HDTenEightyP/NetNews huggingface dataset:
Newsgroups: sci.electronics
Subject: Yamaha Chip STK3042 III
Date: Sun, 13 Dec 1992 03:43:10 -0600

MR>From: robertso@unpsun1.cc.unp.ac.za (Mike Robertson)
MR>Path: tghost!uuneo!sugar!menudo.uh.edu!zaphod.mps.ohio-
MR>state.edu!uwm.edu!wupost!uunet!psgrain!hippo!ee.und.ac.za!tp
MR>infm
MR>Newsgroups: sci.electronics
MR>Organization: Computer Services Div, University of Natal,
MR>Pietermaritzburg, RSA
MR>Reply-To: robertso@unpsun1.cc.unp.ac.za

MR>Hi,

MR>I'm trying to obtain the amplifier driver chip for a Yamaha
MR>Amp.  The number is STK3042 mark III.  Any ideas?
MR>(Preferably a mail order company!).


MR>Thanks

MR>Mike Robertson                 |  DISCLAIMER: These are *my* thoughts & are
MR>robertso@unpsun1.cc.unp.ac.za  |  thus not necessarily those of the Computer
MR>                               |  Services Div. at the University of Natal

MR>---
MR> * Origin: Fahrenheit 454 -- FidoNet <--> UseNet gateway (1:106/1024.0)

Try
Consumer Electronics Replacement Source Book
Electronic Industries Association PO Box 19100
Washington D.C. 20036
Include $1.00 for postage and handling.

By the way it's much easier to look up a mfg or parts warehouse if you
give the FCC id number.

Of course you could also try Yamaha Electronic Corps. USA
Parts Department
6722 Orangethorpe
Buena Park Ca 90620
714-522-9105
800-854-3264
714-994-3312
fax 800-634-0355
___
 X OLX 2.1 X Proofread carefully to see if you any words out.

Xref: sparky sci.electronics:21227 sci.energy:6284 rec.autos.tech:16963
From: bruce@corona.syd.ips.oz.au (Bruce Paterson)
Subject: Very sharp RF notch filter sought
Originator: bruce@corona.syd.ips.oz.au
Reply-To: bruce@ips.oz.au (Bruce Paterson)
Organization: IPS Radio and Space Services.  Sydney, Australia.
Date: Mon, 14 Dec 1992 06:44:45 GMT

I need a VERY sharp notch filter (or actually 3, if sharp enough) to reject
FM broadcast stations from an antenna signal. The requirements are tough:
a. VERY sharp - I need to measure spectra of broadband noiselike signals and
the present LC filters make a far too visible hole.
b. No other holes (or even ripples) in the pass band - 57 to 180MHz.
c. Low loss.

LC type circuits are not sharp enough. Using a crystal is out as it is too
lossy and has many other smaller holes. A carefully made cavity may be the
answer, but while I can find many ways to use a cavity to reject one
frequency and pass another (standard diplexers), I can't see how to use one
to only reject a frequency, while passing all others. Any help?
Xref: sparky sci.electronics:20969 sci.energy:6197 rec.autos.tech:16811
From: mwilson@ncratl.AtlantaGA.NCR.COM (Mark Wilson)
Newsgroups: sci.electronics,sci.energy,rec.autos.tech
Subject: Re: Flywheel batteries as EV power source
Date: 17 Dec 92 17:27:27 GMT
Organization: NCR Engineering and Manufacturing Atlanta -- Atlanta, GA

In <1992Dec17.035214.15058@u.washington.edu> basiji@stein.u.washington.edu (David Basiji) writes:

|I would design a housing of Kevlar or Spectra woven around a thin lead
|alloy lining. The lead would prevent small particles from penetrating the
|weave by distributing the force over an area larger than the mean cell
|size of the fabric.  The weave would contain any larger particles so that
|the energy would be dissipated within the housing by all the mechanisms
|mentioned before, as well as a considerable portion from particulate
|collisions within the housing.  The housing would be relatively light
|and could be formed into fairly complex shapes. Cost would not be prohibitive
|, probably on the order of $300, with economies of scale.

