
> for higher duty cycles in pages per month and longer product
> replacement cycles.
Paper cost is the same and both can use refills. Long term the laserprinter
will need some expensive replacement parts (consumables) and on top of that
are the amortisation costs which favour the lowest purchase cost printer.
HP inkjets understand PCL so in many cases a laserjet driver will work if the
software package has no inkjet driver.
There is one wild difference between the two printers: a laserprinter is a
page printer whilst an inkjet is a line printer. This means that a
laserprinter can rotate graphic images whilst an inkjet cannot. Few drivers
actually use this facility.
(there is also the matter of downloadable fonts and so on)
TC.
E-mail: tchannon@black.demon.co.uk or tchannon@cix.compulink.co.uk
From: bed@intacc.uucp (Deb Waddington)
Subject: INFO NEEDED: Gaucher's Disease
Distribution: Everywhere
Expires: 01 Jun 93
Reply-To: bed@intacc.UUCP (Deb Waddington)
Organization: Matrix Artists' Network
Lines: 33
I have a 42 yr old male friend, misdiagnosed as having
osteopporosis for two years, who recently found out that his
illness is the rare Gaucher's disease.
Gaucher's disease symptoms include: brittle bones (he lost 9
inches off his hieght); enlarged liver and spleen; internal
bleeding; and fatigue (all the time). The problem (in Type 1) is
attributed to a genetic mutation where there is a lack of the
enzyme glucocerebroside in macrophages so the cells swell up.
This will eventually cause death.
Enyzme replacement therapy has been successfully developed and
approved by the FDA in the last few years so that those patients
administered with this drug (called Ceredase) report a remarkable
improvement in their condition. Ceredase, which is manufactured
by biotech biggy company--Genzyme--costs the patient $380,000
per year. Gaucher's disease has justifyably been called "the most
expensive disease in the world".
NEED INFO:
I have researched Gaucher's disease at the library but am relying
on netlanders to provide me with any additional information:
**news, stories, reports
**people you know with this disease
**ideas, articles about Genzyme Corp, how to get a hold of
enough money to buy some, programs available to help with
costs.
**Basically ANY HELP YOU CAN OFFER
Thanks so very much!
Deborah
From: mcdonald@aries.scs.uiuc.edu (J. D. McDonald)
Subject: Re: jiggers
Article-I.D.: aries.mcdonald.895.734049502
Organization: UIUC SCS
Lines: 13
In article <78846@cup.portal.com> mmm@cup.portal.com (Mark Robert Thorson) writes:
>This wouldn't happen to be the same thing as chiggers, would it?
>A truly awful parasitic affliction, as I understand it.  Tiny bugs
>dig deeply into the skin, burying themselves.  Yuck!  They have these
>things in Oklahoma.
Close. My mother comes from Gainesville Tex, right across the border.
They claim to be the chigger capitol of the world, and I believe them.
When I grew up in Fort Worth it was bad enough, but in Gainesville
in the summer an attack was guaranteed.
Doug McDonald
From: fulk@cs.rochester.edu (Mark Fulk)
Subject: Re: Breech Baby Info Needed
Organization: University of Rochester
Lines: 89
In article <1993Apr5.151818.27409@trentu.ca> xtkmg@trentu.ca (Kate Gregory) writes:
>In article <1993Apr3.161757.19612@cs.rochester.edu> fulk@cs.rochester.edu (Mark Fulk) writes:
>>
>>Another uncommon problem is maternal hemorrhage.  I don't remember the
>>incidence, but it is something like 1 in 1,000 or 10,000 births.  It is hard
>>to see how you could handle it at home, and you wouldn't have very much time.
>>
>>thing you might consider is that people's risk tradeoffs vary.  I consider
>>a 1/1,000 risk of loss of a loved one to require considerable effort in
>>the avoiding.
>
>Mark, you seem to be terrified of the birth process
That's ridiculous!
>and unable to
>believe that women's bodies are actually designed to do it.
They aren't designed, they evolved.  And, much as it discomforts us, in
humans a trouble-free birth process was sacrificed to increased brain and
cranial size.  Wild animals have a much easier time with birth than humans do.
Domestic horses and cows typically have a worse time.  To give you an idea:
my family tree is complicated because a few of my pioneer great-great-
grandfathers had several wives, and we never could figure out which wife
had each child.  One might ask why this happened.  My great-great-
grandfathers were, by the time they reached their forties, quite prosperous
farmers.  Nonetheless, they lost several wives each to the rigors of
childbirth; the graveyards in Spencer, Indiana, and Boswell, North Dakota,
contain quite a few gravestones like "Ida, wf. of Jacob Liptrap, and
baby, May 6, 1853."
