HDTenEightyP/NetNews huggingface dataset:
From: petry@vxcrna.cern.ch (PETRY,DIRK./PPE)
Subject: making mono from stereo
News-Software: VAX/VMS VNEWS 1.41    
Organization: European Organization for Nuclear Research, CERN
Date: Tue, 10 Nov 1992 16:40:00 GMT

How can the two speaker outputs of a stereo hifi set be combined to one?

Since the human ear is only able to locate sources of sound if they
emit medium or high frequencies, it is not sensible to have two bass
speakers in a hifi set. A cheaper but as good solution would be to
have two medium and high frequency speakers, and only one bass speaker
connected to both output channels.
Surprisingly there no solution to this available, not even at  
specialized hifi electronics shops.
Newsgroups: sci.electronics
Subject: Wanted: Info on Altair 8800b
From: kmwheeler@ualr.edu
Date: 11 Nov 92 18:28:05 GMT
Organization: University of Arkansas at Little Rock

I am the owner of my uncle's old MITS Altair.
(1978 model 8800b).  I have some software (CP/M),
two complete 8" drives, the computer and a terminal.

It would occasionaly run when I got it.  Now it is rather
dead.  I'd like to get it up and going to use it for 
experimentation (it's got a lot of slots for expansion
cards).  I have practically no documentation.

I am interested in info (old magazine articles, books) on
this beast.  I really need to find some good in depth
technical info- schematics, bus specs, programs, etc.

I may be interested in buying any old Altair parts.

Keith Wheeler
University of Arkansas at Little Rock
senior, Computer Engineering Technology

"We choose to do these things not because they are easy,
 but because they are hard" - JFK's moon speech
From: ac94691@dunix.drake.edu (The Dark Kitty)
Newsgroups: sci.electronics
Subject: Re: Big Brother Radio Shack
Date: 13 Nov 92 19:06:10 GMT
Organization: Drake University, Des Moines, Iowa, USA

In article <1992Nov10.112934.60615@cc.usu.edu> slmdj@cc.usu.edu writes:
>BTW... What really _ticks_ me off is the way the RS zombies often jack me 
>around as a customer.  Example:  Since I am only 18, this happened just a 
>couple of years ago...  I was back in their parts section, looking for some 
>capacitor or other.  Lo, and behold, one of their salesmen walks up to me and
>tells me to get out of there, that there couldn't _possibly_ be anything back
>there that *I* could ever want!!!  I tried to reason with the guy, but he was
>a little lacking in the logic portion of the brain...:-)  Same when I spoke 
>with the manager!

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!

I, too, in my teens had a problem with the salesman treating me like a
punk.  BTW in my town the only competition to Radio Schmuck is a
wholesale parts store owned by an old fart who doesn't seem to realize
that we've invented digital parts yet.  He's actually priced worse than
RS.  They're general response to a walk-in/non-business customer is to
treat you like dirt and ignore you if possible.  One day I really ticked
off a salesperson.  He was standing talking to a really ugly, scraggy
looking guy who was obviously a pal:

Salesdoof: Yeah Bob my old lady's really gettin me down...
Me:  Um...could you help me out with some...
Salesdork: I'll be with you in a minute.
Salesdroid: So anyway I told her if she wanted me to work on the car
less, maybe she could give up her job and make some time for ME.
Me:  [after waiting like 5 minutes]  Listen, I just need you to look up
a part in the catalog.
Sales-spud:  I'm with another customer at the moment.  I'll be right
with you.
Me:  [getting ticked cause the guy he's talking to is clearly not
involved in a business discussion]  Whatever...

So I walked around the counter, right up to the catalog, and started
looking through it for what I needed.  He got irate and started yelling
about how I shouldn't be back there, get out of store, etc.  I told him
if he was gonna chat with his pal, then I'd have to get what I needed 
myself.  Of course, that's when I mentioned that my sister was the
office manager, a position of much higher rank than his own.  =-)

Boy, he got real helpful then!!!

