HDTenEightyP/NetNews huggingface dataset:
From: orscholz@immd4.informatik.uni-erlangen.de (Oliver Scholz (Turo - Backstage))
Subject: Re: police laser radar
Organization: CSD., University of Erlangen, Germany
Date: Wed, 18 Nov 1992 16:29:12 GMT

Ken Wilkens <wilkens%nmr@venus.ycc.yale.edu> writes:

>Well I was thinking about putting laser diodes on the front of my car
>also soon as I found what wavelength the operate at. I don't think it
>would take much power to foul the lidar as it uses reflected power which
>should be alot less than you would be broadcasting. As for the legal
Exactly. That's why you don't need lasers. Remember, if you use a laser, you
have to aim directly at the speed gun to jam it effectively. Why not use
IR-LEDs? Their light is much more diffuse, and as you stated, the LEDs
should be much 'brighter' than the reflection from your car.

-O.
-- 
----------------------------------------------------------------------------
Oliver Scholz                                                         DG4NEM
Graduate Student of Computer Sciences at the University of Erlangen, Germany
"You're killing me, Peg!"  "Oh, shut up, Al, like I care..." 
From: pauls@trsvax.tandy.com
Date: 20 Nov 92 11:46 CST
Newsgroups: sci.electronics
Subject: Re: DTMF Decoder (I know -- "AGAIN?")
Message-ID: <288200030@trsvax>
Nf-ID: #R:<92323:19415834:trsvax:288200030:000:801
Nf-From: trsvax.tandy.com!pauls    Nov 20 11:46:00 1992


I will assume that you can solder, wire-wrap or whatever....

1) Decoders come in 2 flavors: "toll-quality" and "regular". The
toll-quality decoders (ie more $$$) have the following traits:

- better "talk-off". This is rejecting talking for DTMF tones
- better dial-tone rejection
- better "twist" reception. Twist is a stupid name for the amplitude
difference between the dual-tones. Usually this is around 2-3 dB.

THe leader of "toll-quality" chips is Teltone, with Mitel a close second.

2) The second-teir folks are good enough for home projects. The leader
there is Silicon Systems, with other chips like Sierra Semi.

If you want a schematic, then send me a SASE. I will provide circuits for
all known DTMF chips!
\
Paul Schreiber
200 Taylor St. #6244
Fort Worth, TX 76102

No SASE, no dice!
From: slgnj@cc.usu.edu
Newsgroups: sci.electronics
Subject: Re: Big Brother Radio Shack
Date: 20 Nov 92 21:12:27 MDT
Organization: Utah State University

In article <1e9fg4INNaul@matt.ksu.ksu.edu>, danodom@matt.ksu.ksu.edu (Dan Odom) writes:
> ac94691@dunix.drake.edu (The Dark Kitty) writes:
> 
>>Oh yeah, did this click real well in my mind.  I don't know how many
>>times I've gone into the local Radio Rip Off Store and asked for a
>>certain size of capacitor/resistor that hasn't been restocked only to
>>be told "capacitors?  I'm not sure I know what those are.  I don't think
>>we carry those."  Aiiiiiigggghhhh!!!  I also don't know how many times
>>I've been browsing and overheard a salesman tell another customer that
>>RS doesn't carry an item that I happen to be looking right at!
> 
> Yes, or when they tell you "If you want to get a transformer for your kid,
> try Toys-R-Us.  We don't do that stuff.".  Or "What's an IC again?".
> Or "RJ14?  Is that the new computer game?".  Or (etc. etc. ad nauseam (sp?))
> I go mail order whenever possible.
> -- 

If you MUST shop at Radio Shack, the best thing do do is avoid the sales people
(if that's possible, considering the way they come charging out at you) and
try to find what you're looking for on your own. Its faster, and much less 
agrivating. 

Usually, the best way to get the parts you want is by mail order, its generally
a lot cheaper (everything isn't indivually wraped), and you have a much better 
chance of finding what you're looking for.

