HDTenEightyP/NetNews huggingface dataset:
From: slmdj@cc.usu.edu
Newsgroups: sci.electronics
Subject: Re: Big Brother Radio Shack
Date: 10 Nov 92 11:29:33 MDT
Organization: Utah State University

In article <BxBzJK.BqK@news.udel.edu>, bew@brahms.udel.edu (Ben Williams) writes:
> 
> I've just read this thread containing 50+ complaints about Radio Shack.
> What I would like to know is:  Why do we have to shop at RS to get
> electronic supplies?  Why aren't there other electronic stores in
> competition with RS?  Well, maybe there are in your area (let me know)
> but where I live they are the only thing going.  And boy is that ever
> frustrating!  Aren't there laws about monopolies?  Aren't we living under
> a competitive free-market economy where stores that customers do not like
> to go to will be competed with by other stores?  Isn't that the way it's
> supposed to work?  I mean, RS does seem to usually have what I am looking
> for, but I still would like the option at least to do business elsewhere.
> You know, like maybe an electronics store where the salesmen know what
> they are talking about...
> 
> Ben.
> 
> -- 
> Ben Williams
> bew@brahms.udel.edu
> 
>                What we got here is a failure to communicate... 

That's my question exactly!  What I figure the problem is is that there doesn't
seem to be an overwhelmingly great demand for such a business.  Within the 
general public, that is...  A friend of mine tried the electronics parts 
business once, and didn't do so hot.  Sure RS is overpriced (on what they 
*might* just happen to have, but (at least in my town) there aren't too many of
us hobbyists around.  I have found my best (and cheapest) source of parts to be
an electronics teacher I once had who works at the local vocational school...
Being a school, he is able to have a reasonably large inventory, and therefore
buy and sell parts at a good discount.
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!

... Just my $.02 worth!

Paul Cowley
EE Undergrad Extrordinaire
slmdj@cc.usu.edu
From: d1temp@dtek.chalmers.se (Michael Tempsch)
Newsgroups: sci.electronics
Subject: Re: 12 V -> 3V, 0.6 A
Date: 10 Nov 92 06:40:39 GMT
Organization: Chalmers University of Technology, Gothenburg Sweden

schaerer@isi.ethz.ch (Thomas Schaerer) writes:

>Babak Sehari (sehari@iastate.edu) wrote:
>: 
>: 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  --------------------------------------------------

AT 600 mA the voltagedrop over a diod will be more than 0.7V.
I've got one of these in my car (but at 6V out, using 7 diods)
--
|   BTW, all electronic components            |   d1temp@dtek.chalmers.se    |
|   run on smoke. If you let the smoke out,   |   In real life               |
|   they won't work anymore.                  |   Michael Tempsch            |
From: walsh@optilink.UUCP (Mark Walsh)
Newsgroups: sci.electronics
Subject: Re: Radio Transmitter
Date: 9 Nov 92 20:27:13 GMT
Organization: Optilink Corporation, Petaluma, CA

From article <1992Nov06.134655.7132@bnr.ca>, by grier@bnr.ca (Brian Grier):

>> 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.

> I would recommend getting a copy of 73 magazine and look for articles on QRP, 
> less-than 5 watts, transmitters. Remember if you transmit with 0.1watts or 
> more you will need a license.

WHOA!!!  This is the old scoop!  The 'under 100mW' law was
superceded years ago.  Part 97 now has field strength limits
for all ranges of frequencies, and of course, regardless of
power, one cannot interfere with primary users of any band.

Low power communication can indeed be fascinating.  I once
communicated with a friend using only a CMOS crystal clock
oscillator putting out about 8mW into a full sized dipole.

