HDTenEightyP/NetNews huggingface dataset:
From: mgc@unislc.uucp (Marc Christensen)
Subject: Re: microcontrollers
X-Newsreader: TIN [version 1.1 PL6]
Organization: Unisys Corporation SLC
Date: Thu, 12 Nov 1992 17:54:14 GMT

Ronald A. Huizar (rahhelp@rigel.tamu.edu) wrote:
: 
[Text Deleted]
: 
: One problem that I am already see is that the microcontroller I was
: planning to use the MC68HC811E2 can only address about 64K of external
: memory, and we are planning/contemplating storing the message
: digitally. I have not had much DSP, my partner has had more than I,
: but I figure that for the telephone we will need to sample at least
: 6000 Hz (since the phone BW is 30-3000, you remember Nyquist don't
: you). For a 1 minute (kinda long I know) message that will require
: about 3 Meg of memeory. To much for the E2. So I know that the
: microprocessors can handle the amount of memory I would need but I did
: want to have build my own computer first.
: 
Your numbers for the reqd memory sounds high.

         6000 samples/second at 8 bits resolution.  I think 4k/sec is 
              understandable but quality does suffer.
           60 seconds
    --------- 
       360000 about 360k/minute      	

3 meg should give you just over 8 minutes.
64k gives 10 sec. so you still need more memory or real short messages
: 
: Is there some sort of MCU available that can address enough space for
: me to build this device? I have heard about Motorola having a new
: improves MCU that was 32 bits. Is this true, does anyone have any part
: numbers and/or prices.
: 
I have the data books for the larger MCU's from motorola at home and if I 
remember correctly they are compatible with the 68000 line except for about
6-8 functions short and have several added specific to MCU needs. This may 
make it possible to do most of your design and testing on a 68XXX machine
then just port it to your project.

I can get you more info after I get back from COMDEX in a littlr over a WK.
someone else probably can get you the info quicker. you could call Motorola
and they will give you a list of your local distributors. One of them should
GIVE you the databooks if you tell them about your project, esp. if you leave
the student part out. 
you will probably get a lot better price buying a few parts "for design and
 testing purposes" than "What would a price be on one unit?"

Marc Christensen
From: kludge@grissom.larc.nasa.gov (Scott Dorsey)
Newsgroups: sci.electronics
Subject: Re: doherty@melpar R DETECTOR TUBE WANTED
Date: 6 Nov 1992 17:50:22 GMT
Organization: NASA Langley Research Center and Reptile Farm
NNTP-Posting-Host: grissom.larc.nasa.gov

In article <1ddrj5INNrl5@clover.csv.warwick.ac.uk> cstadbg@csv.warwick.ac.uk (Mr M J Brown) writes:
>----------------------------------------------------------------------------
>
>To: doherty@melpar
>Subject: Re: IR detector tube wanted
>Newsgroups: sci.electronics
>In-Reply-To: <Bx8soG.BrD@melpar>
>References: <1d5rgeINN9v6@clover.csv.warwick.ac.uk>
>Organization: Computing Services, University of Warwick, UK
>
>That price sounds a bit steep...I did hear mention of around 99 dollars
>for a 6032 type tube... maybe there are two types of tube, what I want
>is just the glass tube bit....I can make up case/EHT psu etc. myself.

The IR tubes are much, much cheaper than the starlight tubes.  You can
get a complete (Israeli surplus) stereoscopic IR viewer for about $500;
our local cine film lab has a dozen sets for their darkroom workers.  The
starlight viewers are much, much more expensive.
--scott
From: steuer@clam.rutgers.edu (robert Steuer)
Newsgroups: sci.electronics
Subject: Need Spice MODEL for 2N5179
Date: 6 Nov 92 04:24:31 GMT
Organization: Rutgers Univ., New Brunswick, N.J.

