HDTenEightyP/NetNews huggingface dataset:
From: jstimson@jarthur.claremont.edu (John Stimson)
Newsgroups: sci.electronics,rec.audio,alt.folklore.computers
Subject: Re: Life after CDs
Date: 27 Jul 92 20:20:53 GMT
Distribution: na
Organization: Harvey Mudd College, Claremont, CA 91711

In article <1992Jul27.194532.15632@udel.edu> bower@peppermint.udel.edu (Tyson Bower) writes:
>As far as pressing the "grooves" on a CD closer together goes, I believe 
>they are already very nearly as close together as they can get.  They can
>be packed in slightly more (I think this is how some of those `long' 
>CD's are made to exceed the 74 min standard) but not much.  
>
>It has to do with limitations due to the wavelength of the red laser
>used to read the discs.  If the spiral track gets and tighter, the
>laser cannot accurate track a single row to pits/bumps.  Apparently,
>the solution to this restriction is to use a blue laser instead, which
>has a shorter wavelength and can therefore focus in on a smaller spot.
>Unfortunately, blue lasers are rather expensive and the technology
>does not yet exist to mass produce them at a realistic price.
>
>Does anyone know more about this?
>


That's all just fine, but once you start talking about a format that
you need brand new equipment to read, why bother?  Why not
just make the disc bigger then?

							John Stimson
							Harvey Mudd College
Newsgroups: sci.electronics
From: admerlev@sundae.triumf.ca ( Arnd Merlevede )
Subject: TOUCHtone "emulator"
Keywords: touchtone
Reply-To: admerlev@cipy.e-technik.uni-erlangen.de
Organization: University of British Columbia, Vancouver, B.C., Canada
Date: Tue, 28 Jul 1992 17:39:55 GMT

Hi, do you know if there is/was in one of the
apppropriate magazines a circuit to build a thing that creates
telephone touchtone dual-frequency tunes ?
(In order to control a answering machine in still mostly pulse-controlled
germany .)

Thanx for a pointer
Arnd

--
Any replies appreciated to : Arnd.Merlevede@cipy.e-technik.uni-erlangen.de
I hate to tell you, but you're only being simulated on the new cray !
(sdb: Would you like to save a backup of YOUR coredump ?)
Xref: sparky sci.electronics:13087 alt.folklore.urban:19382
From: dbushong@wang.com (Dave Bushong)
Newsgroups: sci.electronics,alt.folklore.urban
Subject: Re: SHOCKING STORIES
Date: 21 Jul 92 23:32:51 GMT
Followup-To: alt.folklore.urban
Organization: Wang Labs, Lowell MA, USA

thad@btr.BTR.COM (Thaddeus P. Floryan) writes:

>In article <7480@public.BTR.COM> grady@public.BTR.COM ( ) writes:
>>Just to take this thread on a morbid twist,
>>does anyone know what voltage and amperage
>>is used in state executions?

>Dunno, but I've "heard" that a person can be killed using a common 1-1/2V
>"D" cell battery, some wire, and two needles.

>No, you DON'T strangle the person with the wire, shove the battery down
>his throat, and bury him under a cross made from the needles!  :-)

>As it was related to me years ago, the point (no pun :-) of the needles
>was to penetrate the epidermis and present the battery's voltage to the
>highly-conductive "inner" layers of the person's body; if, say, one
>needle pierced each arm, the current would pass through the heart causing
>fibrillation leading to death.

>Probably a 12V car battery and jumper cables (with one clamped to, say, the
>big toe and the other to one's opposing arm) would effect the same result;
>'twould probably hurt, too!  :-)

I crossposted this to (and set followup to) alt.folklore.urban, and
I'm dying to see if this has come up before.  I know that I've heard
stories about low-voltage electrocutions; wonder if they're just
wishful thinking......

>Hmmm, what with all the concern about falsely-triggered car alarms awakening
>neighborhoods, what about having one's car charged up to some potential?

I've heard ULs about this one, too.

>Thief attempts to break in, ZZZ-Z-A-P *P*O*W*.  Only a millisecond disturbance
>to the neighbors, followed by the thief's quiet wimperings!   :-)

Wish it were true, too!

Dave
-- 
==========================================================================
Dave Bushong, KZ1O@K1UGM.MA         +    No .sig, no tattoo, 
Wang Laboratories, Inc.             +        no bald spot, no nothin!!
Internet: dbushong@wang.com         +-------------------------------------
Project leader, OCR Products        + (reserved for future expansion)
Organization: Penn State University
Date: Fri, 31 Jul 1992 14:54:50 EDT
From: <GNR100@psuvm.psu.edu>
Newsgroups: sci.electronics
Subject: 8 bit to 3 digit BCD

      I need an encoder to go from 8 bit binary code to its equivelant
3 digit binary coded decimal.  Is there any thing like this commercially
available?  I could design and build it myself, but I would like to save the
time, effort, and cost if at all possible.