-- 
Mark Walsh (walsh@optilink) -- UUCP: uunet!optilink!walsh
AOL: BigCookie -- Amateur Radio: KM6XU@WX3K -- USCF: L10861
"What, me worry?" - William M. Gaines, 1922-1992
Newsgroups: sci.electronics
From: schuch@phx.mcd.mot.com (John Schuch)
Subject: Cable Channel Modulator?
Organization: Motorola Computer Group, Tempe, Az.
Distribution: usa
Date: Thu, 5 Nov 1992 16:04:04 GMT

Does anyone know where I might find an expensive video modulator
with an output around cable channel 55? I don't really need audio
but it would be nice.

Tnx,
John
From: bk233@cleveland.Freenet.Edu (Jack W. Weinmann)
Newsgroups: sci.electronics
Subject: Re: Needed: 9 pin RS232 specs
Date: 8 Nov 1992 07:08:04 GMT
Organization: Case Western Reserve University, Cleveland, OH (USA)
Reply-To: bk233@cleveland.Freenet.Edu (Jack W. Weinmann)
NNTP-Posting-Host: slc4.ins.cwru.edu


In a previous article, hleaves@gems.vcu.edu () says:

>I'm trying to find out the pin assignments for the standard 9 pin RS232 port
>connector used on many PC's and laptops. I've got the 25 pin assignments, but
>I've had a hard time finding the 9 pin equivalent. If somebody could post or
>mail me the specs I would greatly appreciate it.
>
>Thanks.

Hugh,

I had the same problem.  I had just purchased and Emerson IBM compatible
and couldn't find any information in the manual - so - I called the tech.
support number and here's what they told me:

Serial 9-pin connector for Emerson:

          PIN No.       Function
         ^^^^^^^^^     ^^^^^^^^^^^
            1           Data Carrier Detect
            2           Receive Data
            3           Transmit Data
            4           Data Terminal Ready
            5           Ground
            6           Data Set Ready
            7           Ready To Send
            8           Clear To Send
            9           Ring Indicator

Hope this is correct and helps you out.  I haven't made up my cables yet,
but this is what the tech support group gave me.

Looking forward to see if anyone else has the same pinout.

Jack W. Weinmann  bk233@cleveland.freenet.edu
Newsgroups: sci.electronics
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: PC board manufacture: my technique
Organization: Macquarie University, Sydney
Date: Fri, 6 Nov 1992 00:54:11 GMT


> 	I have made a number of small boards up to 2 by 4.5 inches
> using this process and some with very fine traces and spacings.
> I complete the etching of one side before I apply the toner
> to the other side.   I don't know it this process will scale up to 
> larger sizes well.   It seems to me that the steam step is 
> particularly important.   Before I did this traces would pull off at 
> the edges of the board as the board cooled.
	

This process is unlikely to scale much _because_ of the steam step. The
paper will swell and hence dimensional accuracy will not be maintained.
Our laser printers print accurately onto the paper _before_ it hits the
fuser section. Because of the inherent sizing distortion caused by the
heat cycle in the printer, we need to let the paper (or mylar, more
usually) "rest" for an hour or two before proceeding to the next step.

I've noticed about a 1-2% error in sizing when the paper first comes out
of the printer (this is serious for big components, such as edge
connectors or DIN41612 plugs and sockets). The paper restores its
dimensions as it rests.

JohnH

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

      |  _  |_   _   |_|  _   _|  _|              Electronics Department
    |_| (_) | | | |  | | (_| (_| (_| \/           School of MPCE
    ---------------------------------/-           Macquarie University
                                                  Sydney, AUSTRALIA 2109

    Email: johnh@mpce.mq.edu.au, Ph: +61 2 805 8959, Fax: +61 2 805 8983

----------------------------------------------------------------------------
Newsgroups: sci.electronics
From: ornitz@kodak.kodak.com (Barry Ornitz)
Subject: Re: Radio Transmitter (allowable power levels)
Followup-To: sci.electronics
Summary: Read the FCC Part 15 rules
Organization: Eastman Chemical Company
Distribution: usa
Date: Mon, 9 Nov 92 16:58:11 GMT

In article <1992Nov06.134655.7132@bnr.ca> grier@bnr.ca (Brian Grier) writes:
>Remember if you transmit with 0.1watts or more you will need a license.  