                         Drew
From: p00140@psilink.com (Gary A. Woodward)
Newsgroups: sci.electronics
Subject: fm rf transmit allowed?
Date: 19 Nov 92 00:58:50 GMT
Organization: Performance Systems Int'l
X-Mailer: PSILink (3.2)

Hello. I have a question.  I want to build and sell some of the wireless 
miniature fm transmitter mics you see advertised in mags.  I want to 
hook up an enless loop tape player to it.  Will this be legal?  I will 
be transmitting only on dead air.

thanks in advance

GW
Newsgroups: sci.electronics
From: schuch@phx.mcd.mot.com (John Schuch)
Subject: Re: DTMF Decoder (I know -- "AGAIN?")
Organization: Motorola Computer Group, Tempe, Az.
Date: Fri, 20 Nov 1992 12:38:54 GMT

In article <92323.19415834II5MT@CMUVM.CSV.CMICH.EDU> 34II5MT@CMUVM.CSV.CMICH.EDU (John Goggan) writes:
>This comes up now and then and I'm always interested, but no one ever
>seems to come up with a definate answer.  I'm looking for a schematic
>for a touch-tone decoder circuit.  Something that simply takes audio
>input and lights an appropriate LED for 0-9,#,*,A-D when it "hears"
>
>I'd almost given up hope and forgotten about the project for a while when
>I recieved the new All Electronics catalog (#492)...  One of the items
>offered is some "revolutionary toner-transfer paper" or something.
>Anyways, the picture included next to that ad is one side of a pc board
>etching -- and the title is etched on it -- "TONE DECODER."  If you

If you have a FAX machine, I'll send you a schematic for a DTMF to
LED display which only uses 9 parts.

John

(If I can figure out how to get a postscript file out of Island Draw,
 I'd be willing to post it to the net. )


-- 
| ONE LINE NOVEL: She backed away from the corpse slowly, not so much out  |
| of fear, but simply unsure of what the crowd expected her to do with it. |
+--------------------------------------------------------------------------+
| John R. Schuch  -  Motorola Computer Group  -  Manufacturing Engineering |
From: sehari@iastate.edu (Babak Sehari)
Newsgroups: sci.electronics
Subject: Re: Logic Addition
Date: 16 Nov 92 01:09:49 GMT
Article-I.D.: class1.sehari.721876189
Organization: Iowa State University of Science and Technology, Ames, Iowa.
Originator: sehari@class1.iastate.edu

In <#-t1l#n@rpi.edu> wilusd@cary115.its.rpi.edu (David John Wilusz) writes:


>	Perhaps sci.electronics is not the place for this, but where is?  Could someone give me the configuration of gates that allows binary numbers to be correctly added?
>	Thanks for any help...

>	Dave

It is called an adder, It has one exclusive OR and a AND gates.


Here it is:

               a---+----
                         \___|------
                          ---| XOR |-----Lo 
                         /   -------
               b--------
               a---+----
                         \___|------
                          ---| AND |-----Co
                         /   -------
               b--------

                  With highest regards,
                       Babak   Sehari.
-- 
Newsgroups: sci.electronics
From: kbass@gmuvax2.gmu.edu (Ken Bass)
Subject: Re: Cable TV Rules
Organization: George Mason University, Fairfax, Va.
Date: Thu, 19 Nov 1992 16:03:25 GMT

In article <1992Nov5.122636.5499@hemlock.cray.com> andyw@aspen32.cray.com (Andy Warner) writes:
>
>In article <720883631snx@nlbbs.UUCP>, paula@nlbbs.UUCP (Paula Stockholm) writes:
>> 
>> [...]
>>         I'm the last one who would be considered and advocate for the
>>         Cable Companies but . . . suppose you wanted to hook-up another
>>         water heater - you would expect to pay for the extra juice.
>> 
>>           The cable signal is not as easily "meter-able" but you would
>>           be using more cable signal.
>
>Good analogy. The power company at least has the honesty to put
>a meter on your feed, and charge you accordingly. They don't
>snoop around checking what you've got connected (at least past
>your meter). Every other utility has expended a non-trivial
>amount of effort to bill you according to usage, it seems that the
>cable & sat carriers would rather expend effort legislating than
>developing a metering method (a gross generalisation, which I will
>probably be mercilessly flamed for)..
>
>>       I DO agree that often the extra charge seems excessive.
>
>It seems to me any of the charges seem excessive.
>-- 
>andyw.	N0REN/G1XRL
>
>andyw@aspen.cray.com	Andy Warner, Cray Research, Inc.	(612) 683-5835