It doesn't matter how large an area you spread the impact over.

All of the kinetic energy contained in the flywheel, will upon failure,
be converted to heat.  Unless the containment vessel is large enough
to absorb all of that heat without melting, it will fail.  When it
does fail, in addition to the rapidly expanding field of very hot
gas, now you also have to worry about droplets of molten metal.

I wouldn't want to be anywhere near it when it goes off.
-- 
Mob rule doesn't become any prettier, just because the mob start to call itself
a government.
It ain't charity if you are using someone else's money.
Mark.Wilson@AtlantaGA.NCR.com
Newsgroups: sci.electronics
From: nagle@netcom.com (John Nagle)
Subject: Re: Secure voice telephony: technical questions
Organization: Netcom - Online Communication Services  (408 241-9760 guest) 
Date: Sat, 19 Dec 1992 19:35:55 GMT

urbina@novax.llnl.gov writes:
>1.) My design right now incorporates a 14 bit serial output ADC. I sample the
>speech at 7khz which is double the bandwidth of telcom speech. The output from
>the ADC is XOR'ed with a 31 stage linear feedback shift register that generates
>several hours of pseudorandom "noise" before it repeats itself. (It's clocked
>at 7khz to give me that long turn-around time.) This encrypted data stream gets
>sent over the telco line (in theory) and the receiving party whose PN generator
>is synced with mine, decodes the encrypted data stream and the remaining voice
>bits are routed to his/her DAC. My question is 7khz too fast for telcom ?
>I've heard of speeds of 9600 baud with modems. Appreciate any help with this.

       7kHz times 14 bits = 98,000 bits/second.  This is well beyond
existing modem technology.  The usual telephone standard is 8 bits, and the
D/A isn't linear, it has a psuedo-logarithmic response curve to improve
the dynamic range.  There are standard IC for this, called "codecs".

       This still gets you 56Kb, which, in fact, is the rate used in the
digital portions of the telephone system.  But you can't push that through
a modem without some compression.  Most modern cryptosystems compress the
audio down to 9600 or 4800 baud, using linear predictive compression (LPC).
There are ICs for this, too.  Of course, an encrypted ISDN phone would
be much easier; no compression required.  That would be a nice
project.

       Then you need to encrypt.  A 31-bit recirculating shift register
is a very weak encryption algorithm.  Ask in sci.crypt for a better one.

       You might be able to do the whole job in a DSP chip, including the
modem.  That might be the lowest-cost solution; DSP chips are getting cheaper.

>2.) The quick and dirty way I've synced the pseudonoise generators of the
>calling and receiving parties is that I've 2 LM567 tone decoders that monitor
>the telco line for say...the digit 7 (852hz + 1209hz.) When it detects that..

        Using a tone decoder to indicate you want to turn the system on
is fine, but you probably won't get precise enough timing from them to
sync to the 100uS required at even 9600 baud.  Better to send some sync
pattern in the digital data stream and sync up on that.

        AT&T is now selling a real encrypted phone for around $1300,
based on the STU-III technology.  The problem still seems to requires enough
parts to keep the cost high.

        If you're more of an analog person, you might look into Turing's
original analog voice cryptosystem, described in "Turing - the Enigma".
1940s technology, but considered sound by Turing, who furfils the
criterion set down by Friedman: "No new cryptosystem is worth looking at
unless it was invented by someone who has already broken a very hard one."

					John Nagle
From: andy@laguna.santafe.edu (Andy Mell)
Newsgroups: sci.electronics
Subject: Sound -> Movement circuit required
Date: 18 Dec 92 20:32:17 GMT
Organization: Santa Fe Institute

Could someone help me out here please? I'm trying to knock up some sort
of sound -> movement circuit so that I can convert changes in sound
(input at line level) to voltage pulses in order to drive a stepper
motor.

The outcome of all this is a scanning mirror which moves in response to
sound for use in a disco, I like the idea, and would love to build one
rather than buy one as they are rather expensive.

Any clues please? You can email me here or post.

Many thanks.

