HDTenEightyP/NetNews huggingface dataset:
From: cd1i+@andrew.cmu.edu (Christopher Bradley Devlin)
Newsgroups: sci.electronics,rec.autos.tech,sci.energy
Subject: Re: Flywheel batteries as EV power source
Date: 18 Dec 92 06:31:41 GMT
Article-I.D.: andrew.gfATnhq00iUzI1mV0H
	<1992Dec15.194558.2556@adobe.com>
Organization: Fifth yr. senior, Materials Science and Engineering, Carnegie Mellon, Pittsburgh, PA

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

What is all this talkk of particles blowing through the housing?  What
particles?  The original premise was that these flywheels disintegrate
into a light cotton like fiber.  Heat, yeah, but how much kinetic energy
does a flying piece of cotton have?
And there are ways of dealing with too much heat.  How about ceramic
thick films on the inside of the housing as thermal sheilds?  Or a
ceramic housing?
I think I'll look these up, does anyone have a reference?

Chris
Newsgroups: sci.electronics
From: swifty@tc.fluke.COM (Steve Swift)
Subject: Re: Request for information about TEMPEST
Organization: John Fluke Mfg. Co., Inc., Everett, WA
Date: Fri, 11 Dec 1992 20:08:58 GMT

In article <1g4i1mINN77f@urmel.informatik.rwth-aachen.de> zhang@rwthi3.informatik.rwth-aachen.de writes:
>Can anybody tell me how I can get as much information as possible about
>TEMPEST (Transient-Electro-Magnetic Pulse Emanation Standard)? I have no
>idea about it. Can anybody recommend some books, papers, and the names of
>conferences? Any information is appreciated.
>
>Thanks in advance.
>
>
>---
>Xiaoming, ZHANG                  E-Mail: zhang@rwthi3.informatik.rwth-aachen.de
>Lehrstuhl fuer Informatik III    Tel.: +49-241-8021314 (Office)
>RWTH-Aachen                            +49-241-873751  (Home)
>Ahornstrasse 55                  Fax.: +49-241-8021329
>W-5100 Aachen
>Germany
>

I believe that most of TEMPEST is classified.  At least it was
last time I worked on a TEMPEST rated product.  Since I didn't
have a clearance, I had to design the unit, but someone else
had to do the test.  All I got back was "it passed, it failed."
Never why or what to do.

-- 


            Steve Swift, Sr. Staff Engineer
    Domain: swifty@tc.fluke.COM
    Voice: (206) 347-6100, Ext. 5737 direct: 356-5737
    FAX: (206) 356-5108
    UUCP: {uw-beaver,microsof,sun}!fluke!swifty
US mail: John Fluke Mfg. Co./ P.O. Box 9090/ MS 266D/ Everett WA  98206
From: system@hale.cts.com (System Administration)
Newsgroups: sci.electronics
Subject: Lasers and Servos, Sources?
Date: Sat, 12 Dec 92 17:16:06 PST
Organization: Hale Telecommunications Inc.


Hello--

I'm looking for sources for small lasers and hardware for
show use, hopefully cheap enough for mere mortals like myself.

12 Volt based systems prefered.

I work for the corporate office of a chain of stereo shops,
this is an idea I was kicking around on my own for
flashing product logos etc. on the walls.  The owner is big on neon,
I think he'd go for this if I can get a working setup on my own first.
From: tmis1692@altair.selu.edu
Newsgroups: sci.electronics
Subject: Magnavox 286 Computer - Video problem. 
Date: 14 Dec 92 10:35:12 -0600
Keywords: Magnavox 286, Video
Distribution: world
Organization: Southeastern Louisiana University

Can you override the video on a Magnavox 286 motherboard by plugging a VGA card
in one of the expansion slots?  Does the system recognize the plug-in board as
the video card it's supposed to use?  The video is acting goofy.  I swapped
monitors and that's not the problem.  Looks like the video card.  I understand
that Magnavox video is on the motherboard so I want to fix the video problem by
using a VGA card in one of the expansion slots.  Can it be done?