>You wanted
>to section all women carrying breech in case one in a hundred or a
>thousand breech babies get hung up in second stage,
More like one in ten.  And the consequences can be devastating; I have
direct experience of more than a dozen victims of a fouled-up breech birth.
>and now you want
>all babies born in hospital based on a guess of how likely maternal
>hemorrhage is and a false belief that it is fatal.
It isn't always fatal.  But it is often fatal, when it happens out of
reach of adequate help.  More often, it permanently damages one's health.
Clearly women's bodies _evolved_ to give birth (I am no believer in divine
design); however, evolution did not favor trouble-free births for humans.
>You have your kids where you want. You encourage your wife to
>get six inch holes cut through her stomach muscles, expose herself
>to anesthesia and infection, and whatever other "just in case" measures
>you think are necessary.
My, aren't we wroth!  I haven't read a more outrageous straw man attack
in months!  I can practically see your mouth foam.
We're statistically sophisticated enough to balance the risks.  Although
I can't produce exact statistics 5 years after the last time we looked
them up, rest assured that we balanced C-section risks against other risks.
I wouldn't encourage my wife to have a Caesarean unless it was clearly
indicated; on the other hand, I am opposed (on obvious grounds) to waiting
until an emergency to give in.
And bear this in mind: my wife took the lead in all of these decisions.
We talked things over, and I did a lot of the leg work, but the main
decisions were really hers.
>But I for one am bothered by your continued
>suggestions, especially to the misc.kidders pregnant for the first
>time, that birth is dangerous, even fatal, and that all these
>unpleasant things are far better than the risks you run just doing
>it naturally.
I don't know of very many home birth advocates, even, that think that
a first-time mother should have her baby at home.
>I'm no Luddite. I've had a section. I'm planning a hospital birth
>this time. But for heaven's sake, not everyone needs that!
But people should bother to find out the relative risks.  My wife was
unwilling to take any significant risks in order to have nice surroundings.
In view of the intensity of the birth experience, I doubt surroundings
have much importance anyway.  Somehow the values you're advocating seem
all lopsided to me: taking risks, even if fairly small, of serious
permanent harm in order to preserve something that is, after all,
an esthetic consideration.
--
Mark A. Fulk			University of Rochester
Computer Science Department	fulk@cs.rochester.edu
From: Lawrence Curcio <lc2b+@andrew.cmu.edu>
Subject: Analgesics with Diuretics
Organization: Doctoral student, Public Policy and Management, Carnegie Mellon, Pittsburgh, PA
Lines: 6
NNTP-Posting-Host: po2.andrew.cmu.edu
I sometimes see OTC preparations for muscle aches/back aches that
combine aspirin with a diuretic. The idea seems to be to reduce
inflammation by getting rid of fluid. Does this actually work?
Thanks,
-Larry C.
From: uabdpo.dpo.uab.edu!gila005 (Stephen Holland)
Subject: Re: Lactose intolerance
Organization: Gastroenterology - Univ of Alabama
Lines: 19
In article <ng4.733990422@husc.harvard.edu>, ng4@husc11.harvard.edu (Ho
Leung Ng) wrote:
>
>
>    When I was a kid in primary school, I used to drink tons of milk without
> any problems.  However, nowadays, I can hardly drink any at all without
> experiencing some discomfort.  What could be responsible for the change?
>
> Ho Leung Ng
> ng4@husc.harvard.edu
You became older and your intestine normalized to the weaned state.  That
is, lactose tolerance is an unusual state for adults of most mammals
except for h. sapiens of northern European origin.  As a h. sapiens of
asian descent (assumption based on name) the loss of lactase is normal
for you.
Steve Holland
gila005@uabdpo.dpo.uab.edu
From: bennett@kuhub.cc.ukans.edu
Subject: Smoker's Lungs
Organization: University of Kansas Academic Computing Services
Lines: 3
How long does it take a smoker's lungs to clear of the tar after quitting?
Does your chances of getting lung cancer decrease quickly or does it take
a considerable amount of time for that to happen?
From: dougb@comm.mot.com (Doug Bank)
Subject: Re: Blood Cholesterol -  Gabe Mirkin's advice
Reply-To: dougb@ecs.comm.mot.com
Organization: Motorola Land Mobile Products Sector
Nntp-Posting-Host: 145.1.146.35
Lines: 29
In article <1pka0uINNnqa@mojo.eng.umd.edu>, georgec@eng.umd.edu (George B. Clark) writes:
|> Forget about total cholesterol when assessing health risk factors.
|> Instead, use a relationship between LDL and HDL cholesterol:
|>
|> If your LDL is       You need an HDL of at least
|>
|>       90                 35
|>      100                 45
|>      110                 50
|>      120                 55
|>      130                 60
|>      140                 70
Gee, what do I do?  My LDL is only 50-60. (and my HDL is only 23-25)
I must be risking something, but Is it the same risk as those with
very high LDL?
|> If your triglycerides are above 300, and your HDL is below 30, the
|> drug of choice is gemfibrozil (Lopid) taken as a 600mg tablet
|> thirty minutes before your morning and evening meals.