Andy

-- 
-------------------------------------------------------------------------------
Andy Mell, Applied Physics Department,  |   andy@santafe.edu
University of Hull, Hull, HU7 6RX       |   amell@nyx.cs.du.edu
England.                                |   torq@gnu.ai.mit.edu
From: fmg@alpha.smi.med.pitt.edu (Filip Gieszczykiewicz)
Newsgroups: sci.electronics
Subject: 4 sale: tube radio
Summary: Fisher radio, not really for profit...
Keywords: bit heavy, hence "na" distribution
Date: 15 Dec 92 16:12:03 GMT
Followup-To: sci.electronics
Distribution: na
Organization: Medical Informatics


	[Yes, I know posts like this are frowned at here but it's a bit on
	topic and maybe some folks are interested. I'll never get my money
	back - less make a profit :-]

	Greetings. I recently decided that I'm too young to play with
	tubes... somehow they and system design don't mix ;-) This means
	that I have something some folks may be interested... my The Fisher 
	500-C tube radio. I used it for about 3 years when, during painting 
	my room, someone shattered 2 output tubes. I did order new ones but 
	they went into something else. So, what you get is a working radio 
	with only one output channel working. Also, there is no case (just 
	the bare radio & front panel). I'll take best offer... (be reasonable)
	(and, depending on offer, I might split shipping... ;-)

	Take care.

	P.S. For those that aren't familiar with this radio:
	output tubes: 7591A's (2/channel), tuner uses: 6CW4's,
	nice output Xformers :-), very good reception & selection (comes
	with MPX-65 plug-in)

	Oh, I might as well toss in the rest of my "tube" stuff:
	I have a box of various tubes (might make a list - most in boxes)
	as well as an old Magnavox mono amp (uses 4 6V6's, 25Y3GT's, etc) 
	just to balance the box ;-) If you get the Fisher, and want this, 
	it's free.
-- 
+------------------------------------------+----------------------------------+
| Filip "I'll buy a vowel" Gieszczykiewicz | Best: "fmgst+@pitt.edu"          |
| "If I feel that I've made this world a   | Or: "fmg@alpha.smi.med.pitt.edu" |
| better place, I will die content." - Me  | Ftr wnr f TLJ Rsrch!             |
From: bb099@cleveland.Freenet.Edu (Adam Trent Phillips)
Newsgroups: sci.electronics
Subject: Re: Inductance Question
Date: 15 Dec 92 20:53:26 GMT
Organization: Case Western Reserve University, Cleveland, Ohio (USA)
NNTP-Posting-Host: slc10.ins.cwru.edu


masterov@chiller.ecn.purdue.edu (Michael Masterov) on Dec 15 12:10 1992 posted:
|
|
|For anyone out there - I need help.  I am currently running a volta arc
|from a welding power supply which is supposedly current regulated.  To
|measure the current I am using a scope and a shunt (the supply is not
|filtered so there is a waveform to observe ) with a shunt resistance
|of 5 milliohms.  Specified current is 20 Amps.  The waveform I am
|getting is non-sinusoidal and has an rms value around 300 milliVolts.
|
|Note - I am not an EE.  I am lost.  Anyone out there with a clue?
 
 
	I would suggest using a larger shunt, perhaps 4x (?) the
present. Then use the following ckt.
 
          shunt
---------/\/\/\/\/\---------
        |          |
        |          |
        |          |
  |------------------------|
  |     ~          ~       |
  |   (BRIDGE RECT.)       |
  |                        |   Br1
  |     +          -       |
  |________________________|
        |          |
        |          |
        |    C1    |
        |----||----|
        |          |
        |          |
        to scope
 
	C1 5uF might be good...experiment to get a good smooth DC waveform
        If there is a polarity on the cap MAKE SURE IT IS CORRECT!
        electrolytics are polarized, if you get it backwards it might explode
	also observe the MAX voltage indicated on the cap and make sure it
	can handle about 2x the voltage coming out of the bridge
 
        shunt: 4x might do the trick. Try to get approx. 5-10v across the
        shunt. Keep in mind too, the diodes in a bridge rect. have a .6-.7v
	drop accorss them while conducting
 
	The Bridge rect. will convert the ac/dcsp/dcrp to what you KNOW
	is DC. Then the Cap. will smoothen the DC. 
 