I realize that this statement is correct as written, but it tends to convey 
that no license is needed with transmitter power below 0.1 watt...

When is this nonsense going to be stamped out?  This seems to be a common
urban legend on the net.  There are only three bands where this much power
may be used legally without a license:  the 160-190 kHz band (antenna length
limited to 15 meters), the AM broadcast band - 510 to 1705 kHz (antenna length
limited to 3 meters) and the 49.82 to 49.90 MHz walkie-talkie band (antenna
length limited to 1 meter).  On the FM broadcast band, for example, the
maximum legal power for an unlicensed transmitter is limited to a few
nanowatts!  On many other frequencies, it is far lower.  The FCC Part 15 Rules
and Regulations define what field strengths are permissible when measured at
a fixed distance from the transmitting antenna.  You will usually have to do
antenna near-field calculations to translate these levels back to acceptable
transmitter power once an antenna design is specified.  Remember that the
field strengths are maximum so using high-gain, narrow beamwidth antennas does
not allow you to use higher transmitter power.

The full set of all FCC Rules and Regulations can be found in Title 47 of the
Code of Federal Regulations.  Most good libraries can get this for you.

					Barry
 -----------------
|  ___  ________  |       Dr. Barry L. Ornitz          WA4VZQ
| |  / /        | |       Eastman Kodak Company
| | / /         | |       Eastman Chemical Company Research Laboratories
| |< < K O D A K| |       Process Instrumentation Research Laboratory
| | \ \         | |       P. O. Box 1972, Building 167B
| |__\ \________| |       Kingsport, TN  37662       615/229-4904
|                 |       INTERNET:   ornitz@kodak.com
 -----------------

Newsgroups: sci.electronics
From: cmwolf@mtu.edu (christopher m. wolf)
Subject: Re: UNDERPOWERED HALOGEN LAMPS
Organization: Michigan Technological University
Date: Fri, 6 Nov 1992 19:35:31 GMT

Good lord!  Not this topic again!!!


ARRRRRRRGGGGGGGHHHHHHHH!!!!!!!!!!!!!
From: curt@oasys.dt.navy.mil (Curt Welch)
Newsgroups: sci.electronics
Subject: Re: Adding a Second Phone Line
Date: 5 Nov 92 20:12:46 GMT
Article-I.D.: oasys.27210
Reply-To: curt@oasys.dt.navy.mil (Curt Welch)
Organization: Carderock Division, NSWC, Bethesda, MD

>cathy@uxa.cso.uiuc.edu (Catherine T Vojtas) writes:
>> I need to install a second line so I can have one for voice, one for data
>> (can you guess why?)  The installation charge for the labor of putting in
>> a second phone line is a bit pricey, but the woman at Illinois Bell told
>> me that I could do it myself if I knew how...
>> Anyone know how this is done?

In sci.electronics, rrh@cbnewsk.cb.att.com (richard.w.heebner) writes:
>I think the person you talked with at Illinois Bell misunderstood
>what you wanted. If you want to be able to use voice and data at
>the same time there must be two separate phone lines coming into
>the building.

Richard, I think you misunderstood what the person that wrote the
original aritcle wanted.

>Some money can be saved by doing the
>in-house wiring yourself.

I think this is what he was asking.  i.e., how do you do the in-house
wiring.

The basic concept is simple.  The phone line has two wires.  They will
connect the wires to a block outside the house.  You then have to connect
those two wires to a phone (or modem) inside the house.  How you do this
depends on what type of wire you already have in the house and of course
where you want it.  The tricky part is trying to run the wire if you
don't already have it installed in the walls.  Most new homes these days
have plenty of extra unsed phone lines already strung through the walls.

You can find all the connectors and wire etc at Radio Shack or a hardware
store, or phone store.  You should also be able to find a cheap guide book
at one of these places that will go into lots of details about how to do
the work.  If you have some more specific questions, write me.