Bad analogy. You are talking about additional power versus the use of a
signal already there. It is my belief the duplicate cable signal used
changes their power requirements little. I'd be interested if somone
knowledgable could confirm or deny this.

Secondly, the power use to amplify the degraded signal is my own, from
the electric company. The electric company had to crank up consumption
of fuels, etc. The cable company doesnt do squat. It is just a way to
rip people off because they are a monopoly. It is a serious abuse of
power and is why they need regulation.
   ---Ken

-- 
Ken Bass (kbass@gmuvax2.gmu.edu)              |   Telecommunications  
George Mason University                       |   Techniques Corp, 
Student, Department of Electrical Engineering |   Software Engineer
From: dino@inqmind.bison.mb.ca (Tony stewart)
Newsgroups: sci.electronics
Subject: Re: Cable TV Tech Question
Date: Sun, 15 Nov 92 01:36:43 CST
Organization: The Inquiring Mind BBS  1 204 488-1607

duncan@ravel.ati.com (Jim Duncan) writes:

> In article <lfti4mINNlfu@jethro.Corp.Sun.COM> acm@Sun.COM (Andrew MacRae) wri
> >Everything is fine *except* that I don't get any thing on channels above 13.
> >checked the amp and it is supposed to amplify VHF, UHF, and FM. 
> 
> CATV channels and off-air channels operate on different carrier
> frequencies above channel 13.  So you need to buy an amp made
> specifically for cable TV.
> 
> Typically, a CATV amp functions continuously from 50 -550 mHz. while the
> off-air unit you apparently bought works over discontinuous bands: 50 -
> 108, 170 - 213, and 470 - 800 mHz.  If your cable company provides lots
> of channels, you'll find that your off-air amp stops working at channel
> 13 and then starts up again around cable channel 60.   
> 
> -- 
> KUFX |      w  ["]                            | WA6MBV     
> 94.5 |...   |___|_____..duncan@ravel.ati.com  | Jim Duncan  
> FM   |          H                             | ----------   
> ********  \_____I_____/  37 3 10N/121 59 10W  ************** 

You should at least get the mid band channels from 14 to 23 which lie 
between the freq for 6 & 7.
Make sure your TV is set to CATV. Otherwise you'll only see 2-13.

dino@inqmind.bison.mb.ca
The Inquiring Mind BBS, Winnipeg, Manitoba  204 488-1607
From: matthew@basser.cs.su.oz.au (Matthew Geier)
Subject: Were can I get this wierd RAM
Reply-To: matthew@cs.su.oz.au (Matthew Geier)
Organization: Basser Dept of Computer Science, University of Sydney, Australia
Date: Tue, 17 Nov 1992 22:03:59 GMT

 I recently obtained a 2nd hand Tektronix workstation. While the system works
quite well it needs more RAM. The motherboard is provided with LOTS of SIMM
sockets. The catch is that these SIMM's are 80 pin 36 bit SIMMs, when the
standard appears to be 72 pins (for 36 bit SIMMs).

 The local Tek people dont know off hand the price of more RAM , but indicated
that I wouldnt like the price , and that it would cost several times what I
payed for the rest of the machine.

 There doesnt appear to be any exotic parts on the Tek SIMM modules, just 
standard RAM chips and a 74AS04. The modules have Teks name in the artwork,
so they were probably custom made.

 If any one has come across 80 pin ( 40+40 ) SIMMs , I definatly would like
to hear from you...