What about exercise and a low-fat diet?  What are the long-term
effects of this drug?
--
Doug Bank                       Private Systems Division
dougb@ecs.comm.mot.com          Motorola Communications Sector
dougb@nwu.edu                   Schaumburg, Illinois
dougb@casbah.acns.nwu.edu       708-576-8207
From: cliff@buster.stafford.tx.us (Cliff Tomplait)
Subject: Re: sex problem.
Organization: Buster irby
Lines: 34
ls8139@albnyvms.bitnet (larry silverberg) writes:
>I have question that I hope is taken seriously, despite the subject content.
>Problem:  My long time girlfriend lately has not been initiating any sexual
>	activity.  For the last four months things have changed dramatically.
>       ...
>	--to make this shorter-- Summary: nothing that I can think of has
>				changed....
>       ...
>She suggested we go to a sex counselor, but I really don't want to (just yet).
>Any suggestions would be appreciated.
>If you think you can help me, please contact me by e-mail for further info.
>PLEASE serious replies only.
>Thanks, Larry
Larry:
The subject content IS serious; as is the question.
On one hand you state that "things have changed dramatically" but, at the
same time nothing you "can think of has changed".  Your girlfriend seems
to want to see a counselor, but you don't.
I'd recommend that you examine your hesitation to see a counselor.  It's
a very good environment to examine issues.
The fact of the matter is:  your girlfriend has a different perception than
you.  The TWO of you need to address the issue in order to resolve it.
Please consider going to a counselor with your girlfriend.  What could it
possibly hurt?
Cliff  (the paramedic)
From: uabdpo.dpo.uab.edu!gila005 (Stephen Holland)
Subject: Re: Prednisone...what are the significant long term side effects?
Organization: Gastroenterology - Univ of Alabama
Lines: 30
> >I have been taking prednisone 5mg twice a day for a while to control
> >Ulcerative Colitis. It seems like if I reduce the dosage, the problem
> >becomes worse. At this point, i see myself taking prednisone for a long
> >long time, perhaps for ever. I was wondering about long term major side
> >effects, things like potential birth defects, arthritis etc. I have been
> >putting on weight, my face looks puffed and round, experience sudden mood
> >swings. As I understand, these are all short term.
I second what Spenser Aden said in reply.  Additionally, it is hard to say
what type of response you ar3e having to prednisone since you did not say
how long you have been on it.  Patients are generally kept on steroids for
months before thinking about tapering.  Alternatives to daily dosing are
every other day dosing, in your case 20mg every other day would be a start.
Another option if it is not possible to get you off prednisone is to start
azathioprine.  Like Spenser said, you should generally be on another drug
in addition to your prednisone, like asulfidine.  A lot of the specifics
about options, though, depends on severity, location, and duration of
disease, as well as histology, so take advice off the net for what it
is worth.
I treat patients with UC and Crohn's.  An educated patient is a good
patient, but let your doctor know where the advice came from so things
can be put in context.  You should also be a member of the Crohn's and
Colitis Foundation of America.  1-800-932-2423 office / 1-800-343-3637
info hotline.
Best of Luck to you.
Steve Holland.
gila005@uabdpo.dpo.uab.edu
From: nyeda@cnsvax.uwec.edu (David Nye)
Subject: Re: Mental Illness
Organization: University of Wisconsin Eau Claire
Lines: 13
[reply to dabbott@augean.eleceng.adelaide.edu.AU (Derek Abbott)]
>Are there any case histories of severe mental illness cases remarkably
>recovering after a tragic accident or trauma (eg. through nobody's fault,
>being trapped in a fire and losing your legs, say)?
I know of a patient who was severely and chronically depressed and tried
to kill himself with a bullet to the temple.  He essentially gave
himself a prefrontal lobotomy, curing the depression.
David Nye (nyeda@cnsvax.uwec.edu).  Midelfort Clinic, Eau Claire WI
This is patently absurd; but whoever wishes to become a philosopher
must learn not to be frightened by absurdities. -- Bertrand Russell
From: nyeda@cnsvax.uwec.edu (David Nye)
Subject: Re: Can't Breathe
Organization: University of Wisconsin Eau Claire
Lines: 15
[reply to ron.roth@rose.com (ron roth)]
>While you're right that the S vertebrae are attached to each other,
>the sacrum, to my knowledge, *can* be adjusted either directly, or
>by applying pressure on the pubic bone...