Curt
From: whit@carson.u.washington.edu (John Whitmore)
Newsgroups: sci.electronics
Subject: Re: Help: What is an Independent Current Source!?
Date: 9 Nov 92 23:16:39 GMT
Organization: University of Washington, Seattle

In article <Nov.9.00.11.39.1992.9368@clam.rutgers.edu> steuer@clam.rutgers.edu (robert Steuer) writes:
>I understand an Independent Voltage source is like a battery and I
>understand that an Independent Current source can supply a current,
>but what is a REAL-LIFE example of an Independent Current Source?

	A Van de Graaf generator is a good current source; short
of stalling the belt motor or breaking down the insulation between
its electrodes, the output current is not related to the applied
voltage.

	In another sense, a voltage source is only approximately
like a battery; all batteries do have some output resistance
(which, however, may be too small to matter), just as all current
sources have some non-infinite output impedance.  There is
a famous theorem that shows the equivalence of a voltage source
with a series resistance, and a current source with a shunt resistance.
Given that theorem, one can model a real source in either
fashion, with complete confidence.

	John Whitmore
Newsgroups: sci.electronics
From: dannie@coplex.com (Dannie Gregoire)
Subject: Schematics for small audio amp needed...
Organization: Copper Electronics, Inc.
Date: Fri, 6 Nov 1992 17:11:47 GMT
Keywords: audio amp

I am looking for some schematics for a small (ie fit in a 1"x3" emclosure)
audio amp that would boost low level audio up high enough to drive
a pair of head phones.

Any suggestions??  Thanks.

Dannie J. Gregoire
dannie@coplex.com
From: cyberman@toz.buffalo.ny.us (Cyberman)
Newsgroups: sci.electronics
Subject: Re: Schematics for small
Date: 11 Nov 92 02:14:44 GMT
Article-I.D.: toz.gate.0qy2TB1w165w
X-Maildoor: WaflineMail 1.00r


    Dannie Gregoire entitled a message as 'Schematics for small audi',
   on the 11-06-92  17:11 to All.
 DG> I am looking for some schematics for a small (ie fit in a 1"x3"
 DG> emclosure) audio amp that would boost low level audio up high enough to
 DG> drive a pair of head phones.

 DG> Any suggestions??  Thanks.

    Well you could try using an LM301 and a an LM386 in
    conjunction.  The 301 you can hook up to boost say 1-1000 in
    gain and the 386 you can set up for 20.  This will give you
    a range of 20 - 20000 in gain.  That good enough? :)  Now if
    you are talking micro volt levels it's a whole new ball game.

    Stephen
... Look Mom No TAGLINE!
--- Blue Wave/QWK v2.10
                                                                       
Newsgroups: sci.electronics
From: mbattist@magnus.acs.ohio-state.edu (Mark A Battisti)
Subject: HELP: non-intrusive current sensor
Organization: The Ohio State University
Distribution: usa
Date: Thu, 5 Nov 1992 21:46:14 GMT

I need a current sensor (On/OFF) for a standard 110 AC line which
gives a logic signal (5V).  I tried running the live line through a coil
which I ripped out of a small transformer and then amplify the coil
response w/op amps but I could not get this to work.

If anyone has any suggestions they would be much appreciated.

Thank you.

-Mark
mbattist@magnus.cis.ohio-state.edu
From: pcs@cm.deakin.OZ.AU (Peter Smith)
Newsgroups: sci.electronics
Subject: MN3008 BBD REQD.
Date: 12 Nov 1992 06:02:47 GMT
Organization: Deakin University, Geelong, Australia
Distribution: world
NNTP-Posting-Host: aragorn.cm.deakin.oz.au
Keywords: MN3008 BBD REQD.

