HDTenEightyP/NetNews huggingface dataset:
From: kranburg@hlunx3.uto.dec.com (Otto van Kranenburg)
Subject: Re: Infrared remote controls
Reply-To: kranburg@hlunx3.uto.dec.com (Otto van Kranenburg)
Organization: Digital Equipment Corporation
Date: Tue, 15 Dec 1992 12:36:39 GMT

The infrared signals being transmitted by IR controls are a series of 1 and 0's
superimposed over a 40 KHZ carrier. The Radio Shack device (if it is the Sharp
GP1U52X-module I think it is) filters out the carrier and leaves you with the
series of 0 and 1's. If you count the pulses and plots them out you will
see the
differences in signals between various brands of equipment. Sony
re-transmits
the same basic signal a number of times while some other brands do it
just once.

Somewhere on the net there is a description of a device referred to as
the Xanadu
Zapper which when connected to the parallel port on a PC can read in the
signals and
play them back.  There are no source listings in the article allthough
some hints are
given how to program.  On output the point is to again add in the 40 KHz
carrier .

In a German PC magasin of last year there was also an article describing
a similar
device with again only some basic programming hints. I 've built a
device which 
actually combines  the schematics for the Zapper and the German
equivalent and
wrote several drivers. On input I' m sampling (at 80 Khz)  app. 40000
pulses
which in all cases was a sufficent number. I then analyse the signal and
in the end
it requires me to store only about 500 integers (I've have to remember
only the 0-1 
and 1-0 status changes). For Sony devices it must either be 6 times more
of I have to
remember to repeat the signal 6 times on output. On output I reconstruct
the original
signal and do a replay at exactly the same frequency as used on sampling
(with the
carrier added in).

Anyway I've succesfully used the device to reproduce the output for 4
different type 
of remote controls. The disadvantage of the way I've done it is of
course that I have to 
store all the signals.

Allthough I 've taken another approach I do remember that in the German
magasin they
did built an output only device as well and programmed it with pulse
information obtained
from Sony.

Hope this is of help,
Otto


-
*****************************************************************
**  Name : Otto van Kranenburg           Organisation: 
**  Email: kranburg@hlunx3.uto.dec.com   Digital Equipment BV
**                                       P.O.Box 8810
**  Tel (Office): 31 10 453 8213         3009 AV Rotterdam
**  Tel (Home  ): 31 78 510 245          The Netherlands
*****************************************************************
Newsgroups: sci.electronics
From: neal@cmptrc.lonestar.org (Neal Howard)
Subject: Re: Radio Isotope Battery?
Date: Fri, 11 Dec 1992 01:08:28 GMT
Organization: CompuTrac Inc., Richardson TX

In article <447@blue.cis.pitt.edu> fmg@alpha.smi.med.pitt.edu (Filip Gieszczykiewicz) writes:
>
>	P.S. Anyone selling pure Li? I'd love to see what would happen
>	if I were to flush a few ounces down the toilet ;-) 

Pure Li can be found at chemical lab supply places (most don't sell to
individuals anymore due to liability problems for those folks that might blow
themselves up or try to make drugs). Li is nothing compared to pure sodium or
even worse, pure potassium (which explodes extremely violently upon contact
with water... it busts the water molecules up and forms H2 gas and potassium
hydroxide at such a high temperature that the H2 gas combusts spontaneously).
My dad used to work for an oilfield machine shop where they had a machine that
used pure potassium (normally stored under oil, kerosine) and water to split
heavy steel pipes apart with.

-- 
=============================================================================
Neal Howard   '91 XLH-1200      DoD #686      CompuTrac, Inc (Richardson, TX)
         "Let us learn to dream, gentlemen, and then perhaps
          we shall learn the truth." -- August Kekule' (1890)
=============================================================================
From: jfw@ksr.com (John F. Woods)
Newsgroups: sci.electronics
Subject: Re: Ranking the Electronic magazines.
Date: 14 Dec 92 12:28:18 EST

And another:

Circuit Cellar INK		Focuses on microcontrollers,
				home automation, and other
				hardware applications.  What
				Steve Ciarcia went and did when
				he got bored with BYTE.
Newsgroups: sci.electronics
From: bill@pauli.lv-physics.nevada.edu (Bill ODonnell)
Subject: Re: Testing solar cell performance w/computer assistance?
Keywords: Solar cell
Organization: UNLV Department of Physics
Date: Mon, 14 Dec 92 22:34:24 GMT

     If extreme accuracy isn't a major concern you may
want to consider using the game port on the Apple.  The
Apple II series and the Apple IIGS both use a 4 channel
A/D converter to read the voltage (via a variable resistor)
at the game port.

