HDTenEightyP/NetNews huggingface dataset:
From: sstrong@kean.ucs.mun.ca
Subject: Request for project ideas! Anyone?
Organization: Memorial University. St.John's Nfld, Canada
Date: Thu, 27 Aug 1992 13:44:10 GMT


Good day.

I am an Electrical Engineering student about to enter my last academic term in university.  This
term we can choose all our courses (for specialization) except for one.  This is why I am writing
this letter.

The mandatory course is a project course in which we pick a project and apply what we have
learned for the last five years.  The projects vary in complexity and scope.  Generally there are
two types of projects: a pure research paper in which something new etc. is discussed, and one
in which a prototype of the project is built and tested.  Examples of some projects done before
are neural network theory, design and building of an 8088 stand-alone computer, remote control
using MF and HF frequencies, etc.

My problem is that I can't come up with a project.  Can anyone out there suggest something? 
I am interested in communications, and electronics (no power engineering).  I can program in
C and assembler (80x86).  I am not sure what I want to do, ie. just a report or to come up with
a product and build it.  Note, the projects are usually original and fill some gap in technology. 

Here are some of the things that have crossed my mind:
-Sound processing in real time (ie. effects) (digital or analog).
-Voice synthesis add on card for a single board computer (text to speech)
-Some caller id type of application

I would like to do something with telephone interfacing/computer ... but again, everything I
come up with has either been done before, too simple, too complex.

Any help / ideas received would be greatly appreciated.
Sorry for the long letter.

Steve.
-- 
sstrong@kean.ucs.mun.ca
Electrical Engineering, Memorial University of Newfoundland, Canada
From: sterling@cbmvax.commodore.com (Rick Sterling - Test Eng)
Newsgroups: sci.electronics
Subject: Re: Humidity Sensor Needed (Cheap!!!)
Date: 4 Sep 92 12:34:41 GMT
Reply-To: sterling@cbmvax.commodore.com (Rick Sterling - Test Eng)
Organization: Commodore, West Chester, PA


>>> Can anyone out there help me with my search for something to use as an
>>> electronic relative humidity sensor. So far my search has revealed the> following
>>
>
Sorry for replying to a reply ... don't have the original post.

I built a REALLY cheap humidity sensor many years ago as follows....

Attach 1/4" copper foil to ends of microscope slide and then deposit
a film of carbon black to the assembly with a candle. As I remember, the
device was pretty sensitive. Be sure to clean the slide well and try
to get the carbon black deposited evenly. An op-amp was then used to drive
an A/D converter for a home-brew weather computer.

-- 
 __      __
|__)    (__`
|  \ick ,__)terling
-----------------------------------------------
Test Engineering
Commodore Technology Group  (215)-431-9275
UUCP ...{uunet,allegra,rutgers}!cbmvax!sterling
Newsgroups: sci.electronics,rec.motorcycles
From: datasbld@bnr.ca (Datasbuild)
Subject: Re: Processor recommendations?
Organization: BNR Europe Ltd, Maidenhead, UK
X-Newsreader: Tin 1.1 PL5
Date: Fri, 21 Aug 1992 11:06:29 GMT

Have a look at Intel's or Philip's 80c51.  Philips do a derivative that handles
analogue stuff I believe.  There is the 8096 but I reckon the 8051 should do
for your purposes and there is tons of support for it.

Nick (the Microcontrolled Biker)    DoD 1069    MAG 73516


M'Lud.
From: Rick.Ellis@ofa123.fidonet.org
Newsgroups: sci.electronics
Subject: Re: need encoding scheme for TV remote infrared controller
X-Sender: newtout 0.02 Aug 21 1992
Date: 02 Sep 92  17:39:15

On <Sep 01 17:39> Keith Mancus writes:

 KM>   (1) Is there a standard carrier frequency?  The IR sensor we're using
 KM> detects 40 MHz.

No, but 40 khz is popular.

 KM>   (2) Is the encoding scheme standardized?  If so, what is it?