	Also, if you run DCRP or DCSP it wil keep the polarity 
	consistent at the scope end.
 
 
	This is off the top of my head and you did not say if this was a 
TIG,MIG or SMAW welder.
 
 
	Lincoln Electric or Arco might have some Ideas. They make many of
the welders out there.
 
-- 
A. TRENT PHILLIPS |" A mirror is a negative space with a frame and a place for
  also known as   | your face, it reveals what the rest of us see. It conceals
   WHITE  ROOK    | what you'd like you to be."--Blue Oyster Cult
-------bb099@cleveland.freenet.edu-----aa1439@freenet.lorain.oberlin.edu-------
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Newsgroups: sci.electronics
Subject: Re: Ranking the Electronic magazines.
Date: 14 Dec 92 05:55:23 GMT
Organization: AI Programs, University of Georgia, Athens

Computer Craft today is what Byte was in the 1970s -- the computer
_tinkerer's_ magazine.  It concentrates on fairly easy-to-build
interfacing gadgets and beginner-level microcontroller projects.
It's a good magazine and occupies a niche that no other magazine does;
it has no direct competition in the USA.

-- 
:-  Michael A. Covington     internet mcovingt@uga.cc.uga.edu :   Verbum caro
:-  Artificial Intelligence Programs       phone 706 542-0358 :    factum est
:-  The University of Georgia                fax 706 542-0349 :  et habitavit
:-  Athens, Georgia 30602-7415 U.S.A.     amateur radio N4TMI :   in nobis...
Newsgroups: sci.electronics
From: ornitz@kodak.kodak.com (Barry Ornitz)
Subject: Re: Toroid 60Hz power transformer source?
Followup-To: sci.electronics
Summary: Wind it yourself
Organization: Eastman Chemical Company
Date: Wed, 16 Dec 92 17:01:02 GMT

In article <15DEC199216354453@almach.caltech.edu> 
shoppa@almach.caltech.edu (TIM SHOPPA) writes:
>The sort of transformer I need is 120VAC to around 20 VAC
>center-tapped, at a few V-A's. As I understand, Toroid transformers can have a
>much smaller radiated EM field than usual transformers. 
>	There are several manufacturers of toroidal power transformers,
>but they all seem to want an arm and a leg ($50+) for even the smallest
>transformers.  Does anyone know of a more inexpensive source for these?
>Alternatively, is winding my own toroidal transformer out of the question?
>I have wound several RF toroidal transformers, but I imagine that a totally
>different core material would be used in a 60 Hz transformer, and saturation
>of the core would be a big concern.  Do any toroidal core manufacturers
>give information on using their cores in 60 Hz transformers?  I'm looking
>for the sort of information Amidon gives on their cores - sort of a cookbook
>procedure on how to make your own transformer.

A quick and dirty approach would be to get a toroidal variable transformer
(Powerstat, Variac, etc.) and wind the appropriate secondary on it.  Our
lab chemists routinely destroy small Variacs used to power mantles and heating
tape. [It is nearly impossible to teach them to use the correct fuse size! ;-) ]
I have quite often repaired these units for home use and used them as the
primary for custom transformers.  Count the turns on the original transformer
to get the turns per volt rating and wind your secondary to your needs.  I use
glass cloth tape the insulate the original Variac.  Watch out to not exceed
the VA rating of the transformer. [Most of our lab units are 1 KVA.]  Also
be very careful of your insulation ratings.  You do NOT want a primary to
secondary short!
					Barry
 -----------------
|  ___  ________  |    Dr. Barry L. Ornitz          WA4VZQ
| |  / /        | |    Eastman Chemical Company
| | / /         | |    ECC Research Laboratories, Engineering Research Div.
| |< < K O D A K| |    Process Instrumentation Research Laboratory
| | \ \         | |    P. O. Box 1972, Building 167B
| |__\ \________| |    Kingsport, TN  37662  (615/229-4904, FAX 615/229-4558)
|                 |    INTERNET:   ornitz@kodak.com
 -----------------
Xref: sparky sci.electronics:20783 rec.audio:16743 alt.guitar:10877 rec.music.makers.guitar:944
Organization: Stanford Linear Accelerator Center
Date: Tuesday, 15 Dec 1992 13:34:06 PST
From: <WAUGH@SLACVM.SLAC.STANFORD.EDU>
Newsgroups: sci.electronics,rec.audio,alt.guitar,rec.music.makers.guitar
Subject: Re: Electric Guitar Pickups?