So I tend to shop at Radio Schlock even when I don't want to because
at least there you don't have to deal so much with smelly guys talking
about being neanderthallic in their personal relationships.  =-)

Anthony Clifton
From: cstadbg@csv.warwick.ac.uk (Mr M J Brown)
Newsgroups: sci.electronics,comp.robotics
Subject: sdmw91tw@ap08.rz.tu-harburg.de
Date: 6 Nov 1992 13:25:39 -0000
Organization: Computing Services, University of Warwick, UK
Expires: 30 Dec 92
NNTP-Posting-Host: clover.csv.warwick.ac.uk

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Subject: Returned mail: Host unknown

   ----- Transcript of session follows -----
550 ap08.rz.tu-harburg.de (ether)... 550 Host unknown
554 sdmw91tw@ap08.rz.tu-harburg.de... 550 Host unknown (Authoritative answer from name server)

   ----- Unsent message follows -----
Date: Fri, 6 Nov 1992 10:41:17 GMT
From: Mr M J Brown <cstadbg@csv.warwick.ac.uk>
Received: by clover.csv.warwick.ac.uk
	id AA19945; Fri, 6 Nov 1992 10:41:17 GMT
To: sdmw91tw@ap08.rz.tu-harburg.de
Subject: Re: Eproms
Newsgroups: sci.electronics
Organization: Computing Services, University of Warwick, UK

In article <2023@rztsun.rz.tu-harburg.de> you write:
>
>I have a little problem with megabit-EPROMs:
>
>Are there any differences between 27c010-120 and 27c020-150 other than:
>
>I was trying to replace the 1Mbit Eproms with 2Mbit, but the system does not
>recognize the chips at all. At least, when I am trying to read from the 
>2Mbit Eprom the system acts as if there was no chip at all.
>

>What is the problem?
>
>

The problem could be that the extra address line that the 2 Meg eprom has
is not connected anywhere in the device you are plugging it into, or it is
tied off to the wrong voltage rail. If your Programmer programs the lower
half of the chip (High Address line = Logic 0 ) and that pin is tied to
+5v (Logic 1) in the application circuit, then you have exactly what you
describe .... the circuit is trying to run with a blank eprom in it!

You could modify the equipment so that the highest address line is tied to
0v ... but make sure you get it right!

=============================================================================  
     _/      _/   _/   _/  _/   _/_/_/_/   |
    _/_/  _/_/   _/   _/_/     _/          |         Michael Brown
   _/  _/  _/   _/   _/       _/_/         |
  _/      _/   _/   _/_/     _/            |   cstadbg@csv.warwick.ac.uk
 _/      _/   _/   _/  _/   _/_/_/_/  _/   |
=============================================================================
From: U40348@uicvm.uic.edu (Jay Lorenzana)
Newsgroups: sci.electronics
Subject: Motorola S19 ==> S2 record. How?
Date: 10 Nov 92 05:26:50 GMT
Article-I.D.: uicvm.92314.232650U40348
Organization: University of Illinois at Chicago

Our school is ill-equipped.  We have an old eprom burners
that will only program Motorola S1 and S2 record files.  How
can I convert my S19 record file to S1 and S2?

Are there any complications in modifying hex files?

And what is a hex to obj file converter?

Thanks for any help you can give,
                                  Jay

A piece of my s19 rec:

S123C00000000000000000BDC048BDC09ABDC063BDC0A5BDC0BA7FC0037DC0002605BDC0E0
S123C020CE20F30F7DC002261A1A8300FF2B02200DCE10001F2E40FC962ED72F20D5BDC2F2
S123C0408120D0BDC28B20CBCE10008EDFFF862F97EECCD000DDEFC60CE73F86100686016F
......
lines deleted
......
S123C3E02A2A204552524F52202A2A202020202020202020202020202020202055702020A2
S121C40020202020202020202020446F776E204A4F59535449434B204D4F444520202D
S123D0008600BDC285FEC001140301BDC156432607BDC110BDC0BA3B432607BDC237BDC0C4
S123D020BA3B432607BDC1CFBDC0BA3B4326158C000026013BBDC1D01400017DC00427038E
S121D040BDC0BA3B8C00002603BDC110BDC0FDBDC14F8C00112706BDC0BABDC3313BE5
S9030000FC


         Univeristy of Illinois
               at Chicago

                                   Internet: U40348@uicvm.uic.edu
                                   Bitnet  : U40348@uicvm.bitnet
Newsgroups: sci.electronics
From: heyes@dadev.cebaf.gov (Graham Heyes)
Subject: WANTED: 16-20MHz 68020 or 68030
Organization: Continuous Electron Beam Accelerator Facility
Distribution: sci.electronics
Date: Wed, 4 Nov 1992 21:44:17 GMT

I am looking for either a 68020 or 68030 to play about with
in a "breadboard" project. The circuit I already have has
a 16MHz 68000. I had a look at the cost of new chips in a
catalogue and almost gave up on the idea there and then.

	I was wondering if anyone reading this has a 16-20
MHz 020 or 030 which they have either from scrap equipment
or left over when upgrading to a chip with a higher clock
speed. If you have then drop me an E-mail with a price.