Nope.
From: massoud@chemteca.sdsu.edu (Massoud Ajami)
Newsgroups: sci.electronics
Subject: Re: coating materials for antennas
Keywords: antennas materials
Date: 31 Aug 92 16:18:02 GMT
Organization: San Diego State University

In article <6790@tekig7.PEN.TEK.COM> thomasn@tekig5.pen.tek.com (Thomas M Nathe) writes:
>From: thomasn@tekig5.pen.tek.com (Thomas M Nathe)
>Subject: Re: coating materials for antennas
>Keywords: antennas materials
>Date: 30 Aug 92 06:22:06 GMT
>I've used hot dip anodizing and zinc oxide paint for aluminum with moderate
>success with the zinc oxide.  The hot dip works well for salt spray and other
>hostile enviroments, don't know the cost though. The zinc oxide paint was used
>as a primer on the helocopters I worked on while doing time in the army.

If for some reason painting is needed for antenna, you should use paint with 
high dielectric constant. The amount of loss based on this process, if you 
drive the boudray condition, is the ratio of both dielectric constants of 
two different mediums. If you have metal with free radical in it as 
sugessted, the field decays (skin depth), and since you can not paint less 
than that thickness, you will lose most of the signal. Most polymers have 
dielectric constant of 2.2 (e.r= Epsilon sub r), remember e.o is 5.8 e-12 F/
m, and e=e.o x e.r.Aluminum oxide has dielectric constant of about 8.0. Use 
ACRYLIC ENAMEL, I believe it has no free radical in it.


Peace and Prosperity!
  ---==< 110 >==---
Newsgroups: sci.electronics
From: strong@tc.fluke.COM (Norm Strong)
Subject: Busy line indicator
Keywords: Good ckt
Organization: John Fluke Mfg. Co., Inc., Everett, WA
Date: Tue, 1 Sep 1992 17:25:24 GMT

Some time ago, there was a request for a circuit that would indicate
that the telephone line was busy.  

I discovered an excellent one in the Dec 91 issue of Wireless World.
If that magazine is not available to you, sending me your US mail
address will secure a copy.  

BTW, it also can turn on a tape recorder!  
-- 

Norm Strong  (strong@tc.fluke.com)
2528 31st S.   Seattle WA 98144   USA
From: bob@comlab.gatech.edu (Bob Baggerman)
Newsgroups: sci.electronics
Subject: Re: Success! Resist Pen Works in HP Plotter!
Keywords: resist pens, pcb, etching
Date: 2 Sep 92 13:30:04 GMT
Organization: Georgia Institute of Technology

Adrian Godwin writes:
>I'd like to go one further than David and avoid the need for chemicals 
>altogether : machining the copper surface directly.

We have one of these machines.  It is essentially a precision XY plotter 
with a motor and a chuck to hold the milling bit.  Its XY accuracy astounds
me.  It is on the order of 0.001".

It works by milling away the copper around the traces you want to keep.  
The trouble is that it is tough to make it work reliably.  The mill bit has
about a 90 degree tip.  To make it cut deep enough the minimum cut width is
about 0.010".  When laying out artwork on 0.025" centers that means line
widths are 0.015".  But the copper clad isn't particularly uniform and 
sometimes the mill bit isn't exactly concentric, both meaning your cut width
ends up being greater.  Pretty soon to get cuts that are deep enough across
the entire board the depth of cut (and hence width of cut) gets great enough
to where there is not much left of your traces.

The machine really is nifty to watch in action.  It would be pretty good for
larger geometry layouts.  I would be hard pressed, though, to recommend 
this style milling machine for PC boards with a lot of DIP IC or any other
dense layout requiring thin traces.  Maybe some other cutting technology
would be the answer but I'm not aware of any currently on the market.