The title says it all, if you could help I would be very thankful!
-------------------------------------------------------------------------------
| Robert Steuer               Internet: steuer@clam.rutgers.edu               |
| Rutgers University          Amateur Radio: KF2EK@N3FOA.#EPA.PA.USA.NA       |
-------------------------------------------------------------------------------
From: joeld@hpnmdla.sr.hp.com (Joel Dunsmore)
Date: Wed, 11 Nov 1992 06:54:22 GMT
Subject: Re: antennas and grid dip ocillators
Organization: Hewlett-Packard, Santa Rosa, CA
Newsgroups: sci.electronics

Its been several years since I used a GDO (Heathkit, at that), but
I think that they work best to test high Q resonators.  Many antennas
are intentionally low Q (broad band), and it is difficult to couple
enough energy into them to see a distinct dip.  

     My recollection is that a GDO indicates by having energy coupled
out of the coil on top, into the circuit under test.  If this coupling
is too stong, no dip or rather, a big continuous dip.  If the coupling is
weak, or the Q of the test circuit is low, small dip.

Joeld

Newsgroups: sci.electronics
From: cab@col.hp.com (Chris Best)
Subject: Re: Radio Transmitter
Date: Fri, 6 Nov 1992 18:36:03 GMT
Organization: your service

> I need to make a simple radio frequency transmitter with the following
> characteristics: range of a few miles, transmit on a single frequency, 
> energy derived from a button cell, CHEAP.

----------

You're trying to make a commercial killer, aren't you?
From: whit@carson.u.washington.edu (John Whitmore)
Newsgroups: sci.electronics
Subject: Re: Op amp configuration question
Date: 6 Nov 92 04:20:48 GMT
Article-I.D.: u.1992Nov6.042048.7159
Organization: University of Washington, Seattle

In article <1992Nov5.012546.17925@doug.cae.wisc.edu> kolstad@cae.wisc.edu (Joel Kolstad) writes:
>Hi Mike,
>
>In article <1992Nov05.043724.130701@zeus.calpoly.edu> mruddick@joule.elee.calpoly.edu (Michael Ruddick) writes:
>>Be careful...you should only have to use one op-amp for what you are doing.
>>It sounds like you want the op-amp to amplify your signal as much as
>>it can, then pass it to another one that does the same thing.  Op-amps
>>don't work like that...

>However, I did want to point out that there's a very good reason (in general)
>for using two cascaded op amps (providing *x*y gain=*xy gain) rather than
>using just one (providing *xy) -- the gain bandwidth product.  You can
>show mathematically, in not too long of a time, that the closed loop
>gain bandwidth product of two cascaded op amps is greater than that of
>a single one for the same gain conditions.

	That's true, BUT one is not cascading OP AMPS in this case,
rather one is cascading limited-gain amplifiers.  You have to close
TWO feedback loops on two cascaded op amps, or the frequency
compensation becomes very difficult.  Two cascaded limited-gain
amplifiers is a very common configuration: the first is called
the 'preamplifier', and is selected for input impedance and 
low noise.  The second amplifier (power amp) would have requirements for
driving the load, for dynamic range, etc.

	Because the two amplifiers have different requirements,
it is more common to find a single-transistor preamp and op amp
output stage, or op amp input stage and power transistor output buffer.

	John Whitmore
From: vwass@sdcc13.ucsd.edu (Vincent Wass)
Newsgroups: sci.electronics
Subject: Disk drive fails when pc card plugged, why?
Date: 8 Nov 92 11:08:45 GMT
Distribution: usa
Organization: University of California, San Diego

I am having trouble with a computer interface project.  I'm trying
to decode addresses on the bus for my own plug-in wire-wrap card.
So I used a 74ls688 compare chip to
decode address lines A2 to A9, and then I wired A0 and A1 to an 8255
chip.  I've wired the address to be 300hex.  I've also tried 280hex,
but I had the same problem.