	Thanks
		Graham Heyes.
Newsgroups: sci.electronics
From: billq@ms.uky.edu (Billy Quinn)
Subject: Re: making mono from stereo
Date: Wed, 11 Nov 1992 17:46:58 GMT
Organization: University Of Kentucky, Dept. of Math Sciences

petry@vxcrna.cern.ch (PETRY,DIRK./PPE) writes:

>How can the two speaker outputs of a stereo hifi set be combined to one?

>Since the human ear is only able to locate sources of sound if they
>emit medium or high frequencies, it is not sensible to have two bass
>speakers in a hifi set. A cheaper but as good solution would be to
>have two medium and high frequency speakers, and only one bass speaker
>connected to both output channels.
>Surprisingly there no solution to this available, not even at  
>specialized hifi electronics shops.

Well, assuming the low frequencies from both channels are crossed over
(filtered out of the signal) before you hit the power amp of your stereo
system, then you could just tie them together.  Then send that one signal 
to a bass power amp and then to your 'bass speaker'.

But I have to wonder what all of those Beatles albums will sound like.
Alot of them have the bass only in one of the two speakers - and I like
it that way.



-- 
*-----------------------------------------------------------------------*
*	Bill Quinn			billq@ms.uky.edu		*
*-----------------------------------------------------------------------*
Newsgroups: sci.electronics
Subject: Re: microcontrollers
From: govindg@ucunix.san.uc.edu (Girish Govind)
Date: Thu, 12 Nov 1992 22:01:12 GMT
Organization: University of Cincinnati
Keywords: sizes? Exrternal Memory Capability

In article <1992Nov12.180027.5230@bnr.ca> mwandel@bnr.ca (Markus Wandel) writes:
>In article <1992Nov12.023508.13285@tamsun.tamu.edu> rahhelp@rigel.tamu.edu (Ronald A. Huizar) writes:
>>
>>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.
>

Why not do some compression while you are getting the data? You can try one of
the data bandwidth reduction methods -- delta modulation etc should 
be pretty easy to do. I guess obtaining a model for short-term data may also
be possible (this is just a thought) computing the reflection coefficients etc
is pretty optimized now.

I have a "Phone-Mate" answering machine that does digital recording of
messages. It takes messages of total length about 35minutes. And this thing
costed me about 130 bucks. So, if you can compute the amount of memory (10MB!)
you will know that they are not just saving the message samples directly! The
reconstructed speech is a little rusty but it's alright. 

There is a TI Voice-Band Audio Processor that seems like a pretty good thing
to use for a project like this. It has stuff for preprocessing and
postprocessing (amplification) etc. built onto it.

This is just off the top of my head. My $0.02.

-- Girish Govind

Newsgroups: sci.electronics
From: gan@sample-o.eng.ohio-state.edu (Yin Huang Gan)
Subject: Need 800 number for Future Electronics.
Organization: The Ohio State University Dept of Electrical Engineering
Date: Sat, 7 Nov 1992 18:05:25 GMT


Does anyone know the 800 number of "Future Electronics" ?
Please e-mail me about this info to gan@ee.eng.ohio-state.edu. 

Actually a friend of mine needs 68hc05kics (I got no idea what this is) 
which was available at "Future Electronics" but if you know other places, 
let me know about it as well.

Thanks a lot.
-- 


Newsgroups: sci.electronics
From: siegel@cae.wisc.EDU (Jeffrey Siegel)
Subject: Cause of failure in keypads?
Organization: Who has any organization?
Distribution: usa
Date: 11 Nov 92 19:53:57 CST
Originator: siegel@hp-11.cae.wisc.edu
Keywords: failure


I have a cordless phone on which the buttons no longer
work reliably. I took the phone apart and disassembled
the keypad unit. It is a typical key mechanism: Some
sort of rubbery-black-plastic which I assume is
conductive presses against a spiral circuit board trace
to cause a button-press event. The circuit board traces
were dirty, so I cleaned them with rubbing alcohol and
figured that would be the end of the problem.
Unfortunately it wasn't. So I cleaned it again and 
rearranged the buttons (Only the '1' button doesn't work)
with no change. When you press the '1' button, the key
bounces and produces several '1's, obviously no good for
dialing the phone :-(   So if the circuit traces are
clean and the plastic button works for other numbers
on the keypad, what is the problem? 

Jeff
From: aaron@barracuda.micro.umn.edu (Aaron C. Sawdey)
Newsgroups: sci.electronics
Subject: Re: Question on BeO , Be Cu
Date: 8 Nov 92 18:14:13 GMT
Article-I.D.: news2.1992Nov8.181413.6384
Organization: University of Minnesota, Minneapolis: Under Grad Workstation Lab.