                  Thanks,
                    Gordon Rogers
                       gnr100@psuvm.psu.edu
From: rg@futserv.austin.ibm.com (R.G. Keen)
Newsgroups: sci.electronics
Subject: Re: Coil Gun Construction
Date: 22 Jul 92 15:28:21 GMT
Reply-To: ...@cs.utexas.edu:ibmaus!auschs!tmn1.austin.ibm.com!tung
Organization: IBM Coporation - Advanced Workstations Division.

Do a literature search on linear induction motors, perhaps 
also on author E. H. Laithwaite (not terribly sure of the 
spelling).
Newsgroups: sci.electronics
From: schmidt@auvax1.adelphi.edu
Subject: Re: SHOCKING EXPERIENCES
Organization: Adelphi University, Garden City NY
Date: Mon, 27 Jul 1992 05:51:28 GMT

Some years ago, about 20, I think, someone in the experimental psych lab here,
having tired at shocking rats ran an experiment with humans.  

They wanted to determine people's sensitivity to electric shock.  The equipment
used was crude and simple, a Variac with a voltmeter hooked up to the output,
and two test leads.  The "victim" (not their term :-) ) held the two leads, one
in each hand, as the experimenter slowly turned up the Variac.  You were
supposed to tell them 1) when you first felt the shock, and 2) when it became
"uncomfortable".  I agreed to be a "subject" (their term)  I recall that I
could just feel 50v, and that "uncomfortable" turned out to be just about 110v!
but then, I've been hit a few times before.  There was a wide range I'm told. 
One "subject" felt 12v.  No ones heart stopped, so I guess they were lucky.

I'm sure a foolish experiment like this would never pass all the reviews that
human experiments are supposed to get these days.

My worst shock came from the secondary "plate" winding of an old radio plate
transformer also, when I was in high school.  I'll never forget, I had a big
problem letting go, it seemed forever, but I'm still here, I guess.  I felt it
for weeks afterwards in my chest and arm muscles.  Another time I hit the back
end of a fuseholder in a piece of gear when I didn't expect it and yanked my
arm back so hard I dislocated my shoulder.  That was just 110, but when it gets
you by surprise!!!  Actually I am almost as concerned with getting burned by
shorting out 110 as I am with getting zapped.  I could tell you about some
pretty serious accidents I've seen the after effects of where electricians
accidentally shorted out high current feeders.  Many have been badly hurt by
the flash, not by the shock.  

Anyone who survives contact with high voltage power "primary" wiring is very
lucky.  If you've ever seen 13KV primary (actually 7600v to ground) that's
laying in the street, you know what I mean.  We once had a contractor's
electrician here who pulled the 13KV primary fuses on a transformer here open
with his bare hands, while standing on the concrete pad, next to it.  He was
lucky, the holders were dry and clean, but he s>*# in his pants when he opened
the third fuse and the arc from the exciting current carried about two inches
before breaking.  This is a true story!

-- 
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Newsgroups: sci.electronics
From: iisakkil@vipunen.hut.fi (Mika R Iisakkila)
Subject: Re: Green Layer on Circuit Boards?
Organization: Helsinki University of Technology
Date: 23 Jul 92 20:29:05

adw@cci632.cci.com (Allen Williams (co-op)) writes:

> However, one step that I think would be a good addition is the green
>layer of plastic insulation that commercial circuit boards have.

It's not really plastic. I'm not 100% certain of the procedure, but it
is some liquid chemical. It is applied in much the same way as the
protoresist used in etching. You provide the PCB manufacturer with a
film of the non-coated regions of the PCB, and they do the rest :-)
I believe that they photographically create a resist layer on the PCB
to screen the soldering pads, and then apply the solder mask chemical.
After the mask has been hardened, the resist is removed and the pads
metallized to prevent them from oxidation.

> Although it's not absolutely necessary to have insulated traces, I feel 
>that it would be better in the long run to reduce the chances of short
>circuits as boards tend to accumulate dust and crud during long term use.

This is not usually an issue if the board is not used in moist
conditions. The main advantage of the solder mask layer is that it
prevents solder bridges and short-circuits during wave soldering in
mass production. It helps hand soldering too, but you can usually
manage without the mask.