     You can read the value of the input voltage in basic with
the following command.

                    X = PDL(N)

N is from 0 to 3 and determines which channel is to be read.
X is the returned value (0 - 255).  The pinouts are as follows:

                    Apple II (16 pin socket)

     Pin #     Description         Pin #     Description
     1         +5 Volts            9         NC
     2         Switch 0            10        Paddle 1
     3         Switch 1            11        Paddle 3
     4         Switch 2            12        Annunciator 3
     5         Strobe Output       13        Annunciator 2
     6         Paddle 0            14        Annunciator 1
     7         Paddle 2            15        Annunciator 0
     8         Ground              16        Nc

                    Apple IIGS (DB9 connector - External
                             or 16 pin socket - Internal)
     Pin #     Description
     1         Switch 1
     2         +5 Volts
     3         Ground
     4         Paddle 2
     5         Paddle 0
     6         Switch 2
     7         Switch 0
     8         Paddle 1
     9         Paddle 3

     Note:     Max current from 5V supply <100ma.
               Switches are TTL inputs.
               Annunciators are TTL outputs.

As for measuring the fill factor I would recommend using a op-amp
as a current to voltage converter for the cell current and also
using and op-amp as a buffer for the cell voltage.  The gains
should be such that the max voltage is near 5V (the A/D reference
voltage).  Suitable scaling factors can then be calculated.  One
final note, although the returned value (0 - 255) would imply 8 bit
accuracy, I would expect accuracies of only a few percent.

						Bill O'Donnell
						(concerned citizen)
From: dplatt@ntg.com (Dave Platt)
Newsgroups: sci.electronics
Subject: Re: Looking for MC3363
Date: 18 Dec 92 21:20:27 GMT
Distribution: usa
Organization: New Technologies Group, Inc.  Palo Alto CA

>What sort of luck have "just normal people" had with distributors
>that take credit cards and have semi-reasonable minimums like
>Arrow, Allied and Newark?

I've had excellent luck dealing with Digi-Key.

Re Allied - I haven't dealt with them directly, but did purchase some
chips and other goodies from Hall-Mark (Allied's parent company).  It
was less convenient than dealing with Allied - Hall-Mark shipped COD so
I had to cut a check for them and have it waiting at the front desk...
but I got everything I ordered in a timely fashion.  Since Allied can (I
was assured) special-order any part which Hall-Mark carries, I'll
probably order through them next time.

-- 
Dave Platt                                                VOICE: (415) 813-8917
              Domain: dplatt@ntg.com      UUCP: ...netcomsv!ntg!dplatt
 USNAIL: New Technologies Group Inc. 2470 Embarcardero Way, Palo Alto CA 94303
Newsgroups: sci.electronics,sci.energy,rec.autos.tech
From: pngai@adobe.com (Phil Ngai)
Subject: Re: Flywheel batteries as EV power source
Organization: Adobe Systems Incorporated
Date: Tue, 15 Dec 1992 19:45:58 GMT

In article <1992Dec15.004956.465@mtu.edu> cmwolf@mtu.edu (christopher m. wolf) writes:
>The same flywheels are referenced in the last IEEE.  They are low mass, very 
>high speed devices.  The low mass does not obstruct cornering, while the
>high speed and low diameter helps them to store more power.  They supposedly
>should take about 10 minutes to fully "charge", given a large enough (not
>impossible) power source, although usually not available in the normal home.
>They should be made of a composite fiber material, so if they should break 
>apart, they will basically turn into something resembling cotton, instead of

But how hot would this "cotton" be? You're dumping what is presumably
the equivalent of several gallons of gasoline's worth of energy.
That's a very large amount of energy.

After all, a Fuel-Air-Explosive is nothing more than some hot gas...

Gasoline powered automobiles don't usually explode on impact despite
what you see in the movies. Flywheel powered vehicles seem a lot more
risky to me.

I hope they do lots of crash tests before unleashing such a dangerous
technology on the unsuspecting public.