Ron, you're an endless source of misinformation!  There ARE no sacral
vertebrae.  There is a bone called the sacrum at the end of the spine.
It is a single, solid bone except in a few patients who have a
lumbarized S1 as a normal variant.  How do you adjust a solid bone,
break it?  No, don't tell me, I don't want to know.
David Nye (nyeda@cnsvax.uwec.edu).  Midelfort Clinic, Eau Claire WI
This is patently absurd; but whoever wishes to become a philosopher
must learn not to be frightened by absurdities. -- Bertrand Russell
From: rousseaua@immunex.com
Subject: Re: Lactose intolerance
Organization: Immunex Corporation, Seattle, WA
Lines: 8
In article <ng4.733990422@husc.harvard.edu>, ng4@husc11.harvard.edu (Ho Leung Ng) writes:
>
>    When I was a kid in primary school, I used to drink tons of milk without
> any problems.  However, nowadays, I can hardly drink any at all without
> experiencing some discomfort.  What could be responsible for the change?
>
> Ho Leung Ng
> ng4@husc.harvard.edu
From: rousseaua@immunex.com
Subject: Re: Lactose intolerance
Organization: Immunex Corporation, Seattle, WA
Lines: 27
In article <1993Apr5.165716.59@immunex.com>, rousseaua@immunex.com writes:
> In article <ng4.733990422@husc.harvard.edu>, ng4@husc11.harvard.edu (Ho Leung Ng) writes:
>>
>>    When I was a kid in primary school, I used to drink tons of milk without
>> any problems.  However, nowadays, I can hardly drink any at all without
>> experiencing some discomfort.  What could be responsible for the change?
>>
>> Ho Leung Ng
>> ng4@husc.harvard.edu
OOPS. My original message died. I'll try again...
I always understood (perhaps wrongly...:)) that the bacteria in our digestive
tracts help us break down the components of milk. Perhaps the normal flora of
the intestine changes as one passes from childhood.
Is there a pathologist or microbiologist in the house?
Anne-Marie Rousseau
e-mail: rousseaua@immunex.com
(Please note that these opinions are mine, and only mine.)
From: kxgst1+@pitt.edu (Kenneth Gilbert)
Subject: Re: Smoker's Lungs
Article-I.D.: blue.7934
Organization: University of Pittsburgh
Lines: 21
In article <1993Apr5.123315.48837@kuhub.cc.ukans.edu> bennett@kuhub.cc.ukans.edu writes:
>How long does it take a smoker's lungs to clear of the tar after quitting?
>Does your chances of getting lung cancer decrease quickly or does it take
>a considerable amount of time for that to happen?
The answer to your first question is rather difficult to answer without
doing a lot of autopsies.  The second question is something that's been
known for some time.  It appears that within about 15 years of quitting
smoking a person's risk for developing lung cancer drops to that of the
person who never smoked (assuming you do not get lung cancer in the
interim!).  The risk to someone who smoked the equivalent of a pack per
day for 40 years is around 20 times as high as a non-smoker.  Still
rather low overall, but significant.  Personally, I'd be more concerned
about heart disease secondary to smoking -- it's much more common, and
even a small increase in risk is significant there.
--
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-|-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
=  Kenneth Gilbert              __|__        University of Pittsburgh   =
=  General Internal Medicine      |      "...dammit, not a programmer!  =
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-|-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
From: kxgst1@pitt.edu (Kenneth Gilbert)
Subject: Re: Can't Breathe
Article-I.D.: blue.7936
Lines: 23
X-Newsreader: TIN [version 1.1 PL8]
David Nye (nyeda@cnsvax.uwec.edu) wrote:
: [reply to ron.roth@rose.com (ron roth)]
:
: >While you're right that the S vertebrae are attached to each other,
: >the sacrum, to my knowledge, *can* be adjusted either directly, or
: >by applying pressure on the pubic bone...
:
: Ron, you're an endless source of misinformation!  There ARE no sacral
: vertebrae.  There is a bone called the sacrum at the end of the spine.
: It is a single, solid bone except in a few patients who have a
: lumbarized S1 as a normal variant.  How do you adjust a solid bone,
: break it?  No, don't tell me, I don't want to know.
:
Oh come now, surely you know he only meant to measure the flow of
electromagnetic energy about the sacrum and then adjust these flows
with a crystal of chromium applied to the right great toe.  Don't
you know anything?
--
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-|-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
=  Kenneth Gilbert              __|__        University of Pittsburgh   =
=  General Internal Medicine      |      "...dammit, not a programmer!  =
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-|-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
From: euclid@mrcnext.cso.uiuc.edu (Euclid K.)