--
Segmented Memory Helps Structure Software
Newsgroups: sci.electronics
From: ssave@ole.cdac.com (Shailendra Save)
Subject: Re: 0.100" spacing
Organization: Cascade Design Automation, Bellevue, WA
Date: Fri, 24 Jul 1992 19:38:47 GMT

In article <1992Jul24.135835.21402@cci632.cci.com> adw@cci632.cci.com (Allen Williams (co-op)) writes:
>
> My fantasty drill press accessory is a X-Y sled that fits on the bench of the
>drill press. This sled would have clips that my circuit board attaches to. When
>I twist some screws, the sled locks, and when I push it in an X or Y direction,
>it clicks and locks at every 0.100". Does such a thing exist, or will someone
>take this idea, make a fortune selling these sleds, and give me a free sled
>in exchange?
>
>
> Any tips or pointers would be deeply appreciated.
>
>                                                              Derrick


  This has been done before. :-)   And it is not necessary to turn the
x-y yourself. All you need are the (x,y) co-ordinates of the PCB on a PC,
which turns stepper motors, to the right location; then another stepper
lowers and lifts the drill.  That way, you can prototype quite fast a 
number of PCBs consistently.

  I don't have any names of manufacturers. Sorry.


  -Shailendra
  ssave@ole.cdac.com
Newsgroups: sci.electronics
From: edg@ecs.comm.mot.com (Ed Gonzalez)
Subject: CD4098 Multivibrators anyone?
Organization: trunking_terms
Date: Tue, 21 Jul 1992 21:47:28 GMT


Thanks a lot for all your help on the 555 issue.

Here is another question:

Does anyone know of a book that talks about the CD4098 multivibrator?
THis is an RCA chip, and I believe its counterpart is Motorola's 
MC14528 which lists the  MC14538  as preferred "for new development".
ANyhow, I got the cd4098

This is a dual multivibrator. What I really need to know is
the formulas to figure out the timing and how long it will stay "down"
and then how long it will be "UP". Also what type of input is it 
waiting on, etc.    I read somewhere that the resistor that goes on the
RC circuit on this chip should be >= 5K ohm.  They did not explain
why. The publication did NOT say that timing would be erratic if I
placed a lower value resistor.



Any info send direct to me:

edg@comm.mot.com  (Otherwise known as the hardware beginner).

Thanks.


Newsgroups: sci.electronics
From: neufeld@helios.physics.utoronto.ca (Christopher Neufeld)
Subject: Re: Fry the Monkey
Organization: University of Toronto Physics/Astronomy/CITA
Date: Wed, 29 Jul 1992 15:08:16 GMT

In article <1992Jul28.154422.41939@kuhub.cc.ukans.edu> wellison@kuhub.cc.ukans.edu writes:
>
>It seems that a FE in Atlanta, Ga. was working on a PDP-11/34 that was
>used in controlled experments on the brain stimulus of live monkeys. The
>11/34 was hooked up to a DAC setup that was hooked into a interface that
>was wired to a monkey's skull. [...] So he fires up DEC-X and the
>diagnostics run the DAC's from minumim to maximum voltage, which fried the
>monkey's brain.
>
   Well, coincidences abound. Here's something from today's feed on
alt.folklore.computers:


--- BEGIN INCLUDED ARTICLE ---

Article: 27039 of alt.folklore.computers
From: lupe@ukw.uucp (Lupe Christoph)
Newsgroups: alt.folklore.computers
Subject: Re: Computers killing people? (WAS Re: 9 track data storage???)
Date: 27 Jul 92 22:02:16 GMT
Organization: cic

[ ... ]

Not exactly at the point, but the jargon file entry {scratch monkey}
applied here:

:scratch monkey: n. As in "Before testing or reconfiguring, always
   mount a {scratch monkey}", a proverb used to advise caution
   when dealing with irreplaceable data or devices.  Used to refer to
   any scratch volume hooked to a computer during any risky operation
   as a replacement for some precious resource or data that might
   otherwise get trashed.

   This term preserves the memory of Mabel, the Swimming Wonder
   Monkey, star of a biological research program at the University of
   Toronto ca. 1986.  Mabel was not (so the legend goes) your ordinary
   monkey; the university had spent years teaching her how to swim,
   breathing through a regulator, in order to study the effects of
   different gas mixtures on her physiology.  Mabel suffered an
   untimely demise one day when DEC {PM}ed the PDP-11 controlling
   her regulator (see also {provocative maintenance}).

   It is recorded that, after calming down an understandably irate
   customer sufficiently to ascertain the facts of the matter, a DEC
   troubleshooter called up the {field circus} manager responsible
   and asked him sweetly, "Can you swim?"