Can you imagine the bumper stickers:

	CAUTION: FLYWHEEL ONBOARD

-- 
My opinions are my own.
From: mberg@dk.oracle.com (Martin Berg)
Newsgroups: sci.electronics
Subject: Re: Toroid 60Hz power transformer source?
Date: 17 Dec 92 09:32:00 GMT
Reply-To: mberg@dk.oracle.com (PUT YOUR NAME HERE)
Organization: Oracle Denmark

In article <15DEC199216354453@almach.caltech.edu> shoppa@almach.caltech.edu (TIM SHOPPA) writes:
>Hello,
>	I have been building some low-level audio circuitry, and have had
>problems with hum from nearby AC transformers.  Currently, I have the power
>supply located a great distance away from my circuitry in order to eliminate
>the hum.  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. 

I used to think so, but after building an amplifier using two 500 VA toroid
transformers I am not so sure anymore.
I had several problems with radiated EM fields - one of these resulting in
a 7-9 A (!) current though the chassis.

I have discussed this with one of my friends who works with power supplies
(and transformers) and in his opinion toroid are not as good as originally 
claimed regarding radiation of EM fields.

His experience is that a well constructed 'normal' transformer can be
as good.

Another way to solve your problem could be shielding - enclosing the 
transformer or the low-level equipment in MU-metal (best) or just plain
iron could be a cheep and probably better method to get rid of the EM field.

>	There are several manufacturers of toroidal power transformers,
>but they all seem to want an arm and a leg ($50+) for even the smallest
                                             ^^^^
 This will give you at least a 200 VA toroid transformer here in Denmark.


Kind regards

Martin Berg

Employed by Oracle Denamrk, but this reply are my opinions.
Newsgroups: sci.electronics,comp.robotics
From: cs911225@ariel.yorku.ca (KEN E WILLMOTT)
Subject: Re: Infrared remote controls
Organization: York University, Toronto, Canada
Date: Sat, 12 Dec 1992 18:33:28 GMT

>>    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.

>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

If you do this, remember that a transmit packet from a normal
handheld transmitter is preceded by a whopping long "on" pulse,
to allow the receiver's AGC circuit to stabilize.

	-Ken
Xref: sparky sci.electronics:20920 sci.energy:6175 rec.autos.tech:16789
From: bj368@cleveland.Freenet.Edu (Mike E. Romano)
Newsgroups: sci.electronics,sci.energy,rec.autos.tech
Subject: Re: Flywheel batteries as EV power source
Date: 17 Dec 1992 05:21:49 GMT
Organization: Case Western Reserve University, Cleveland, Ohio (USA)
NNTP-Posting-Host: hela.ins.cwru.edu


This flywheel discussion is interesting.
I am not an engineer but note it was mentioned that a proper
size flywheel can store the energy/power of a v8 engine.

What is the simple equation here for energy (horsepower) stored
in say a flywheel weighing 200 pounds, spinning at  1000 rpm?
My last physics course was in high school.


-- 
Capt. Kirk: let's head for that planet, third from the sun, it
            looks promising.... |-)
From: raju@bass.bu.edu (Rajminder Singh)
Newsgroups: sci.electronics
Subject: Motion Sensors - how do they work ?
Date: 20 Dec 92 05:05:01 GMT
Reply-To: raju@bass.bu.edu (Rajminder Singh)
Followup-To: sci.electronics
Organization: Boston University

Hi,
	I was just curious to know how motion sensors work ? We have one
installed in our lounge which turns the lights 'On' when someone enters the
room. If someone moves in the lounge, an LED mounted on the sensor turns on
and goes off as soon as the movement is stopped - is this a pressure
transducer at work ?
	
Rajminder Singh
From: jmce+@andrew.cmu.edu (James Ryan Miller)
Newsgroups: sci.electronics
Subject: PADS Shareware Installation
Date: 12 Dec 92 15:13:00 GMT
Article-I.D.: andrew.of_csQK00iUy83m1h4
Organization: Freshman, CIT general, Carnegie Mellon, Pittsburgh, PA


    I've got a number of requests for the info on how to get PADS to
install, so here it is.  Any problems with this, just let me know.