Bob

--
Bob Baggerman                         !  bob.baggerman@gtri.gatech.edu
Communications Laboratory             !  bob@comlab.gatech.edu
Georgia Tech Research Institute       !  qseclrb@prism.gatech.edu
Atlanta, GA  30332  USA               !  404-894-3525
Newsgroups: sci.electronics
From: aduell@nyx.cs.du.edu (Tony Duell)
Subject: Re: Knock Sensor (as in "on a door")
X-Disclaimer: Nyx is a public access Unix system run by the University
	of Denver for the Denver community.  The University has neither
	control over nor responsibility for the opinions of users.
Organization: Nyx, Public Access Unix at U. of Denver Math/CS dept.
Date: Sun, 23 Aug 92 19:40:29 GMT


I've got to reply to this, as I solved the same problem years ago, when I
was at Cambridge University. 
  It was common for students to stick bits of paper on their doors so that
messages could be left. Well, I am a mad hardware hacker, and had to go
one better. I fixed the keyboard off an Atari 400 (membrain type - not
loose biys to get 'borrowed' and a box containing 9 LED's, a DB 25 socket,
and a speaker to the outside of the door. The speaker was connected to a
text-to-speach chipset (SPO256/CTS256 from Tandy), and linked to a spare
RS232 port on my CoCO, running OS-9. The keyboard was encoded by a board
of TTL, and also linked to the port. I created an account called Message,
and you could login there (no password), to leave me messages. Now for the
LED functions. 2 of them gave the shift and control key status, membrain
keyboards beild non-too-reliable. The other 7 gave the system status, and
where I was (In/Out/In the lab/in the terminal room). If you pressed some
special key (break I think), the LED's came on for about 10 second, and a
musical doorbell IC informed me of someone at the door.
  It worked well, but some non-techincal people still had problems, and
resorted to knocking on the door. 

  Now for the solution to the problem - a burglar alarm vibration sensor
switch. These devices are normally closed, and open momentarily if they
are shaken. I used that to trigger a monostable, giving a 10s pulse for
each knock. That also worked the LED's / doorbell
-tony 'PDP11 Hacker' Duell
ard@siva.bris.ac.uk

Newsgroups: sci.electronics
From: sgi@sinope.si.macsch.com ()
Subject: Re: multi-standard VCR`S (Re: NTSC to PAL Did anyone try? )
Organization: The MacNeal-Schwendler Corporation
Date: Wed, 2 Sep 92 20:33:51 GMT

In article <87736@netnews.upenn.edu> sergei@upenn5.hep.upenn.edu (Sergei Borodin) writes:
>In <1992Sep2.103956.14680@lmpsbbs.comm.mot.com> michaelr@ecs.comm.mot.com (Michael Roetzer) writes:
>
>>Where can you buy or mail order multi-standard VCR`s ?  And how much are they?
>>Last year I asked in several electronics and video shops in Tucson, AZ about those VCR`s but they
>>never heard of it.
>
>>     Michael
>
>  I bought mine (Sharp VC780) in Chicago in some Asian region.
>I bet you can do the same in any fairly big city (like LA, NY,
>SF). The bad thing about this multistandard equipment is that
> it's from a  gray market, so don't expect USA warranty. 
>(But so far mine works fine). 
>I paid $392 including tax. (4 head VCR , but nothing "on-screen)
> I've also seen ads in Video Review about multistandard eq.
>
>
>  S.B.



Take a look at the ads in Video Magazine!
There are alot mail-order house selling multi-standard vcrs.

Son Giang
s_giang@mscsch.com




-- 
Son Giang
The MacNeal-Schwenlder Corporation
email s_giang@mscsch.com
tel: 213 259 4967
From: tjgerman@53iss6.Waterloo.NCR.COM (Trevor German)
Newsgroups: sci.electronics
Subject: AMPERAGE
Date: 26 Aug 92 14:35:19 GMT
Organization: Imaging Systems Division, NCR Corp, Waterloo, Ont., CANADA


	re power supplies.

	As has already been stated the amp rating of a power supply (PSU)
	is the maximum rating. The actual current flow is always detemined
	by the load provided said supply can supply said load. If you
	attempt to take more than the rated current the supply woltage
	will drop below the specified tolerance band. That is if the
	PSU is 12V +- 10% with Imax of 2.5A and you attach a load of 3A
	the terminal voltage will fall below 10.8V (12V - 10%). Most 
	quality PSUs will however not allow you to do this and will
	current limit to prevent the PSU from overheating and failing.