Subject: Re: Anti-Viral Herbs
Article-I.D.: news.C51o24.8A4
Distribution: na
Organization: University of Illinois at Urbana
Lines: 38
kxgst1+@pitt.edu (Kenneth Gilbert) writes:
>Unfortunately it was rather poorly researched, and would not be available
>today if it were just invented.  Keep in mind however that those were
>the days when a bottle of Coca Cola really did contain coca extract and
>a certain amount of active cocaine.  Times have changed, and our attitudes
>need to change with them.
Well, yes.  That was a part of my point.  Aspirin has its problems, but
in some situations it is useful.  Ditto stuff like licorice root.  Taking
anything as a drug for theraputic purposes implicitly carries the idea
of taking a dose where the benefits are not exceeded by any unwanted,
additional effects.  Taking any drug when the potential ill-effects are
not known is a risk assumed by the parties involved, and it may be that
in a given situation the risk is worthwhile.
Like Prozac, for instance; Prozac has been shown to be theraputic in
some cases where the tri-cyclics fail.  But Prozac hasn't been in use
that long, and it really isn't clear what if any effects it may have
when taken over long periods of time, even though it has been tested
by present day standards.  Should Prozac be taken off the market because
long-term effects, if any, are not known?  IMHO, i'd say no.
euclid
>=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
>=  Kenneth Gilbert                |          University of Pittsburgh   =
>=  General Internal Medicine    --*--        Pittsburgh, PA             =
>=  kxgst1+@pitt.edu               |      "...dammit, not a programmer!  =
>=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
>--
>=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
>=  Kenneth Gilbert                |          University of Pittsburgh   =
>=  General Internal Medicine    --*--        Pittsburgh, PA             =
>=  kxgst1+@pitt.edu               |      "...dammit, not a programmer!  =
--
Euclid K.       standard disclaimers apply
"It is a bit ironic that we need the wave model [of light] to understand the
propagation of light only through that part of the system where it leaves no
trace."  --Hudson & Nelson (_University_Physics_)
From: jfare@53iss6.Waterloo.NCR.COM (Jim Fare)
Subject: ringing ears
Keywords: ringing ears, sleep, depression
Reply-To: jfare@53iss6.Waterloo.NCR.COM (Jim Fare)
Distribution: world
Organization: Imaging Systems Division, NCR Corp, Waterloo, Ont., CANADA
Lines: 15
A friend of mine has a trouble with her ears ringing.  The ringing is so loud
that she has great difficulty sleeping at night.  She says that she hasn't
had a normal night's sleep in about 6 months (she looks like it too :-().
This is making her depressed so her doctor has put her on anti-depressants.
The ringing started rather suddenly about 6 months ago.  She is quickly losing
sleep, social life and sanity over this.
Does anyone know of any treatments for this?  Any experience?  Coping
mechanisms?  Any opinions on the anti-depressant drugs?
[J.F.]
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Subject: Re: Twitching eyelid
Summary: Different cause
Nntp-Posting-Host: aisun3.ai.uga.edu
Organization: AI Programs, University of Georgia, Athens
Lines: 9
I'm surprised nobody mentioned that twitching of the eyelid can be a
symptom of an infection, especially if it also itches or stings.
(It happened to me, and antibiotic eyedrops cleared it up nicely.)
--
:-  Michael A. Covington         internet mcovingt@ai.uga.edu :    *****
:-  Artificial Intelligence Programs       phone 706 542-0358 :  *********
:-  The University of Georgia                fax 706 542-0349 :   *  *  *
:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :  ** *** **
From: dyer@spdcc.com (Steve Dyer)
Subject: Re: fibromyalgia
Organization: S.P. Dyer Computer Consulting, Cambridge MA
In article <93Apr5.133521edt.1231@smoke.cs.toronto.edu> craig@cs.toronto.edu (Craig MacDonald) writes:
>>  It may be extremely
>>common, something like 5% of the population.  It is treatable with
>>tricyclic antidepressant-type drugs (Elavil, Pamelor).
>
>Why is it treated with antidepressants?  Is it considered a
>psychogenic condition?
No.  That these drugs happen to be useful as antidepressants is neither
here nor there.
--
Steve Dyer
dyer@ursa-major.spdcc.com aka {ima,harvard,rayssd,linus,m2c}!spdcc!dyer
From: dyer@spdcc.com (Steve Dyer)
Subject: Re: Analgesics with Diuretics
Organization: S.P. Dyer Computer Consulting, Cambridge MA
In article <ofk=lve00WB2AvUktO@andrew.cmu.edu> Lawrence Curcio <lc2b+@andrew.cmu.edu> writes:
>I sometimes see OTC preparations for muscle aches/back aches that
>combine aspirin with a diuretic.
You certainly do not see OTC preparations advertised as such.