                                        Ryan Miller
                                        jmce+@andrew.cmu.edu

------
PADS logic and PADS pcb manual installation

        Many people have had trouble running the install program for
these programs.  Then you must install the programs manually as follows:

1)      You need these files:           PADSPCB.ZIP
                                        PADSLOG.ZIP
                                        PADSLIB.ZIP

        make the directory:             /PADSDEMO

        unzip PADSLOG.ZIP into the \PADSDEMO directory, and copy the
file files.exe to logfiles.exe.  Then unzip the other two into
\PADSDEMO.

2)      Make the following directories: /PADSDEMO/LOGFIL
                                        /PADSDEMO/FILES
                                        /PADSDEMO/LIB
                                        /PADSDEMO/CAM

3)      Move the following files:
        \PADSDEMO\LIB.EXE       ->      \PADSDEMO\LIB\LIB.EXE
        \PADSDEMO\ULIB.EXE      ->      \PADSDEMO\LIB\ULIB.EXE
        \PADSDEMO\FILES.EXE     ->      \PADSDEMO\FILES\FILES.EXE
        \PADSDEMO\LOGFIL.EXE    ->      \PADSDEMO\LOGFIL\LOGFIL.EXE

4)      Execute the following files (they are self extracting):
                \PADSDEMO\PADS.EXE
                \PADSDEMO\DHLP.EXE
                \PADSDEMO\LOGIC.EXE
                \PADSDEMO\LIB\LIB.EXE
                \PADSDEMO\LIB\ULIB.EXE
                \PADSDEMO\FILES\FILES.EXE
                \PADSDEMO\LOGFIL\LOGFIL.EXE

5)      Okay, the program installation is done.  You must do hardware
setup still.  Goto the \PADSDEMO directory and run pinstall.

        That should be it.  I hope this helps.  Let me know if you have
any problems.

                                                Ryan Miller
                                                jmce+@andrew.cmu.edu
Xref: sparky sci.electronics:21066 sci.energy:6233 rec.autos.tech:16861
From: jhaines@eniac.seas.upenn.edu (Jason Haines)
Newsgroups: sci.electronics,sci.energy,rec.autos.tech
Subject: Re: Flywheel batteries as EV power source
Date: 18 Dec 92 03:20:37 GMT
Followup-To: sci.electronics
Organization: University of Pennsylvania

In article <1992Dec18.012654.26238@ra.oc.com> rodder@ccwf.cc.utexas.edu (Jon D. Rodder) writes:
>In article <1992Dec17.011649.987@cmkrnl.com> jeh@cmkrnl.com writes:
>>
>>Then we come to electric motors to drive the wheels.  Electric motors have
>>wonderful torque/speed characteristics for vehicles (they generate maximum
>>torque just before stall speed, which may make transmissions and clutches
>>unnecessary) but lousy power density -- look at the size of a 1-hp. electric
>>motor sometime and tell me how big a motor would have to be to accelerate a
>>car fast enough to keep up with gasoline-powered ones.  
>>
>>Internet:  jeh@cmkrnl.com, hanrahan@eisner.decus.org, or jeh@crash.cts.com
>
>Well, lets see..  the 20hp permanent magnet motor in our solar powered car
>is about 6 inches in diameter and 6 inches long.  It weighs under 20lbs.
>See the GM Impact for a production style example of a compact high power
>motor.
	I was waiting for someone to reply to this comment (I lost the
original message).  The 20hp DC brushless motor in our solar
car is also about 6" in diameter and less than 6" (not counting the cooling
fan and wiring set-up attached to the side) long.    I haven't weighed the
motor recently so this is from memory but I thinkj it weighs about
30 lbs.  Sounds pretty compact to me - plus it delivers virtually all
of its torque at 0 rpm and continues to have virtually constant 
torque charactericts for a much broader range than any IC engine.

>-=<   Jon Lusky ----- rodder@ccwf.cc.utexas.edu   >=-- 


------------------------------------------------------------------------
Jason R. Haines		     University of Pennsylvania (SEAS & Wharton)
------------------------------------------------------------------------
   Red '90 Mustang LX 5.0    /     Blue '71 Rotary Powered Datsun 510
(Recycle your toner cartridges)	           (^^^^^FOR SALE^^^^^)
------------------------------------------------------------------------



Newsgroups: sci.electronics
From: keithl@klic.rain.com (Keith Lofstrom)
Subject: Re: How full is a nicad
Organization: Keith Lofstrom Integrated Circuits
Date: Sat, 19 Dec 1992 23:01:12 GMT

In article <BzD705.C94@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>In article <1992Dec15.103954.6299@quando.quantum.de> henigan@quando.quantum.de (Kevin Henigan) writes:
>>I believe you can tell how full a nicad is from it's Voltage...
>
>No, you can't.  This is one of the fun problems of building a NiCd charger.
>The output-voltage curve of a NiCd is essentially flat from pretty nearly
>full charge to pretty nearly empty.