   Not all the consequences to humans were so amusing; the sysop of
   the machine in question was nearly thrown in jail at the behest of
   certain clueless droids at the local `humane' society.  The moral
   is clear: When in doubt, always mount a scratch monkey.
-- 
| ...!unido!ukw!lupe  (German EUNet, "bang")     |  Disclaimer:            |
| lupe@ukw.UUCP       (German EUNet, domain)     |  As I am self-employed, |
| suninfo!alanya!lupe (Sun Germany)              |  this *is* the opinion  |
| Res non sunt complicanda praeter necessitatem. |  of my employer.        |


--- END INCLUDED ARTICLE ---


-- 
 Christopher Neufeld....Just a graduate student  | Talk sense to a fool
 neufeld@helios.physics.utoronto.ca    Ad astra  | and he calls you
 cneufeld@terranet.cts.com                       | foolish.
 "Don't edit reality for the sake of simplicity" |       - Euripides
From: dino@inqmind.bison.mb.ca (Tony stewart)
Newsgroups: sci.electronics
Subject: Re: White noise generator.....
Date: Tue, 28 Jul 92 00:04:10 CDT
Organization: The Inquiring Mind  1 204 488-1607

nall@sun8.scri.fsu.edu (John Nall) writes:

> Since I did fairly well at getting my previous question answered
> on this newsgroup, thought I'd push my luck and ask another :-)
> 
> I'm one of those people who has to have some "white noise" in the
> background to sleep.  Something like a fan, or rain on the roof,
> or wind in the trees, something like that.  I have a device which
> I use at home, which is a combination radio/alarm-clock/noise-generator
> with a couple of good sized speakers and runs on 110v AC.  It works
> fine - generates sound (switch control to either a constant sound or
> else the sound of surf breaking on a beach) which lulls me to sleep
> and hides such things as dogs barking in distance, etc.
> 
> So far so good - this works fine at home.  But it is large and bulky,
> and trying to carry it on a camping trip or on quick out-of-town
> trips is a drag.  Some motels have room air conditions which serve
> the purpose, but not always.
> 
> Anyway...finally....it seems to me that if there is a sound-generator
> chip available, that a little portable unit could be made, which would
> run on ni-cad batteries (so that it could be recharged), with a small
> speaker such as is found in a cheap transistor radio.  If put close to
> the ear when sleeping, it should do the trick.
> 
> Does anyone know of such a device?  If not, is there a such a noise-
> generator chip available?  (I don't have access to any sort of technical
> material on what chips are available these days).
> 
> BTW, if there is NOT such a device available, someone could probably
> make money by making one.  There are zillions of people like me, who
> have to have noise to sleep :-)
> 
> Thanks for any info.
> 
> John
> 
> 
> --
> John W. Nall              | Supercomputer Computations Research Institute
> nall@mailer.scri.fsu.edu  | Florida State University, Tallahassee, FL 32306
>     "You cannot be a beacon, if yo' light don't shine!"  
>                                             - heard on the car radio...

I bought a white noise chip 15 yrs ago from either National or Fairchild.
It probably is obsolete by now. It looks good on a spectrum analyzer but  
the repetitive pseudo-random noise sequence sounded more like an engine 
with a 3 second repeating noise cycle (very noisy engine). I made a 3 
dB/oct pink noise filter and was intending to equalize my room acoustics 
with it ....an unfinished project...

dino@inqmind.bison.mb.ca
The Inquiring Mind BBS, Winnipeg, Manitoba  204 488-1607
Newsgroups: sci.electronics
From: medin@catbyte.b30.ingr.com (Dave Medin)
Subject: Laser printer parts
Reply-To: medin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Date: Thu, 23 Jul 1992 16:06:03 GMT

A short for-sale article...

I've got some operational parts (scanning motor, HV supplies, laser, optics)
from an old Ricoh printer I just parted out. If you're interested, please
E-mail me.

I've also got some HP 432 RF power meters (3), if you're interested.

-- 
 --------------------------------------------------------------------
       Dave Medin			Phone:	(205) 730-3169 (w)
    Intergraph Corp.				(205) 837-1174 (h)
       M/S GD3004
  Huntsville, AL 35894 		Internet: medin@catbyte.b30.ingr.com
				UUCP:  ...uunet!ingr!b30!catbyte!medin
Newsgroups: sci.electronics
From: medin@catbyte.NoSubdomain.NoDomain (Dave Medin)
Subject: Re: Radar Detectors, and Radar Detector Detectors
Keywords: Radar
Reply-To: medin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Date: Mon, 27 Jul 1992 22:22:58 GMT

In article <1992Jul23.204831.28487@news.columbia.edu>, gmw1@cunixa.cc.columbia.edu (Gabe M Wiener) writes:
|> In article <92Jul23.162259edt.176@orasis.vis.toronto.edu> oliverb@vis.toronto.edu (Oliver Bengtsson) writes:
|> >   Could someone out there please tell me how a radar detector detector
|> >works? I thought that a radar detector was a passive device, nothing more
|> >than a receiver tuned into detect a certain radio frequency used in radar
|> >guns. If this is the case, how can they be detected?  
|> 
|> All receivers work by resonance, and this resonance can be detected with
|> the appropriate equipment.