	How much power is taken from the wall for a given load always
	depends on the efficiency of the power supply. A switching
	supply of 80% efficiency will take less power from the wall
	than a 50% linear supply. As follows


		Suppose the load takes 1A and the PSU is 12V

			Power consumed by load = 1A * 12V = 12W

			an 80% efficient PSU will consume

				12W * 0.2 W = 2.4W 

			a  50% efficient PSU will consume
	
				12W * 0.5 W = 6W

		Hence the 80% setup takes 14.4W from the wall
		while the 50% takes 18W.
	============================================================
 	Side note:- If you have the choice between two supplies that
			both can supply the load there are other
			factors to take into acount other than 
			efficiency.

	reliability:- Running a PSU at maximum load decreases the life
			expectancy of the unit.

	ripple and noise:- Running a psu at maximum load, will increase 
			the amount of ripple and or switching noise
			present at the terminals. This is because there
			is always a storage capacitor present which is
			being periodically discharged by the load. With
			small loads this discharge is less noticable.
			With audio and radio circuits this noise can be
			problematic.
	Physical size:- Like technology PSUs typically get  larger with
			Imax rating.

	Fault effects :- Running a 1A load with a 10A supply can be
			spectacular when a fault occurs. Smoke and flames.
			Use a fuse.
	===============================================================
 
			
--
       >| "Only average people           | Trevor J German BSc    |<
       >|       never make mistakes."    | NCR, Waterloo, Ontario |<
       >|	               	         | Canada.                |<
From: iordonez@academ01.mty.itesm.mx (Ivan Ordonez-Reinoso)
Newsgroups: sci.electronics
Subject: CCD Image Sensors
Summary: Help
Keywords: CCD, Image sensors
Date: 28 Aug 92 23:46:18 GMT

I am posting this for a friend, who does not have access to netnews. He
needs to have some information about the way the CCD Image sensors work,
and about places from which he might buy some CCDs that are not too
expensive. He would also like to see some designs of circuits able to
generate a frame from the analog signal that the CCD produces.

His name is Jose Lazaro Salinas. Please contact him at the following
e-mail address:

jsalinas@mitras.mty.itesm.mx

Thanks to all those who email Lazaro.

--Ivan Ordonez-Reinoso

Newsgroups: sci.electronics
From: dave@dlb.com (Dave Buck)
Subject: Re: Is there 9V size 9V Nicads?
Reply-To: dave@dlb.com (Dave Buck)
Organization: D.L.Buck & Associates, Inc.; San Jose, Calif.
Distribution: usa
Date: Thu, 3 Sep 1992 21:02:38 GMT

meric@leland.Stanford.EDU (meric ozcan) writes:

>The 9V size Nicads that I see are 7.2V or 7.5V. However manufacturers
>are smart enough to either not specify the voltage, saying that 9V
>size for 9V equipment, or print the voltage rating with a fine print.
>What I am looking for is 9V size Nicad with a voltage rating as close
>as possible to 9V. Does anyone know if this exist? Thanks.

>Meric
>meric@leland.stanford.edu

Here in the U.S., look for "Again&Again", SAFT America, Valdosta GA 31601.
Their's is 8.4V, up one cell from the 7.2V so commonly found.
Don't overcharge -- they pop, as the cells are packed in tight. (Still
usable after popping the case, I've found).
I buy these from Price Club.
-- 
Dave Buck   dave@dlb.com   {amdahl,ames,daver,netcomsv,sun,zygot}!dlb!dave
D. L. Buck and Associates, Inc.;   San Jose, California;    (408) 972-2825
Newsgroups: sci.electronics
From: kludge@grissom.larc.nasa.gov ( Scott Dorsey)
Subject: Re: Computer on a car battery
Organization: NASA Langley Research Center and Reptile Farm
Date: Mon, 31 Aug 1992 12:46:28 GMT

In article <1992Aug31.103541.23022@fokus.gmd.de> jet@fokus.gmd.de (J. Tiemann) writes:
>In article <IISAKKIL.92Aug30164509@vipunen.hut.fi>, iisakkil@vipunen.hut.fi (Mika Iisakkila) writes:
>|> jeffn@nuchat.sccsi.com (Jeff Noxon) writes:
>|> 
>|> >Question 1: How can I power the motherboard?  I am interested mostly in
>|> >efficency.  Would 5V regulator ICs do the job as well as anything?
>|> 
>|> Not really. I worked for a couple of years for a company that made
>   [...]
>|> that could deliver the rated voltages at as low as 5.2 V of input,
>|> although this requires some black magic. Low operating voltages are
>|> needed to keep the power supply working properly during engine start,
>|> which causes a severe drop in the battery voltage.
>
>There are also high voltage spikes that can damages the voltage regulator
>and the computer during engine starts. So you need a good filter (to filter
>the high frequencies from this spikes) protect the electronic. The high 
>currents during this time (from battery to the engine/generator) can also
>confuse your computer, but most trouble comes over the power supply.