My only problem seems to be that while the card is plugged
in, both of my disk drives (5 1/4, and 3 1/2) have some sort of
problem copying files to my hard drive.  When I type chkdsk at the
drive prompt, the error message 
<filename> 
 Is cross linked on allocation unit 129
etc...
And in general, I can copy only a small amount of what is stored on
the disk, and I usually get an error :sector not found on disks that
I know are good.  I'm stuck.  Any help would be very appreciated.  Thanks. 


Newsgroups: sci.electronics
From: jeffs@austlcm.sps.mot.com (jeff stump)
Subject: Radar Detectors
Organization: Motorola Inc, Austin, Texas
Distribution: usa
Date: Thu, 12 Nov 1992 18:00:23 GMT


  I am in the market for a radar detector. Any reccomendations ?
***********************************************************
**  Jeff Stump                                           **
**  Motorola Inc, Austin, Texas                          **
**  E-mail:  jeffs@austlcm.sps.mot.com                   **
***********************************************************




--
***********************************************************
**  Jeff Stump                                           **
**  Motorola Inc, Austin, Texas                          **
**  E-mail:  jeffs@austlcm.sps.mot.com                   **
From: gk@dcs.ed.ac.uk (Gavin Kerr)
Newsgroups: sci.electronics
Subject: WANTED - LIST OF SCART PINOUTS
Date: 10 Nov 92 12:21:09 GMT
Organization: Department of Computer Science, Edinburgh University

Does anyone have a complete list of the pinouts for a scart/peritel plug.
I have them at home, but I need to make up a lead this week, and I cant get 
back until the weekend.

I would appreciate it if you could email me or post them to the net, whichever.

Please just get them to me in whatever way you can, I *NEED* them ASAP...


					Thanx in advance,
							Gavin Kerr


email: gk@dcs.ed.ac.uk

*******************************************************************************
* Life, dont talk to me about life            *    GGGG        A   V       V  *
* Why stop now, just when Im hating it?       *   G           A A   V     V   *
* Ford, Your turning into a penguin, stop it! *   G   GGG    A   A   V   V    *
* Yes, as you say, in the mud                 *   G     G   AAAAAAA   V V     *
* From the hitch hikers guide by D. Adams     *    GGGGG   A       A   V      *
*******************************************************************************
From: agodwin@acorn.co.uk (Adrian Godwin)
Newsgroups: sci.electronics
Subject: Re: Autodialer
Date: 6 Nov 92 17:55:18 GMT
Organization: Acorn Computers Ltd, Cambridge, UK

In article <1992Nov6.010038.3104@msdrl.com> karkan@msdrl.com (Jim Karkanias) writes:
.. Does anyone know of a public domain or shareware program that would let me
.. assemble an arbitrary string of characters (representing those keys on a
.. telephone) and send them to a modem?  I'd like to be able to programatically
.. control a remote process; this process uses the phone as an interface...
..
.. Any info is much appreciated.  Thanks.
..
.. Jim

I would have thought that any popular commms program (Telix, Procomm, etc if you're
using MS-DOS on a PC-clone) would do this as part of the autodialer support.
In fact, a simple terminal emulator would do if you don't mind retyping the
sequence every time you want it : the DTMF dialer in a modern modem will do all
the hard work.

-adrian


-- 
Adrian Godwin : agodwin@acorn.co.uk : adrian@fangorn.demon.co.uk : g7hwn@gb7khw
ObDisclaimer  : I believe this rubbish .. don't imagine that anyone else does.
Newsgroups: sci.electronics
Subject: HC11 RTI
From: <DI3QC@CUNYVM.BITNET>
Date: Thursday, 12 Nov 1992 01:14:25 EST
Organization: City University of New York/ University Computer Center

     I am having problems setting up a real time interrupt. I would like the
interrupt that signals every 20ms or so. I am first setting RTII bit in TMSK2
register $1024. This I think enables the RTI interrupt. Then I am setting the
RTI vector $fff0 with the address of my routine. The first part of my routine
clears RTIF bit in TFLG2 $1025. Then I have my routine with it ending RTI. All
my interrupt routine does is count ten of these RTI and then sets a port where
I have an led connected. Then it turns the led off and resets count (a memory)
location to 0. This way I have a delay. My problem is while in PC BUG I get
locked out and the led doesnt light. I know I am not overwriting the PCBUG
talker and the led routine works fine. My problem is with the RTI. Any
suggestions would be great. Also does anyone have any suggestions to a lab
type manual with experiments to be conducted with an HC11. Well thanks.