In <40690@sdcc12.ucsd.edu> ikoutsel@sdcc3.ucsd.edu (Ioannis Koutselas) writes:

>Hello. I would like
>to ask if someone kwows the minimum levels of exposure to BeO
>and BeCu dust ?  I have accidentally (kind of) used BeCU
>to make springs for an experiment, without ever knowing that
>the dust of Be is also carcinogenic. Is it that there is
>a minimum exposure level ?

66th ('85-'86) CRC Handbook of Physics and Chemistry says this about Be:

"Exposure to beryllium dust in air should be limited to 2ug/M^3 (8-hr
time-weighted average -- 40-hr week), with a ceiling concentration
of 5ug/M^3. A maximum peak above the acceptable ceiling concentration
for an 8-hr shift is 25ug/M^3 for a maximum duration of 30 min. These
values are being reviewed and studied."

The stuff's pretty toxic, in other words. My first exposure to this was
a lecture about why you should leave immediately if you break the tube
of an Argon-Ion laser (other than the fact that they cost $10k+): the
heated anode in the tube contains beryllium to improve its electron-
emission properties. (We had a tube that didn't work -- we rejuvenated
it by passing a very large (10x normal) current through the anode
heater to drive Be out to the surface of the electrode -- worked great,
we got 5.5W out of an ancient 5W laser (water-cooled)).

>Are the effects of Be chronic ? In other words do Be
>atoms mutilate cells continuously in the human organism
>or is there a decay in the action ? Can our body    
>get rid of Be in some way ?

Hmmm. Any answers to this one? Perhaps a re-post to some more appropriate
group?
From: cyberman@toz.buffalo.ny.us (Cyberman)
Newsgroups: sci.electronics
Subject: Re: 0to24v to -12to+12v c
Date: 11 Nov 92 02:13:43 GMT
Article-I.D.: toz.gate.kPy2TB1w165w
X-Maildoor: WaflineMail 1.00r


   Seaney@engr.wisc.edu was espousing about '0to24v to -12to+12v conve',
   on [11-05-92  20:19] to All!
 Se> I'm in a bind.  The gradstudents before me goofed an purchased a 0 to
 Se> 24 Volt Power Supply (15Amps) to drive a Power OpAmp.  After close
 Se> inspection it became apparent the the OpAMp needs -12to+12V.  Since the
 Se> OpAmp drives a motor we need as much current as possible.

    Uh they didn't goof.  You see +-12v is no different to the
    motor as is 24 volts.  You need to make a virtual ground
    however.  If you don't need reversability there shouldn't be
    a problem.  Another easy solution is 2 0-24v supplies.  Be
    sure the power suppies can SINK current! :)

 Se> Is there a cheap way to convert 0 to 24 Volts (Floating) to -/+ 24
 Se> Volts.  The hard part seems to be the 15 Amp current requirement.

    Ussually is when you get above 10amps.  You could make your
    own :)

        Cyberman
... Life happens between 9am a 5pm for most poeple, no wonder there bored!
--- Blue Wave/QWK v2.10
From: cyberman@toz.buffalo.ny.us (Cyberman)
Newsgroups: sci.electronics
Subject: Re: X-rays, aircraft and
Date: 11 Nov 92 02:15:05 GMT
Article-I.D.: toz.gate.uRy2TB1w165w
X-Maildoor: WaflineMail 1.00r


    Pyrdek@edinboro.edu entitled a message as 'X-rays, aircraft and frie',
   on the 11-06-92  19:48 to All.
 Py> What I am wondering is what is the probability that the x-ray
 Py> unit(s) may have fried the chips or is it more likely that travelling
 Py> in some aircraft hold (possibly unheated and/or unpressurized)
 Py> caused these problems.  Or is it more likely that the various jolts
 Py> and bumps may have caused at least two (and quite possibly more)
 Py> seperate failures at the same time?

 Py> Care to venture an opinion?

    Yes if the micro controller is an OTP and not a MASKED one
    the XRAY devices may have erased some the EPROM bits.  OTP
    micro controller use a non windowed eprom so you can't
    "erase" them.  However you may be able to do it with XRAYS.
    :)

    Cyberman

... In knew it! Life happens just when you think it's over!
--- Blue Wave/QWK v2.10
   
Newsgroups: sci.electronics
From: kolstad@cae.wisc.edu (Joel Kolstad)
Subject: Re: Cable TV Rules
Organization: U of Wisconsin-Madison College of Engineering
Distribution: na
Date: 5 Nov 92 18:23:43 CST

In article <3977@eastman.UUCP> lsls00@iliad.Kodak.COM (Ilia Levi) writes:
>
>Actually you are not buying the whole spectrum of frequencies. Cable company
>is offering you service with certain conditions attached. 