I think the original poster wanted to run it off of a car battery (removed
from the car) and not from a car's electrical system.  In this case, just
a simple regulator should do the job, though you should make sure that if
you are trickle charging the battery while in use that the charger doesn't
throw a lot of noise into the system.

Also, you might be a lot better off using a marine deep-cycle battery, which
can withstand heavier charge-discharge cycles.  However, if this is a one
time application it might not be worth the added expense.
--scott
From: jdishaw@acme.claremont.edu
Newsgroups: sci.electronics
Subject: Looking for a schematic - Datapoint drive
Date: 26 Aug 92 00:31:53 GMT
Organization: Pomona College

Does anybody have the schematics for a 8" Datapoint floppy drive (Rev A)?

-James Dishaw
jdishaw@pomona.claremont.edu
Newsgroups: sci.electronics
From: wlsmith@valve.heart.rri.uwo.ca (Wayne Smith)
Subject: Re: <<<<<FOR SALE  68030 33MHz. - $300  shipping paid by me
Organization: The John P. Robarts Research Institute, London, Ontario
Date: Sat, 29 Aug 1992 00:18:42 GMT
Keywords: 68030

In article <1992Aug28.222006.11603@hamblin.math.byu.edu> richard@newt.ee.byu.edu (Richard Christensen) writes:
>
>I have a 68030 at 33 MHz chip.  I need to sell it
>for $300.  I'll pay shipping.  Nothing is wrong
>with it, I just can't use it.  I know that the 
>sample price is around this figure, so it should be a steel
>at this price.

Now here is an example of market forces at work.
Who uses the 68030?  A lot of closed-box-high-priced systems.   
And we're talking $300 just for the CPU.

Now look at the 80386 -40 (or Intel -33, whatever).
Who uses this CPU?  many many open MS-DOS/Unix/whatever systems.
Cost for the motherboard and CPU?  -> $225.

Class dismissed.
From: cb1p+@andrew.cmu.edu (Chris Beasley)
Newsgroups: sci.electronics
Subject: RE: New Sony 696HV VCR's for $329
Date: 26 Aug 92 10:34:06 GMT
Article-I.D.: andrew.4eawuSW00WB548g5o4
Organization: Carnegie Mellon, Pittsburgh, PA


Great!  So, just exactly what is a 696 and why 
should I get one?  Seriously, I am looking for
a VCR but I don't know the specs on this new unit.
B
Newsgroups: sci.electronics
From: jeffn@nuchat.sccsi.com (Jeff Noxon)
Subject: Re: Computer on a car battery
Organization: /etc/organization
Date: Mon, 31 Aug 1992 18:34:43 GMT

In article <BtuM5H.6My@news.larc.nasa.gov> kludge@grissom.larc.nasa.gov ( Scott Dorsey) writes:
>
>I think the original poster wanted to run it off of a car battery (removed
>from the car) and not from a car's electrical system.  In this case, just
>a simple regulator should do the job, though you should make sure that if
>you are trickle charging the battery while in use that the charger doesn't
>throw a lot of noise into the system.
>
>Also, you might be a lot better off using a marine deep-cycle battery, which
>can withstand heavier charge-discharge cycles.  However, if this is a one
>time application it might not be worth the added expense.

Actually, I planned on an automotive or marine battery connected to a 
dual battery isolator (the RV type sold at auto parts stores).  The dual
battery isolator allows the battery to charge when there is alternator
output but prevents the main car battery from being drained.  I haven't
looked at one closely yet, so I don't know if the power surges will be
a problem or not.

Thanks for the help, guys!