In article <BzBHy8.G8o@ns1.nodak.edu>, jhalvers@plains (Jon Halverson) says:

   (stuff about passive pickups deleted)

> Active pickups are another story. Basically what they are is a very low
>imp. pickup with a built in pre-amp. The signal therefore is much cleaner.
>The output voltages are usually set up to match reg. pkups.

How do today's active (low impedence) pickups compare with those low impedence
jobs seen on old "recording" guitars put out by Gibson and others.  The L-5S
and the Les Paul both came in low impedence versions.  These generally have
lower market value than their humbucking counterparts.  Might these oldies be
fitted with an internal pre-amp and be used with regular amps?

Brian
Newsgroups: sci.electronics
From: brown@ccit08.duq.edu (Jason Brown)
Subject: Band pass filters
Organization: J. Random Misconfigured Site
Date: Fri, 18 Dec 1992 13:33:46 GMT
X-Posted-From: ccit08.duq.edu
NNTP-Posting-Host: sol.ctr.columbia.edu


Here's a question from a computer scientist (EE wanna-be) who likes to  
tinker.  Lately I've been building things with logrithmic dot/bar display  
drivers. (You know how Computer Scientists love flashing lights :-)).   
Anyway, it occurs to me that using some combination of resistors and  
capacitors in an RC circuit one should be able to filter out all but a  
given frequency from an analog audio source.  The ultimate goal here would  
be to set up a number of filters at different freqs. and send the output  
of these filters to log. dot/bar display drivers yielding a spectrum  
analyzer.

Can someone illuminate me as to how figure out what values to use to get a  
specific frequency isolated?

thanks in advance.


--
   ____               ___
    /                 /  )
   /  _, ,  __       /-,' ,_  __
\_/__</_/>_(_/_/\/  /__)__/__(_/__(_/_)_/\/

"Remember, be humble, always answer the phone...
 No matter who's in the car." - Jack Lemmon
From: stansbury-travis@yale.edu (Travis Stansbury)
Newsgroups: sci.electronics
Subject: Anyone know what a C457OHA is?
Date: 17 Dec 1992 00:41:35 -0500
Organization: Yale University
Distribution: usa
NNTP-Posting-Host: minerva.cis.yale.edu


I had my CD player apart trying to locate the output opamps, hoping that
substituting better ones would be a simple matter.  All I found that
might be the right things were two six pin (single row - looked like a
resistor array) IC labelled "C457OHA"  also there was a "88O7N" on
them... might this be the op amp, and if so, is is pin compatible with
the popular replacement opamps?  Oh, the CD player is a Nak OMS1A.
Thanks..
-- 
   ______________________________________________________
   | Travis Stansbury, Yale '94  || 2358 Yale Station   |
   | travis@minerva.cis.yale.edu || New Haven, CT 06520 |
   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From: mpaul@unlinfo.unl.edu (marxhausen paul)
Newsgroups: sci.electronics
Subject: Re: Panasonic Printers with PADS?
Date: 14 Dec 1992 20:28:20 GMT
Organization: University of Nebraska--Lincoln	
Distribution: global
NNTP-Posting-Host: unlinfo.unl.edu

mpaul@unlinfo.unl.edu (marxhausen paul) writes:

>Does anybody know what the optimal printer setting is when using PADS
>software with the popular Panasonic KXP-1124/1124i?  It works when

Ah, shoot, I'll answer my own question.  (Read the *** printer manual,
dude.)  Set the printer as an EPSON LQ-800 and your Panasonic KPX1124
will be happy and give you very nice printouts - wouldn't want to fabri-
cate a PC board from it but plenty good for all other purposes.