Newsgroups: sci.electronics
From: rda735z@nella16.cc.monash.edu.au (Simon Cocking)
Subject: Motorola BBS mirror ftp site?
Organization: Monash University, Melb., Australia.
Date: Thu, 19 Nov 1992 07:32:56 GMT

Is there an FTP site around the place which mirrors the Motorola BBS?  My
reason for asking is that placing a call to the BBS from Melbourne,
Australia is probably going to stretch my limited budget a little :-)

Thanks,
Simon.
-- 
+---------------  Simon Cocking, sgc@yoyo.cc.monash.edu.au  -------- /// -+
|               Robotics & Digital Technology / GAUnix Group        ///   |
|                             Monash University                 \\\///    |
+-------------------------  Melbourne, Australia.  ------------- \XX/ ----+
Newsgroups: sci.electronics
From: medin@catbyte.b30.ingr.com (Dave Medin)
Subject: Re: Using big caps as computer power supply filters (?)
Reply-To: medin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Date: Tue, 17 Nov 1992 20:28:00 GMT

In article <1992Nov17.165023.29174@julian.uwo.ca>, wlsmith@valve.heart.rri.uwo.ca (Wayne Smith) writes:
|> I've got some big electrolytic caps (20000 to 60000 uf, 16 to 40 volts),
|> and I was thinking of putting them across the 5V and 12V power supplies
|> in my pc.  I would think that cap's that big would provide maybe 1
|> second of backup power.  Should I use some inductors or smaller
|> caps with these big guys (to make them safer), or are they pretty reliable
|> on their own (I wouldn't want them exploding inside my pc).  :)

Be careful on this one, as the caps applied directly across the
rails will possibly cause the power supply to current limit
and turn off, blow a fuse, or smoke itself. Also, you may see
oscillation because of the large capacitive load.

You might try attaching the caps to the bus through a 5 ohm (5 volt)
and 100 ohm (12 volt rail) resistor, each in parallel with a schottky
diode (cathode or banded end oriented towards the power bus). The
schottky diode is a must, for its low forward voltage drop.
Unfortunately, high current (20 amps for the 5 volt line)
schottkys are not easy commodities to find for a hobbyist,
although the dual diodes found in PC power supplies are often
schottkys and could be used.

Note that the above is risky anyway, as some power supplies use linear
post-regulation on the 12 volt line. Supplying 12 volts from
the cap may back-bias linear regulators in the supply possibly
resulting in fried or compromised components. I've never seen
a PC supply whose 5 volt section could be damaged this way, though.

Another problem... Most PC power supplies have a line monitor
which detects AC and DC faults (loss of line power being one).
This signal, available through the power supply connector,
puts the MB into reset. This line would have to be defeated,
with possible power-on consequences (the MB coming up
before power was stable).

In short, although it would make an interesting experiment, I wouldn't
be doing it in my machine.

-- 
--------------------------------------------------------------------
       Dave Medin			Phone:	(205) 730-3169 (w)
    SSD--Networking				(205) 837-1174 (h)
    Intergraph Corp.
       M/S GD3004 		Internet: medin@catbyte.b30.ingr.com
  Huntsville, AL 35894		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,rec.photo
From: mwandel@bnr.ca (Markus Wandel)
Subject: Lamp intensity vs. lifetime (was Re: 486 CPU KOOLERS FOR SALE)
Organization: bnr
Date: Mon, 16 Nov 1992 16:41:01 GMT

In article <Bx93z4.n2B@cs.dal.ca> legrady@ug.cs.dal.ca (Tom Legrady) writes:
>
>I don't know about the exact relationship of heat and lifetime for
>electronics comnponents, but there is an inverse exponential effect on
>the life of high-intensity lamps, such as the ones used for stage
>lighting. I have to fudge the exact numbers, since I've been out of
>theatre for a number of years, but dropping a lamp to 90% full
>intensity generally doubles the expected life of a lamp. Dropping to
>80% results in an unlimited expected life. Since our reaction to light
>is non-linear, dropping to 90% has little effect on preceived
>brightness. Since the lamps used cost $30 - $50  or more apiece and
>have an expected life ranging from 300 - 2000 hours, doubling the life
>is a desirable things to do. Of course, if you drop it, it still dies. 