Does anyone know where I can obtain a Panasonic BBD type MN3008? If you know price and availability and method of payment ie. VISA etc.please include.
    My email address is pcs@.deakin.oz.au
From: ah335@cleveland.Freenet.Edu (Richard Banks)
Newsgroups: sci.electronics
Subject: Re: Television remote control units (the assasination thereof)
Date: 11 Nov 1992 22:04:45 GMT
Organization: Case Western Reserve University, Cleveland, OH (USA)
Reply-To: ah335@cleveland.Freenet.Edu (Richard Banks)
NNTP-Posting-Host: slc4.ins.cwru.edu


In a previous article, kgdykes@thinkage.on.ca (Ken Dykes) says:

>do parts "burn out" in remotes?
>
>every couple years or so, the remote will spontaneously die.
>not battery. not crud build up on sender/receiving units. dead. kaput.
>
>since it's rented from the cable company, i simply take the remote part
>in, and they give me another one.
>
>however, in the last year i picked up an old vcr which uses a Zenith
>remote that looks the same (a few more buttons for vcr controlling :-)
>
>a week ago, BOTH died at the same time. i used both about 10 minutes
>earlier, no problem. i go back to them and neither work.
>
>well, the cable company replaced the converter remote, but i'm stuck
>with a dead vcr Zenith remote.
>i'll probably buy a low cost "universal" with Zenith preprogrammed into
>it. but...
>i'm curious, what is the weakness. what dies? is it fairly easy to fix
>perhaps (replace leds?).
>do spontaneous static discharges from sitting on the couch material or
>carpet floor do them in or something?
>even if i buy a universal, this is starting to bug me. am i somehow
>assasinating the things? i hate mysteries.

We had a month of remote control problems caused by three different
things. 1, the batteries went dead, this really isn't a problem.
2, the cable co. did not give us "remote access" on our cable box.
Here in Cleveland, North Coast Cable charges $1.00 per month extra
for use of a remote control. And 3, the remote signal receiver of
some part of the circuit it is hooked up to went bad and they
came and changed our box.  Yes we really did have all this trouble
with the same remote within a month.
From: jimc@tau-ceti.isc-br.com (Jim Cathey)
Newsgroups: sci.electronics
Subject: Re: microcontrollers
Keywords: sizes? External Memory Capability
Date: 12 Nov 92 18:52:15 GMT
Organization: ISC - Bunker Ramo, Spokane, WA

In article <11NOV199219370593@rigel.tamu.edu> rahhelp@rigel.tamu.edu (Ronald A. Huizar) writes:
>planning to use the MC68HC811E2 can only address about 64K of external 
>...
>about 3 Meg of memeory. To much for the E2. So I know that the 

Ever heard of bank-switching?  Your massive data needs can be easily
handled this way, because you don't need simultaneous access to all
that data.  Your application is specific (and simple) enough that you
can afford to call a subroutine to fetch each sample from RAM that's
not directly in your address space.  No problem.  A similar technique was
used in many external print spoolers, which had 8048's in them.  These
only can directly address something like 2K of memory (my memory's
fading fast), but these used clever bit-banging techniques on DRAMs
connected to I/O ports to store hundreds of K of data.

Engineering Rule #3b:  Work smart, not hard.

-- 
+----------------+
! II      CCCCCC !  Jim Cathey
! II  SSSSCC     !  ISC-Bunker Ramo
! II      CC     !  TAF-C8;  Spokane, WA  99220
! IISSSS  CC     !  UUCP: uunet!isc-br!jimc (jimc@isc-br.isc-br.com)
! II      CCCCCC !  (509) 927-5757
+----------------+
			"PC's --- the junk bonds of the computer industry"
Newsgroups: sci.electronics
From: mgc@unislc.uucp (Marc Christensen)
Subject: Re: Detecting a tone on a phone line
X-Newsreader: TIN [version 1.1 PL6]
Organization: Unisys Corporation SLC
Date: Fri, 6 Nov 1992 16:16:28 GMT