                                                         Alex Jeannopoulos
From: f92anha@fy.chalmers.se (Anders Hammarqvist)
Newsgroups: sci.electronics
Subject: Re: Autodialer
Summary: modem dialing
Keywords: modem
Date: 8 Nov 92 14:23:14 GMT
Organization: Chalmers University of Technology

In article <1992Nov6.160857.16550@unislc.uucp>
mgc@unislc.uucp (Marc Christensen) writes:
>Jim Karkanias (karkan@msdrl.com) wrote:
>: Does anyone know of a public domain or shareware program that would let me
>: assemble an arbitrary string of characters (representing those keys on a
>: telephone) and send them to a modem?  I'd like to be able to programatically
>: control a remote process; this process uses the phone as an interface...
>: 
>The problemI ran into and you probably will to was ...
>the modems all expect a dial-tone before they will dial. No tone No Dial.
>If the device "Answers" the phone then you will need to find a way around it.
>Do the regular/Leased line switches on a modem disable this feature?

On most modems sending ATX3 will disable dialtone checking.

>Making the modem dial is simple you need to send ATDT1234567890*# out the
>serial port for a standard hayes modem. some brands will also handle A,B,C,D
>codes like in a 12 digit pad.

Also, adding a ; at the end of the ATDT123 will put the modem back into
command mode so that you can send another ATDT123 sequence without having
to hang up.

Anders Hammarquist
From: ah335@cleveland.Freenet.Edu (Richard Banks)
Newsgroups: sci.electronics
Subject: calculating bandwidth for op amps
Date: 13 Nov 1992 17:35:33 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 need some general formulas for calculating the overall signal
bandwidth of chained op amps.

The only formula I have now is:

'f_A = f_t/(1 + R_2/R_1)

Where f_t= a_0(f_a)

a_0 = dc gain
f_a = frequency repsonse of the open-loop response

And R_2 and R_1 are the resistors of the standard nonverting op amp
configuration.

Does anyone have anything simpler than this?
Thanks.
Newsgroups: sci.electronics
From: markr@austlcm.sps.mot.com (mark rossman/xcn70)
Subject: WANTED: Sources for tube amp parts.
Organization: Motorola Inc, Austin, Texas
Distribution: usa
Date: Thu, 5 Nov 1992 16:52:51 GMT

I am in the process of designing a tube pre-amp for a guitar amplifier and
am looking for sources for parts.  I am looking for power transformers, tubes,
sockets, etc.

If you know of any mail-order shops that carry these items please email me.

Thanks,
markr@austlcm.sps.mot.com
From: cstadbg@csv.warwick.ac.uk (Mr M J Brown)
Newsgroups: sci.electronics
Subject: doherty@melpar R DETECTOR TUBE WANTED
Date: 6 Nov 1992 13:22:45 -0000
Organization: Computing Services, University of Warwick, UK
Expires: 30 Dec 92
NNTP-Posting-Host: clover.csv.warwick.ac.uk

----------------------------------------------------------------------------

To: doherty@melpar
Subject: Re: IR detector tube wanted
Newsgroups: sci.electronics
Organization: Computing Services, University of Warwick, UK

That price sounds a bit steep...I did hear mention of around 99 dollars
for a 6032 type tube... maybe there are two types of tube, what I want
is just the glass tube bit....I can make up case/EHT psu etc. myself.