--
paul marxhausen .... ....... ............. ............ ............ .......... 
 .. . .  . . . university of nebraska - lincoln .  . . .. . .  .. . . . . . . .
 .     .    .  .   .     .   .  .    .   .  .   .    .   .  grace .   .    .  . 
   .         .       .      .        .        .      .        .   happens .
From: jhwhit01@ulkyvx.louisville.edu
Newsgroups: sci.electronics
Subject: Re: INTEL 8052 w/BASIC - is the code public domain?
Date: 15 Dec 92 20:56:06 GMT
Organization: University of Louisville

In article <1992Dec15.175451.19971@hou.amoco.com>, zklf0b@gs144.hou.amoco.com (Fergason) writes:
> In article <533@bit.UUCP> thomas@bit.UUCP (Thomas Walter) writes:
>>Does INTEL still supply the 8052BASIC chip?
> 
> dont know.
 
The 8052AHBASIC is listed in the 1993 Jameco catalog for $24.95 each.  It is
part number 52011.  If the BASIC source is available from Intel, you might get
by cheaper with the 8052AH, part number 52003, and an EPROM.  The 8052AH lists
for $5.95.  The 8073, part number 52038, is $6.95 and comes with a Basic Micro
Interpreter built-in.
 
Jameco ServiceLine is 1-800-831-8020.  Technical Support is 1-800-831-0084.
Order Toll Free 1-800-831-4242.  FAX 1-800-237-6948.  If the toll free numbers
don't work, call 1-415-592-8097 from 7am-5pm PST.  Here is a mail address:
 
Jameco Electronic Components
1355 Shoreway Road
Belmont, CA  94002
 
Jeff White    jhwhit01@ulkyvx.bitnet
Xref: sparky sci.electronics:20556 comp.robotics:2623
From: cmcmanis@pepper.Eng.Sun.COM (Chuck McManis)
Newsgroups: sci.electronics,comp.robotics
Subject: Re: Infrared remote controls
Date: 12 Dec 1992 07:42:59 GMT
Organization: Sun
NNTP-Posting-Host: pepper

In article <of90_cC00UhB465rsp@andrew.cmu.edu> jmce+@andrew.cmu.edu (James Ryan Miller) writes:
>
>    I am trying to find information on how infrared tv remote controls
>send signals.  I have one of those infrared receivers from Radio Shack
>hooked up to my 68HC11EVBU board, and have been experimenting with
>trying to program it to read the buttons off a remote control for a Sony
>Trinitron tv.

If you can find an older General Instrument catalog, look up part
AY-3-8470 this is an infrared transmitter chip. There is also a receiver
equivalent. Anyway, besides the interesting tidbits on IR receivers
they use a code whereby they send the 8 bits of data, and then send
the 8 bits inverted, this 'double' byte allows the receiver to
differentiate between spurious inputs and real signals. 

Other interesting references :
	"Use Infrared Communication for Remote Control", Steve Ciarcia,
	BYTE April '82, and Ciarcia's Circuit Cellar Volume IV.

	"The Robot Builder's Bonanza", Gordon McComb, published by
	TAB books Pg 255-261. ISBN #0-8306-2800-2


However the absolutely best advice I can give you is to stop trying
to figure out the Sony remote. Instead, wire up an infrared diode
and a uart and that you can use to "train" one of these programmabe
remotes (I got one from Radio Shack for $30 on sale once). Then you
can design your own protocol pretty much and you always know what the
transmitter will send when you hit the "1" key. :-)



--
--Chuck McManis						    Sun Microsystems
uucp: {anywhere}!sun!cmcmanis   BIX: <none>   Internet: cmcmanis@Eng.Sun.COM
NIS+ Architect
These opinions are my own and no one elses, but you knew that didn't you.
Xref: sparky sci.electronics:21240 rec.autos.tech:16977 sci.energy:6297