<BBC stuff deleted>

Well, not quite. "Detector detectors" are designed to look for leakage power
at common IFs (intermediate frequecies) of the device they're trying
to detect. This works if the receiver they're trying to detect is
of "superheterodyne" type, which most TV sets and radar detectors are.
It has nothing to do with detecting resonance, which can only be done
efficiently at really close range (like with a grid dip meter in the
circuit) and generally right on the antenna aperature.

The set or radar detector has an oscillator(s) inside it which is used
to mix down the incoming carrier frequency of the TV/radar to a lower
frequency more easily filtered and processed. The IF oscillator(s)
will have some leakage to the outside world where it can be
detected by a tuned receiver or spectrum analyzer. Try this
sometime... common TV IF's are 75 and 10.4 MHz. Listen in on
your set's IF leakage with a general coverage receiver. The leakage power
is in the 10's of milliwatts, usually. Try 220 MHz for your radar
detector...

Incidentally, IF leakage is one of the prime reasons TV sets have
to receive FCC type-acceptance before sale to the general public...

-- 
 --------------------------------------------------------------------
       Dave Medin			Phone:	(205) 730-3169 (w)
    Intergraph Corp.				(205) 837-1174 (h)
       M/S GD3004
  Huntsville, AL 35894 		Internet: medin@catbyte.b30.ingr.com
				UUCP:  ...uunet!ingr!b30!catbyte!medin

   ******* Everywhere You Look (at least around my office) *******

 * The opinions expressed here are mine (or those of my machine)
Newsgroups: sci.electronics
From: rmintz@ecst.csuchico.edu (Rich Mintz)
Subject: Ring Signal/Software Problem
Organization: California State University, Chico
Date: Sat, 25 Jul 1992 05:26:16 GMT

I have an application I've programmed that monitors the phone line.
I've had a constant problem keeping track of how many time the phone
has rung, because of all the specific timing problems associated with
checking for the duration of a ring, how long after ringing stops to
reset the count, considerations for passing through the ring-check
procedure in mid-ring, while constantly monitoring if the phone has
been answered (I'm using a voice mail card that can detect a pickup on
the connected telephone) and doing miscellaneous other processing.
 
Through trial and error, I can sometimes get it to work right, but
when I change to a different type/speed of computer, or change some
aspect of the program that will affect the timing checks, it messes
everything up. The RI serial line also jumps between 1 and 0 very
quickly when a ring is detected, which complicates the routine to
reliably determine the presence or absence of a ring. This indicator
also seems to get falsely triggered sometimes when a pickup or hangup
is made. I had considered constantly polling the Hayes S1 register on
the modem with serial i/o (it keeps track of how many rings have
occurred), but there were problems with polling commands to the modem
getting messed up when the modem would send a ring result code at the
same time as commands were being sent to it, which made that method
unreliable. On top of that, I found that doing serial i/o in Turbo C
isn't exactly fun (ie: pain in the ass).
 
I have the phone line going into my modem, and then to my voice mail
card, which then software-selectably passes the line to a connected
telephone. I disengage the phone from the line via software at times
when I don't want my phone to ring. If I put a rectifier bridge and a
big capacitor on the phone line going into the modem/voicemail card,
will it (A) still ring my phone when I select to pass the line through
to the connected (electronic ringer) telephone, and (B) register as
ring detect to the modem and produce a continuous "1" signal on the
serial RI line (as opposed to the normal 1..0..1..0 ring signal), and
(C) screen out false '1' "blips" in the signal when I pick up or
hangup my phone? In other words, will just the positive portion of
the AC ring smoothed out with the capacitor so that it appears to the
various ring-detect circuitry as a very elevated DC voltage be
recognized as a ring? If not, is there an alternate configuration
someone can suggest that would do this job?
 
Note: my modem is internal and I'm using an AT 386 SX @ 16 Mhz.
 
Thanks a lot . . .
 
      Rich -> rmintz@cscihp.ecst.csuchico.edu

Xref: sparky sci.electronics:13247 comp.sys.ibm.pc.hardware:20229