=============================================================================  
     _/      _/   _/   _/  _/   _/_/_/_/   |
    _/_/  _/_/   _/   _/_/     _/          |         Michael Brown
   _/  _/  _/   _/   _/       _/_/         |
  _/      _/   _/   _/_/     _/            |   cstadbg@csv.warwick.ac.uk
 _/      _/   _/   _/  _/   _/_/_/_/  _/   |
=============================================================================

I could not send this message via mail to doherty@melpar .... It got bounced!
From: FELSON_ADJ@CCSUA.CTSTATEU.EDU
Newsgroups: sci.electronics
Subject: Software for touchtone generation; will it work?
Date: 10 Nov 1992 11:47:54 -0600
Organization: UTexas Mail-to-News Gateway
NNTP-Posting-Host: cs.utexas.edu

Can a squarewave output be used to reliable generate
touch tones?  I'm planning on writing some machine code
software for an HP48 calculator that would do the following:
  scan two sine wave tables ( or use two pointers into a single table )
  add the two together, and turn the speaker on whenever the sine
  is positive.  

This would be basically a cliped version of the dual done MTMF signal.
Anyone know if this will be too distorted for the phone company to accept?
From: ninke@cactus.org (Don A. Ninke)
Newsgroups: sci.electronics
Subject: FOR SALE: 74F676 chips
Date: 6 Nov 92 14:22:20 GMT
Article-I.D.: cactus.1992Nov6.142220.19884
Distribution: usa
Organization: Capital Area Central Texas UNIX Society, Austin, Tx

FOR SALE:      10 each  Fairchild 74F676PC chips
               (16-bit Serial/Parallel In, Serial Out Shift Register)
               FAST Advanced Schottky TTL

       Asking $25.00 for the bunch (and I'll pay the postage)
-- 
--------------------------------------------------------------------------
Donald Ninke, 2307 Lehigh Drive, Austin, TX 78723-2113       ninke@cactus.org
Newsgroups: sci.electronics
From: mgc@unislc.uucp (Marc Christensen)
Subject: Re: 386 replacement chip
X-Newsreader: TIN [version 1.1 PL6]
Organization: Unisys Corporation SLC
Date: Thu, 5 Nov 1992 16:26:51 GMT

Christian Ricci (newsman@stein.u.washington.edu) wrote:
: I just saw an ad for an Intel built 80386 replacement chip called the 
: RapidCAD Engineering CoProcessor.  It is supposed to give up to 70% improve-
: ment for technical applications.  It comes with two chips.  One replaces 
: the 80386 and one goes in the 80387 slot.  Any idea what this thing is and
: how it speeds up the computer?
: 
The 80387 speeds up Floating Point OPs and selling you a
new 80386 increases intel Profits ??


Seriously I don't know I havent heard about it yet.
It sounds more like marketing than Technology to me.
The '386 may be optimized for Math operations.

Marc Christensen 
What is the Half life of Pentium?

Newsgroups: sci.electronics
From: medin@catbyte.NoSubdomain.NoDomain (Dave Medin)
Subject: Re: 12 V -> 3V, 0.6 A
Reply-To: medin@catbyte.b30.ingr.com
Organization: Intergraph Corporation, Huntsville AL
Date: Mon, 9 Nov 1992 23:16:17 GMT

In article <sehari.721280522@class1.iastate.edu>, sehari@iastate.edu (Babak Sehari) writes:
|> In <1992Nov7.141550.538@ludd.luth.se> d89-ahg@ludd.luth.se (Anders Hedberg) writes:
|> 
|> >A friend wants to listen to his CD player powered from the car.

|> There are many ways to do this the cheapest way is to put:
|> 
|>   12-3
|> --------- = 13 diodes in series with the input voltage of your CD player,
|>     0.7
|> 
|> Like this:
|> 
|> +12V -|>|-|>|-|>|-|>|-|>|-|>|-|>|-|>|-|>|-|>|-|>|-|>|- +3V
|> GRD  --------------------------------------------------
|> 
|> The problem might be generated if the input voltage swings.  To avoid
|> this problem try putting a 2N3055 transistor as follows:
|> 
|> +12V |>|-|>|-|>|-|>|-|>|-|>|-|>|-|>|-|>|-    ---+3V
|>                                         | \_/ Emitter
|>                                         R  |
|>                                         |--|
|>                                         |
|>                                         ||>|-|>|-|>|-|>|-|>|-|
|>                                                              |
|> GRD ---------------------------------------------------------+-----