The only such ridiculous concoctions are nostrums for premenstrual
syndrome, ostensibly to treat headache and "bloating" simultaneously.
They're worthless.
>The idea seems to be to reduce
>inflammation by getting rid of fluid. Does this actually work?
That's not the idea, and no, they don't work.
--
Steve Dyer
dyer@ursa-major.spdcc.com aka {ima,harvard,rayssd,linus,m2c}!spdcc!dyer
From: jmilhoan@magnus.acs.ohio-state.edu (JT)
Subject: Re: ringing ears
Keywords: ringing ears, sleep, depression
Nntp-Posting-Host: bottom.magnus.acs.ohio-state.edu
Organization: The Ohio State University
Lines: 50
In article <10893@ncrwat.Waterloo.NCR.COM> jfare@53iss6.Waterloo.NCR.COM (Jim Fare) writes:
>
>
>A friend of mine has a trouble with her ears ringing.  The ringing is so loud
>that she has great difficulty sleeping at night.  She says that she hasn't
>had a normal night's sleep in about 6 months (she looks like it too :-().
>This is making her depressed so her doctor has put her on anti-depressants.
Sometimes I have a problem with doctor's prescribing medicine like
this.  I of course don't know the exact situation, and
anti-depressants may work, but it isn't helping the ringing at all, is it?
>The ringing started rather suddenly about 6 months ago.  She is quickly losing
>sleep, social life and sanity over this.
Mine started about three years back.  Turns out I have tinnitus
bilateral (translation: ringing in both ears, basically ;).  If this
is what it is, she'll probably get used to it.  It would keep me up
and drive me nuts too, but nowadays, I have to plug both my ears with
my fingers to check to see if they are ringing.  Usually they are, but
you get so used to it, it just gets tuned out.  Yes, this is what I've
read about it... not just from my own personal experience.
>Does anyone know of any treatments for this?  Any experience?  Coping
>mechanisms?  Any opinions on the anti-depressant drugs?
Millions have it, according to my physician.  You just learn to cope
with it (like I mentioned earlier) by ignoring it.  It eventually
becomes unconscious.
The doc also said it could be caused by diet (ie: too much caffeine)
and stress, but I haven't changed my lifestyle much, and it just comes
and goes (it is always there somewhat, but now I rarely notice it when
it really "kicks in").
Also, it doesn't necessarily mean there is any hearing loss, either
caused by it or causing it.  I had an ENT (ear/nose/throat) exam, and
passed.  In fact, my hearing is quite good considering I don't take as
good of care of my hearing as I should.
Her reaction is normal.  If it is tinnitus, chances are good she'll
begin to not even notice it.
This info is taken mostly from a few "experts", my own experience, and
some readings (sorry, it was a few years back and don't have any
specifics handy).
JT
From: amigan@cup.portal.com (Mike - Medwid)
Subject: Emphysema question
Organization: The Portal System (TM)
Distribution: na
Lines: 14
A friend of mine is going in later this week for tests to see if has
emphysema.  His lung capacity has decreased over time.  His father died
of the disease.  He works in woodworking.  I believe he has a very
occasional cigarette, perhaps one cigarette a day or even less.  He tells
me this..I've never seen him light up.  He has some pretty healthy
life style habits, good diet, exercise, meditation, retreats, therapy
etc.  Anyhow..he is very concerned with this check up.  I know really
nothing about the disease.  I believe it interferes with the lining
of the lung being able to exchange oxygen.
Is a diagnosis of emphysema a death sentence?  If he were to give up smoking
entirely would that better his chances for recovery?  What are some
modern therapies used in people with this disease?  I would appreciate
any information.  Thanks.  amigan@cup.portal.com
From: jfare@53iss6.Waterloo.NCR.COM (Jim Fare)
Subject: Re: Oily skin - problem?
Reply-To: jfare@53iss6.Waterloo.NCR.COM (Jim Fare)
Distribution: world
Organization: Imaging Systems Division, NCR Corp, Waterloo, Ont., CANADA
Lines: 15
In article <1993Apr5.044140.1@vaxc.stevens-tech.edu> u92_hwong@vaxc.stevens-tech.edu writes:
>	I have a very oily skin.  My problem is when I wash my face, it becomes
>oily in half an hour.  Especially in the nose region.  Is this an illness?  How
>can I prevent it from occuring in such short time?  Is there a cleanser out
>there that will do a better job -- that is after cleaning, my face won't become
>oily in such a short time.
I don't think that's a problem.  My face is quite oily too.  I had a moderate
acne problem for many years.  I then found that if I vigorously scrub my face
with a nail brush and soap (Irish Spring) twice a day the acne was not a
problem.  I can still leave a pretty health nose print on a mirror after 45 min
(don't ask ;->) but acne is not a real problem anymore.