What about photographic floodlights?  These things have expected lifetimes
of just 2-8 hours.  I thought if I ever use the lamps and bulbs that I have
I would build a control box that allows the lamps to be dimmed until the
moment they are needed (for a still photo), then increased to full intensity,
then dimmed again.  That would save on heat, lamp lifetime, power
consumption, etc.  Several ways to dim a lamp come to mind:

  1. Two identical ones in series
  2. Diode in series (halfwave rectification)
  3. Electronic dimmer.

But there are a couple of things I am not sure about.  Lamp dimmers cause
light bulbs to buzz, surely not a good thing for a fragile, overheated
filament you are trying to extend the life of.  The diode approach also
messes with the AC waveform.  Two in series sounds pretty good, but when
I switch over, the lamps will be briefly off, then fired up to full
intensity.  Would this switching transient and associated rapid heating
or cooling of the filament be just as bad for the bulb as leaving it on
high intensity in the first place?  I'm guessing this because most bulbs
I've seen burn out did so when turned on.

Anyone have any experience in this?

Markus Wandel
markus@pinetree.org <-- NOT the source of this posting
Newsgroups: sci.electronics
From: ray@ole.cdac.com (Ray Berry)
Subject: Re: 'DreamLight' wanted!
Organization: Cascade Design Automation
Date: Wed, 18 Nov 1992 18:02:45 GMT

     The device you refer to is available from the following company:

         Tools for Exploration
         4460 Redwood Highway, Suite 2
         San Rafael, CA  94903
         voice tele 415-499-9050
         fax tele 415-499-9047

    The current price is US $999.95.  If you can talk TfE into sending you
their catalog, you might enjoy browsing 80 pages of brain tech stuff,
biomagnets, brainpower drugs, biocircuits, sound/light machines, etc. 

    Also, look for two books on the subject of lucid dreaming by a man 
named Stephen LaBerge.  Both are available in paperback.  The first
is titled "Lucid Dreaming", the 2nd "Exploring the World of Lucid
Dreaming".  They are US $5.95 each from TfE- or perhaps you can get
them in your part of the world.
-- 
Ray Berry kb7ht ray@ole.cdac.com 73407.3152@compuserve.com /*inquire within*/
Newsgroups: sci.electronics
From: jhwhit01@ulkyvx.louisville.edu
Subject: Re: Sega Genesis Guts And Operation...
Date: Wed, 18 Nov 1992 03:54:11 GMT
Organization: University of Louisville

In article <1992Nov18.005837.11091@cis.ohio-state.edu>, rubin@skiing.cis.ohio-state.edu (Daniel Rubin) writes:
> Anyone know anything about the Sega Genesis game console?  I opened one up
> and there is some interesting stuff inside.  A 68000 microprocessor, a 
> Z80 microprocessor, a couple large Sega chips ( each surface mount with about
> 25 pins all all four sides ), A yamaha chip ( I imagine for sound ), several
> Sony chips ( video? ) and a 53 MHz clock.  I really didn't see any memory
> chips, but maybe I just didn't look hard enough...
> 
> Anyone know about the architecture of this machine.  Why two microprocessors?
> 
> 								- Dan
  
The earlier Sega machine (forgot its name) used the Z80.  The 68000 was put in
the Genesis so that it could be called 16-bit and better performance could be
attained.  The Z80 was left in there so that games for the earlier machine
would be compatible.  The Yamaha chip is the video chip I think.  If you give
me the number off the top, I can be sure.  The computer I am using has a
Yamaha video chip in it, and I know how it works.  
 