I don't have cable TV here, so I'd have to take a look at my parents to
see just what you sign with the cable company.  Someone I don't think they
word it to the effect that "You are purchasing the reception of 4.5MHz of
this line.  The center frequency of this may be altered at will."

(And heck, even if this were true, in the mathematical sense where you
could instantly change channels you could still sample the entire
spectrum. :-) )

>If you don't like
>those conditions(more money for the extra extensions) you have a right to
>refuse to buy the service. If you CHOOSE to buy their service, you must, morally
>and legally, abide by their rules.

I wholeheartedly agree.

But I think this entire thread is really about just what the cable company
contract meants _legally_.  If a contract says, "You must pay for more than
one hookup," but doesn't specify that I can't receive more than one channel
at a time, then using a distribution amp with that one hook up is a legally
valid way to obtain _more_ hookups.

> If you don't like their rules, get a dish,
>don't watch TV, etc. This is a free country not only for the consumer, but for
>the business as well.

That last sentence doesn't make sense.  Consumers (living, breathing human
beings) live by entirely different rules than businesses (non-sentient
conceptual things), and therefore are "free" in totally different, non-
analogical senses.

As far as getting a dish goes... Be careful!  Pretty soon they may try to
outlaw the reception of your over the air signals!  It's already illegal
to eavesdrop on the celluar phone frequencies, you know.

					---Joel Kolstad
From: paula@nlbbs.UUCP (Paula Stockholm)
Newsgroups: sci.electronics
Subject: Television remote control units (the assasination the
Date: Thu, 12 Nov 92 17:14:02 GMT
Reply-To: paula@nlbbs.UUCP
Distribution: world
Organization: The Electronics Workbench


In article <1992Nov11.140907.21522@thinkage.on.ca> kgdykes@thinkage.on.ca writes:

 > 
 > every couple years or so, the remote will spontaneously die.
 > not battery. not crud build up on sender/receiving units. dead. kaput.
 > 
 > i'm curious, what is the weakness. what dies? is it fairly easy to fix
 > perhaps (replace leds?).
 >
        Gravity, anger, and household pets kill these remotes. Most
        common problem is the ceramic resonator, generally an orange or
        blue or brightly-colored, square-ish component. It's the
        "crystal" that provides clock pulses.

        There is usually a frequency stamped on them. Radio Shack
        carries the common ones. Many other vendors do too. Always look
        the board over for cracks and check that the battery contacts
        are sucurely soldered in place.

        
           Paula Stockholm              paula@nlbbs.UUCP        
          Cumberland, Maine          !nlbbs!paula@uunet.uu.net
Newsgroups: sci.electronics
Subject: Re: Communication on power line
From: Mike_Diack@kcbbs.gen.nz (Mike Diack)
Date: 6 Nov 92 02:52:07 GMT
Organization: Kappa Crucis Unix BBS, Auckland, New Zealand

For those interested in AC modem systems, through bitter experience, 
I'd like to make a couple of suggestions
1 : only top quality X2 rated caps for coupling fron the tank coil to 
the mains.
2 : Beware of the TOKO AO42 style coupling coils - they may be fine 
in 115 volt territory, but ive had one go down with spectacular results
(bright flash out the little window of a 8751 - after which it ceased 
to compute!) with 230 volt systems - a postmortem revealed that the 
enamel on the wire is the ONLY thing that separates primary and secondary.
3 : Remember the fast zener on the driving side of the tank - the resonant 
spikes can get spectacular.
4 : Dont forget the Z-mov.
Other than that, these sorts of units work real well, especially when 
you use micros instead of dumb UARTS, thus gaining error control etc.
From: candy@grumpy.ssc.gov (Candy Robinson)
Newsgroups: sci.electronics
Subject: Need a 74F240
Date: 12 Nov 92 16:14:49 GMT
Article-I.D.: grumpy.CANDY.92Nov12101449
Organization: SSC Laboratory, Dallas, TX

I am having trouble locating a 74F240 surface mount chip for my home
Macintosh. Anyone know where I can get one, or what would be compatible?
Many thanks!

--
Candy Robinson
Superconducting Super Collider Laboratory
2550 Beckleymeade Ave., MS-1002
Dallas, TX 75237
-----------------------------------------
candy@grumpy.ssc.gov
Magnet Test/Data Management Group