[J.F.]
From: jim.zisfein@factory.com (Jim Zisfein)
Subject: Re: Migraines and scans
Distribution: world
Organization: Invention Factory's BBS - New York City, NY - 212-274-8298v.32bis
Reply-To: jim.zisfein@factory.com (Jim Zisfein)
Lines: 37
DN> From: nyeda@cnsvax.uwec.edu (David Nye)
DN> A neurology
DN> consultation is cheaper than a scan.
And also better, because a neurologist can make a differential
diagnosis between migraine, tension-type headache, cluster, benign
intracranial hypertension, chronic paroxysmal hemicrania, and other
headache syndromes that all appear normal on a scan.  A neurologist
can also recommend a course of treatment that is appropriate to the
diagnosis.
DN> >>Also, since many people are convinced they have brain tumors or other
DN> >>serious pathology, it may be cheaper to just get a CT scan then have
DN> >>them come into the ER every few weeks.
DN> And easier than taking the time to reassure the patient, right?
DN> Personally, I don't think this can ever be justified.
Sigh.  It may never be justifiable, but I sometimes do it.  Even
after I try to show thoroughness with a detailed history, neurologic
examination, and discussion with the patient about my diagnosis,
salted with lots of reassurance, patients still ask "why can't you
order a scan, so we can be absolutely sure?"  Aunt Millie often gets
into the conversation, as in "they ignored Aunt Millie's headaches
for years", and then she died of a brain tumor, aneurysm, or
whatever.  If you can get away without ever ordering imaging for a
patient with an obviously benign headache syndrome, I'd like to hear
what your magic is.
Every once in a while I am able to bypass imaging by getting an EEG.
Mind you, I don't think EEG is terribly sensitive for brain tumor,
but the patient feels like "something is being done" (as if the
hours I spent talking with and examining the patient were
"nothing"), the EEG has no ionizing radiation, it's *much* cheaper
than CT or MRI, and the EEG brings in some money to my department.
---
. SLMR 2.1 . E-mail: jim.zisfein@factory.com (Jim Zisfein)
From: jim.zisfein@factory.com (Jim Zisfein)
Subject: Re: migraine and exercise
Distribution: world
Organization: Invention Factory's BBS - New York City, NY - 212-274-8298v.32bis
Reply-To: jim.zisfein@factory.com (Jim Zisfein)
Lines: 29
JL> From: jlecher@pbs.org
JL> > I would not classify a mild headache that was continuous for weeks
JL> > as migraine, even if the other typical features were there (e.g.,
JL> > unilateral, nausea and vomiting, photophobia).  Migraines are, by
JL> > common agreement, episodic rather than constant.
JL> >
JL> Well, I'm glad that you aren't my doctor, then, or I'd still be suffering.
JL> Remember, I was tested for any other cause, and there was nothing. I'm
JL> otherwise very healthy.
JL> The nagging pain has all of the qualifications: it's on one side, and
JL> frequently included my entire right side: right arm, right leg, right eye,
JL> even the right side of my tongue hurt or tingled. Noise hurt, light hurt,
JL> thinking hurt. When it got bad, I would lose my ability to read.
The differential diagnosis between migraine and non-migranous pain
is not *always* important, because some therapies are effective in
both (e.g., tricyclic antidepressants such as amitriptyline,
non-steroidal anti-inflammatory drugs such as ibuprofen).  Other
therapies may be more specific: beta-blockers such as propranolol
work better in migraine than tension-type headache.
The most important thing, from your perspective, is that you got
relief.  Also, please understand that a diagnosis other than
migraine does not necessarily mean "psychogenic"; I suspect that
organic factors play as large a role in tension-type headache as in
migraine.
---
. SLMR 2.1 . E-mail: jim.zisfein@factory.com (Jim Zisfein)
From: julkunen@messi.uku.fi (Antero Julkunen)
Subject: What about sci.med.chemistry
Organization: University of Kuopio, Finland
Lines: 10
There is this newsgroup sci.med.physics and there has been quite a lot
discussion in this group about many chemical items e.g. prolactin
cholesterol, TSH etc. Should there also be a newsgroup sci.med.chemistry?
--
Antero Julkunen, Dept Clinical Chemistry, University of Kuopio, Finland
e-mail: julkunen@messi.uku.fi, phone +358-71-162680, fax +358-71-162020
From: kturner@copper.denver.colorado.edu (Kathleen J Turner)
Subject: Mystery Illness with eye problems
Organization: University of Colorado at Denver
Lines: 29
A friend has the following symptoms which have occurred periodically
every few months for the last 3 years.  An episode begins with extreme
tiredness followed by:
1. traveling joint pains and stiffness affecting mostly the elbows,
knees, and hips.