There are many applications where knowing the charge on the battery is 
crucial.  Given my rudimentary knowledge of electrochemistry, it would
seem that one could provide a third electrode on a battery, of some other
materials than the main electrodes, designed to indicate the balance of
electrolytes in the cell.  It might even be possible to detect battery
health as well as charge.  I could imagine building a really cheap IC
that could measure the pulsed characteristic curves of this third electrode,
and give a readout of battery condition, or control information to a charger.

Any electrochemistry buffs out there who can comment intelligently?

Keith
-- 
Keith Lofstrom         keithl@klic.rain.com       Voice (503)-520-1993
KLIC --- Keith Lofstrom Integrated Circuits --- "Your Ideas in Silicon"
Design Contracting in Bipolar and CMOS - Analog, Digital, and Power ICs
From: urbina@novax.llnl.gov
Newsgroups: sci.electronics
Subject: Secure voice telephony: technical questions
Date: 19 Dec 92 04:13:41 GMT


I'm building my own secure voice telephony (digital speech scrambler ) and I
would like to use it over the telephone. I've some questions for any of you
Telcom or DSP type people or anybody that's done this before.

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.

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
tone, the 567's both send a low out to a NOR gate 74LS02 which sends out a high 
which enables the 74LS164 shift registers that create the pseudonoise.
The high from the 74LS02 also gets routed through an inverter which then goes
to a low which enables the chip select lines on the ADC's and DAC's.

Ideally, both calling and receiving parties will detect the #7 digit at the
same time and therefore be synced up. I haven't built up this part of the
circuit yet, but it looks good on paper. Any of you guru types see any problems
with this please let me know.

3.) I've heard of all this talk about 1 bit ADC's DAC's, Sigma Delta
converters, Pulse code modulation. Are these converters more appropriate for my
design ? Do I still have to sample at twice the bandwidth with these converters
to get understandable speech or, are they 1:1 linear type converters ? What is
meant by pulse code modulation ?

4.) I'm more of an analog Pulsed power type of guy, but I'm having a lot of fun
trying to prototype this scrambler. I'll appreciate any help and ideas from
anybody that could save me some time. Thanks.

Guy
Urbina@novax.llnl.gov

Xref: sparky sci.electronics:20896 alt.guitar:10907 rec.music.makers.guitar:969
From: ah335@cleveland.Freenet.Edu (Richard Banks)
Newsgroups: sci.electronics,alt.guitar,rec.music.makers.guitar
Subject: purpose built distortion producing circuits
Date: 17 Dec 1992 00:14:05 GMT
Organization: Case Western Reserve University, Cleveland, OH (USA)
Reply-To: ah335@cleveland.Freenet.Edu (Richard Banks)
NNTP-Posting-Host: slc10.ins.cwru.edu



I'm constructing a purpose built distortion producing circuit to
be used to add gain to audio signal of an electric guitar.

The circuit uses 4 stage op amp noninverting configuration to
produce a gain of 1855 running off a 9V power supply.

My problem is the unit is acting like a noise gate, when the signal
attenuates the circuit "cuts off."  Therefore it is very quiet,
but does not produce long sustain, which is what I want.

The value of the feedback resistors are 100k and the value of the
power resistors is 220 ohm.  Could it be that I should
increase the value of the feedback resistor and raise the
value of the power resistor but so that it still produces the
same amount of gain at each stage? 
I was thinking maybe my problem was that the signal was
getting "drained" by the power supply because of the low
power resistor value.

If you have any other ideas or suggestions please present them to
me.  Thanks.


Also on a side note, what is the best op amp config to use
for distortion, inverting or noninverting?

I would think noninverting, because inverting amps cause
a lot more bias current at high gain.
But Craig Anderton uses inverting amps for almost all his
signal processing designs in his projects book.
Even for the distortion circuits.

Thanks in advance.
Rich Banks.
Xref: sparky sci.electronics:21162 rec.aviation:17554