Best to avoid the first solution. First, diode drops are
only approximately 0.6 volts (they vary in *practice* from about 0.5
to 0.7 volts at room temperature). The drop varies with temperature.
The voltage drop is also sensitive to bulk resistance of the
junction among other things, and is thus hard to predict. The
"regulation" (impedance of the supply) will be much worse than
a battery. So even if the source voltage does not swing, this circuit
is a nix.

The second circuit also has shortcomings, although less so as the
diode voltage uncertainties only show up from the transistor's base
to ground (fewer diodes). The only purpose for the diodes on the
transistor's collector would be to dissipate a majority of the power
(something a properly heatsinked 3055 is MUCH better at doing than
small power diodes). There is no reasonable voltage compliance
available at the collector, as shown, either. You could remove some
or ALL of the collector diodes, choose R to give a current through
R of 1/20 the load current, and go with it. But then, you've
exceeded the cost and simplicity of a simple LM317 regulator
as shown by another poster.

You'd be much better off with a regulator like the 317 as
suggested. It is simpler, inexpensive (costs less than a 3055
transistor), and provides regulation as a side benefit.

-- 
--------------------------------------------------------------------
       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: chaplin@keinstr.uucp (Roger Chaplin)
Subject: Re: Teeny-weeny Sony power connector?
Organization: Keithley Instruments, Cleveland, Ohio
X-Newsreader: TIN [version 1.1 PL6]
Distribution: usa
Date: Fri, 13 Nov 1992 14:30:03 GMT

Michael Schuster (schuster@panix.com) wrote:
[ concerning Bradley G. Kaiser's need for a special Sony power connector ]
: I ran into the rame problem with my ICF-SW55 when looking for a car power
: adaptor. Sony has you by the "Balls". The new "Unified" power connector
: has not yet been cloned.

The problem with different power connectors did not just suddenly
appear when Sony came out with their "Unified" power connector.  There
were already a few different sizes of the coaxial power connector in
use.  I found this out the hard way when I purchased a CD-to-FM-radio
adaptor for my car.  It supplies power to whatever portable stereo you
want to connect via a cable with a `standard' power connector at each
end.  The trouble is, the supplied connector ALMOST fits each of my
portable stereos (except the new Sony CD player).

My solution was to fit a truly standard connector in-line in the AC
adaptor for each of the portable stereos, and also put the same
standard connector on the end of the power cord coming from the
CD-to-FM adaptor.  The connector I chose was a 3-conductor (stereo)
1/8" phone jack/plug.


  ------------
  |          |
  |   AC     |                     ______         _____             _______
  | Adaptor  |---------------------|    |       --|   |-------------|     |
  |          |                     ------         -----             -------
  |          |                      1/8"           1/8"             original
  ------------                     stereo         stereo           AC Adaptor
                                   in-line         plug               plug
                                    jack


When I want to use the portable stereo in the car, I take it AND the
`pigtail' adaptor cord, and plug it into the 1/8" jack on the end of
the car adaptor's power cord.

The reason I chose a 3-conductor (stereo) rather than a 2-conductor
(mono) connector is that for some stereos, the `ring' of the connector,
rather than the `tip', is the positive voltage connection.  All of the
2-conductor plugs I've seen have exposed metal which is connected to
the ring.  I didn't want any chance of shorting that conductor to the
grounded metal of the car's gear shift, etc.

-- 
Roger Chaplin / Instruments Division Engineering / "This land is your land,
chaplin@keinstr.uucp / CI$: 76307,3506          / This land is my land,
#include <disclaimer.h>                        / One of us has a bogus deed
#include "disclaimer.h" /* cover all bases */ / to this land."  - George Carlin