2. generalized muscle pains
3. tinnitus and a feeling of pressure in her ears
4. severe sweating occuring both at night and during the day
5. hemorrhaging in both eyes.  Her opthamologist calls it peripheral
retinal hemorhages and says it looks similar to diabetic retinopathy.  (She
isn't diabetic--they checked.
6. distorted color vision and distorted vision in general (telephone
poles do not appear to be straight)
7. loss of peripheral vision.
Many tests have been run and all are normal except for something
called unidentified bright objects found on a MRI of her brain.  The only
thing that seems to alleviate one of these episodes is prednisone.  At
times she had been on 60 mg per day.  Whenever she gets down to 10-15 mg
the symptoms become acute again.
She is quite concerned because the retinal hemorrhages are becoming
worse with each episode and her vision is suffering.  None of the docs she
has seen have any idea what this condition is or what can be done to stop
it.  Any suggestions or advice would be greatly appreciated. Thanks in
advance.  Kathy Turner
From: caf@omen.UUCP (Chuck Forsberg WA7KGX)
Subject: Re: My New Diet --> IT WORKS GREAT !!!!
Organization: Omen Technology INC, Portland Rain Forest
Lines: 34
In article <1993Apr5.191712.7543@inmet.camb.inmet.com> mazur@bluefin.camb.inmet.com (Beth Mazur) writes:
>In <1993Apr03.1.6627@omen.UUCP> caf@omen.UUCP (Chuck Forsberg WA7KGX) writes:
>>Gordon, your experience is valid for many, but not all.  The
>>fact that you know a few people who have been overweight and are
>>now stable at a lower (normal or just less?) weight does not
>>contradict the observation that only 5-10 per cent can maintain
>>ideal weight with current technology.
>
>Actually, the observation is that only 5-10% of those who seek help
>from your so-called "diet evangelists" can maintain their weight.  I
>happen to agree with Keith Lynch that there are many people who can
>and do lose weight on their own, and who are not reflected in the
>dismal failure rate that is often quoted.
>
>Wasn't there a study where a researcher asked a more general population,
>perhaps some part of a university community, about weight loss and he/she
>found that a much higher percentage had lost and maintained?
In fact Adiposity 101 mentions a similar study (search for "life
events" in any recent version of Adiposity 101).
The problem with anecdotal reports about individuals who have
lost weight and kept it off is that we don't know what caused
the weight gain in the first place.  This is critical because
someone who gains weight because of something temporary (drug
effect, life event, etc.) may appear successful at dieting when
the weight loss was really the result of reversing the temporary
condition that caused the weight gain.
--
Chuck Forsberg WA7KGX          ...!tektronix!reed!omen!caf
Author of YMODEM, ZMODEM, Professional-YAM, ZCOMM, and DSZ
Omen Technology Inc    "The High Reliability Software"
17505-V NW Sauvie IS RD   Portland OR 97231   503-621-3406
From: swkirch@sun6850.nrl.navy.mil (Steve Kirchoefer)
Subject: Re: Can't Breathe
Article-I.D.: ra.C526Hv.LCL
Organization: Naval Research Laboratory  (Electronics Science and Technology Division)
Lines: 17
Getting back to the original question in this thread:
I experienced breathing difficulties a few years ago similar to those
described.  In my case, it turned out that I was developing Type I
diabetes.  Although I never sought direct confirmation of this from my
doctor, I think that the breathing problem was associated with the
presence of ketones due to the diabetes.
I think that ketosis can occur in lesser degree if one is restricting
their food intake drastically.  I don't know if this relevant in this
case, but you might ask your daughter if she has been eating
properly.
--
Steve Kirchoefer                                             (202) 767-2862
Code 6851                                      kirchoefer@estd.nrl.navy.mil
Naval Research Laboratory                       Microwave Technology Branch
Washington, DC  20375-5000              Electronics Sci. and Tech. Division
From: jperkski@kentcomm.uucp (Jim Perkowski)
Subject: Re: jiggers
Distribution: world
X-NewsSoftware: GRn 1.16f (10.17.92) by Mike Schwartz & Michael B. Smith
Organization: Privately owned and operated UUCP site.
Lines: 26
In article <1ppae1$bt0@bigboote.WPI.EDU> susan@wpi.WPI.EDU (susan) writes:
> a friend of mine has a very severe cause of jiggers -
> for over a year now - they cause him a lot of pain.
>
> i recently read (i don't know where) about a possible
> cure for jiggers.  does anyone have any information on
> this?  i can't remember the name of the treatment, or
> where i read it.
>
I'll probably get flamed for this, but when I was a kid we would go to
my uncles cabin on Middle Bass Island on Lake Erie. We always came home