Jeff White     jhwhit01@ulkyvx.louisville.edu
Newsgroups: sci.electronics,rec.video
From: fontana@apache.cis.ohio-state.edu (Mark Fontana)
Subject: Circuit to vertically crop NTSC video (letterbox)
Followup-To: sci.electronics
Organization: The Ohio State University Dept. of Computer and Info. Science
Distribution: usa
Date: Tue, 17 Nov 1992 16:50:51 GMT



Hi,

I'm interested in constructing a circuit to place in line while
dubbing video between two standard NTSC VHS VCR's that would allow
variable cropping of the image for a "letterboxed" effect.  There would
be two potentiometers (top and bottom) that would control how far the
black borders extend into the image, with a range of "no black at all"
to "black extends nearly to center of picture".  This would make it easy
to experiment with shooting video in different aspect ratios, ie. 1:1.85,
1:2.33.  (The original video would be shot full frame just like film;
I would impose the hard matte when editing or for final playback.)

I'm sure this effect can be achieved with computer overlay boards, Amigas,
and consumer-level editing/effects consoles, but I don't have any of these,
and a limited income.  Is this a doable project?  Has it been done before?

The frequencies aren't too high, so couldn't the top bar be done by
cutting out the luminance for an adjustable time period after each 
vertical blank?  The bottom bar could be controlled by an adjustable 
delay from the last vertical blank until the black begins (cut luma),
after which the luma would remain cut until the cycle repeats.

It would be nice to have the black begin at horizontal sync to avoid a
jagged edge, but this isn't ESSENTIAL.


Comments?  Suggestions?


Mark Fontana

Newsgroups: sci.electronics
From: miked@syscon.rn.com (Mike DeMetz)
Subject: Stepper motor ICs
Organization: Syscon Corporate Headquarters - South Bend, IN USA
Date: Thu, 19 Nov 1992 16:47:19 GMT
X-Newsreader: TIN [version 1.1 PL6]


Does anyone know a mail order place like Jameco or Digi-Key that
carries either the Signetics SAA1027 or Sprauge UCN5804 stepper
motor controller chips? I have not found them in Digi_Key's,jameco's,
or NTE's catalogs. Would the Radio Shack 'order any IC' service be able
to get them?
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Newsgroups: sci.electronics
Subject: VGA monitor repair question
Date: 19 Nov 92 03:49:57 GMT
Article-I.D.: athena.1992Nov19.034957.3328
Distribution: usa
Organization: AI Programs, University of Georgia, Athens

What are the failure-prone components in a monochrome VGA monitor?

Our department was given an IBM 8507 large-screen VGA monitor.
I've been told it's "dead" (no power) but have not tried it out.

I'm pretty experienced with electronics generally but not with monitors,
and it looks as though I'll be going at this one without a schematic.
Can anyone tell me what the most failure-prone parts are, and where to
start looking for the cause of the problem?

Thanks.

-- 
:-  Michael A. Covington     internet mcovingt@uga.cc.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
Newsgroups: sci.electronics
From: patw@cserver.plexus.com (Pat Wilson)
Subject: Re: Cable TV Rules
Organization: Plexus Corp. -- Neenah Wisconsin
Distribution: na
Date: Fri, 20 Nov 1992 18:37:40 GMT

kbass@gmuvax2.gmu.edu (Ken Bass) writes:
>Hookup to me means paying for them to hook up externally. If the give me
>two wires, sure Ill pay. But if I split the signals inside with my
>power, they dont deserve anything.

But, if the cable company can detect that you have split their signal,
there is nothing stopping them from removing their connection.  Especially
if you have signed a contract with them which you are in violation of.
What they deserve means nothing.  What you will pay for their services
means everything.
From: lauren@cv.vortex.com (Lauren Weinstein)
Newsgroups: sci.electronics
Subject: Re: Is lead solder bad for me? (also, silver solder)
Date: 20 Nov 92 06:10:28 GMT
Organization: Vortex Technology, Topanga, CA, U.S.A.

Greetings.  The mention of silver solder triggered an old memory which
may or may not be relevant.  I seem to recall reading that silver
solder was definitely to be avoided for electronics work, and that
some kinds of silver solder use a flux which definitely *is*
toxic (the memory says "cadmium") rather than the rosin flux used
in typical tin/lead solder formulations.

--Lauren--