Adam M Gandler (v064mcqs@ubvmsb.cc.buffalo.edu) wrote:
: 
:   I am desining a project that mutes my stereo when the phone rings
: or the receiver is picked up. I want to find a way to remotely
: activate or deactivate this device for when I use my modem. I want to 
: have it so that if I pick up the phone and dial the *, its either
: activates of deactivates. What is the simplest way to detect a touch
: tone signal directly from a phone line. Is it simple as just
: a 567 tone decoder?
: 
there are 2 tones 1 for the column and 1 for the row. so you could use 2
tone decoders or get a DTMF decoder designed for this purpose.
Radio Shack used to sell them. B.G. Micro has them for $2.25 Ea.

Marc Christensen
 
From: gregh@hprnd.rose.hp.com (Greg Holdren)
Date: Wed, 4 Nov 1992 17:36:51 GMT
Subject: Wanted: EPSON MX-100 or MX-80 PCB
Organization: HP Roseville Networks Division
Newsgroups: sci.electronics


 Wanted: EPSON MX-100 printer or the controller PC board for it.
 Its needed to fix a damaged unit. My PC board has to many cracks to
 fix.


 TNX Greg Holdren
 gregh@hornd.rose.hp.com
 (916)771-0659
From: cyberman@toz.buffalo.ny.us (Cyberman)
Newsgroups: sci.electronics
Subject: Re: Heat conduction vs. e
Date: 12 Nov 92 07:33:57 GMT
X-Maildoor: WaflineMail 1.00r


    Matthew W. Hacker entitled a message as 'Heat conduction vs. elect',
   on the 11-10-92  18:02 to All.
 MWH> Are there any substances that conduct electricity well, but
 MWH> conduct heat poorly?  This sort of material would be pretty
 MWH> well suited to thermacouple (Sp?) design...

    Eh most thermocouple applications want heat heat conductivity
    and insulative properties to electricity.  Berelliym oxide is
    a good candidate.  :)

                Stephen Cyberman@Toz.Buffalo.NY.US
             Mangled on Wed  11-11-1992  at 16:24:09

... Hedonism is temporal thinking.
--- Blue Wave/QWK v2.10
                           
Newsgroups: sci.electronics
From: c164-et@po.berkeley.edu (Marco Sebastiani)
Subject: TTL chips and other electronic parts for sale
Organization: University of California, at Berkeley
Date: Mon, 9 Nov 1992 04:19:03 GMT

I have some TTL chips and other assorted electronic parts that I want to
sell, and I'll sell them at the prices listed below or make an offer if you
wish.  Most of the TTL chips are 74LS series (low-power Schottky
transistor-transistor logic). Send inquiries via e-mail to
marcoseb@soda.berkeley.edu or c164-et@po.berkeley.edu (the second account
expires after December 1992, so it might be easier just to send mail to the
first one).

Part Description:		  Price per part,
				 in U.S. dollars:	Quantity:	

single pole double throw switch		1.00		2
smart led's (attach 4 wires, and
	it counts from 0 to 15 in
	hexadecimal: uses 5 volt logic)	3.50		2
2 MHz crystal clock			3.75		1
dip switches				1.25		1
momentary push button switches				2
pre-cut wire jumper kits		11.00		2

chips:

'00					0.20		3
'04					0.20		3
'08					0.20		1
'11					0.20		1
'27					0.20		2
'85					0.45		3
'86					0.20		1
'123					0.45		3
'139					1.00		3
'157					0.40		1
'163					0.45		15
'164					0.45		1
'169					0.60		2
'174					0.40		1
'279					0.35		4
'244					0.55		8
'273					0.55		8
'374					0.55		11
'390					10.00		5
'292				 	1.00		4
2114 RAM chips				1.20		2
555 timer				0.30		1
27C64 EPROM chips			4.00		6
assorted capacitors (mostly .01 and	free with large purchase
	.1 microfarad)
assorted resistors (mostly 330 ohms)	free with large purchase
lots of led's				free with large purchase