-- 
Jeff Noxon
jeffn@nuchat.sccsi.com
713/721-6820 CDT Houston TX
Organization: University of Illinois at Chicago
Date: Wednesday, 2 Sep 1992 10:25:57 CDT
From: Wesley Bielinski <U53734@uicvm.uic.edu>
Newsgroups: sci.electronics
Subject:    WANTED: Cheap CCD Camera Plans

Early this year I saw a posting for making a CCD camera from some type of
chip.  I am working on a 12" Newtonian telescope mirror and I would like to
have a CCD camera to take long "deep sky" exposures with it.
Can someone help me out?   Thank you

Wesley J. Bielinski     U53734@uicvm.uic.edu
SGT, USAR
12th Special Forces Group (Airborne)
From: mycal@netronix.com (Mycal Johnson)
Newsgroups: sci.electronics
Subject: CATV DECODERS ??? 
Distribution: world
Date: Thu, 03 Sep 92 17:24:47 GMT
Organization: Netronix, Inc.


In article <geb1.715470002@Isis.MsState.Edu> geb1@ra.msstate.edu writes:

  > 
  > Can anyone explain how these Scientific Atlanta Cable boxes can talk 
  > back to the cable company?

Simple, they can't.  Unless there like the Tocom with the phone line pluged
in to them.  But the ones I've seen, 8500,8536,8580's can't, don't.

  Also I see these "TURN-ONS" in R-E for certian
  > cable boxes, do they really work??

They can, but buyer beware, somtimes they don't go in that easy, because
of different rev's of the box, etc.

  >
  > geb1@ra.msstate.edu
  > 
-----------------------------------------------------------------------------
                                     ?
Pirate Radio?  Whats that?        @ o o @                mycal@netronix.com
                                     O

                            Just Say Know to Drugs.
From: exumfox@exu.ericsson.se (Mike Fox)
Newsgroups: sci.electronics
Subject: Re: VIDEOCYPHER II/IIPLUS/RS
Date: 26 Aug 92 21:34:43 GMT
Reply-To: exumfox@exu.ericsson.se
Organization: Ericsson Network Systems


VCII - this data stream is being shut off as we speak
       and the tecnology is moving to VCII+. Too many
       hacks broke the code.

VCRS - Not really used yet, however it is available.
       RS - renewable subscription - the module has  
            a 'card reader' on it.

The modules aren't cheap (>300) and are required for
use in the receiver for you to be able to subscribe
to commercially available scrambled channels.

You will also see these acronyms

CSPP consumer safety protection plan - 3 year guarantee
     on the module from GI if they change scrambling
     technology you get a free upgrade (if your box
     hasn't been tampered with)

MOM - Modem on Module - able to call in for pay per view
     through on-screen programming.

Try rec.video.satellite FAQ for further info.
From: whit@milton.u.washington.edu (John Whitmore)
Newsgroups: sci.electronics
Subject: Re: <<<<<FOR SALE  68030 33MHz. - $300  shipping paid by me
Keywords: 68030
Date: 2 Sep 92 22:22:08 GMT
Article-I.D.: u.1992Sep2.222208.16332
Organization: University of Washington, Seattle

In article <1992Aug29.001842.163@julian.uwo.ca> wlsmith@valve.heart.rri.uwo.ca (Wayne Smith) writes:
>In article <1992Aug28.222006.11603@hamblin.math.byu.edu> richard@newt.ee.byu.edu (Richard Christensen) writes:

>>I have a 68030 at 33 MHz chip.  I need to sell it
>>for $300.

>Now here is an example of market forces at work.
>Who uses the 68030?  A lot of closed-box-high-priced systems.   
>And we're talking $300 just for the CPU.
>
>Now look at the 80386 -40 (or Intel -33, whatever).
>Who uses this CPU?  many many open MS-DOS/Unix/whatever systems.
>Cost for the motherboard and CPU?  -> $225.

	The lesson: a part like the 80386, which is generic (and available
from two independent sources, AMD and Intel) is less expensive than
a part like the 68030, which is not available in a 'clone' from
any second source.

	Anyone else want to start up an 'Open Hardware Foundation'?

	John Whitmore
Newsgroups: sci.electronics