Thanks, 

Kevin - TMIS1692@selu.edu

Xref: sparky sci.electronics:21247 sci.energy:6302 rec.autos.tech:16984
From: rubin@grape.cis.ohio-state.edu (Daniel Rubin)
Newsgroups: sci.electronics,sci.energy,rec.autos.tech
Subject: Re: Flywheel batteries as EV power source
Date: 21 Dec 92 00:49:47 GMT
Organization: The Ohio State University Dept. of Computer and Info. Science

>It depends on how fast you release the energy. A damaged flywheel will
>release all its energy at once. A tank of gasoline by itself will not
>explode in a collision, despite what you see in the movies.
>
>Why don't you go buy a gallon of gasoline in a metal container, take it
>as high up as you want, and drop it. It will not explode. It might
>splatter, but it will not explode.

OK I agree that cars do not expode like seen on the big screen.  A car
can expolde though.  Take the above example and add a high amperage electrical
system and loads of wires to the top of the gallon of gas.  Now if the
conditions are good the gas will spatter the vapor will come in to contact
with a spark from two shorting wires and you will get a nice explosion.  
Fuel-Air explosions are quite nasty.  Buring gas will not do that much, but
produce heat, whereas buring gas vapor mixed with oxygen in the air will
produce a powerfull explosion...

Try it.  Drip a few drops of gas in a fire pit or some other similiar type of
open ended enclosure ( no more than 5 or 10 drops of gas ).  Wait for it to
vaporize and then throw a match in.  Whooomppp you will feel the shock wave
and it most likely with scare the sh-eck out of you...

>You can also try shooting it with a rifle or whatever. I have.
>It's pretty boring.

This can cause a rather large gas vapor cloud with the first shot assuming it
is a high enough power rifle to rupture the container somewhat.  If the 
container is steel and the bullet is steel a second shot should knock your
socks off...

>>>Unless you wrap the flywheel in a massive enough container that it can absorb
>>>all that energy without vaporizing, you're going to have an explosion.
>>
>>Why bother, we don't wrap our gas tanks in a container that would contain
>>their explosion?
>
>Because gas tanks don't explode. Movies are not reality.

Car crashes violently, gas tank is ruptured and gas is forced out of the 
rupture by the crash.  Gas vapor cloud forms rapidly and comes in contact 
with the shorting positive battery post agains the frame of the car.  That
will cause a rather large explosion and quite a lot of fire.  This would
be a rare case and the individual would most likely not survive the crash
itself...

>-- 
>My opinions are my own.
>

                                                                  - Dan
-- 

             Daniel Joseph Rubin     rubin@cis.ohio-state.edu 
     
                       GO BENGALS!      GO BUCKS!
Newsgroups: sci.electronics
From: mce5921@bcstec.ca.boeing.com (Martin Emde)
Subject: Walkman Modification
Organization: Boeing
Date: Wed, 16 Dec 1992 20:36:33 GMT

Does anyone know how to modify a simple walkman FM receiver to operate
in the 108-136Mhz range (aircraft voice communications) or know if 
something like this is even possible?

If so I would like to know ...

Thanks,

-Martin

-- 
Martin C Emde  <mce5921@bcstec.boeing.com>  uunet!bcstec!mce5921 
Boeing Commercial Airplane Group - 777 Electrical Systems
Renton, Washington  USA
Newsgroups: sci.electronics
From: lsg001@cck.coventry.ac.uk (Graham Wilson)
Subject: charging question
Organization: Legal Department - Coventry University
Date: Thu, 17 Dec 1992 14:23:26 GMT



If you have a bank of 12 volt batteries of 500 amp capacity, what is the 
highest amp hour charge you can put into the batteries without cooking
them ?


Is there are a formula for working this out ?



Thanks.





-- 
         *********************************************************
         *      Graham Wilson      *  lsg001@cck.coventry.ac.uk  *
         *     LL.B.  Law  III     *     Coventry  University    *
         *********************************************************
Newsgroups: sci.electronics
From: cmwolf@mtu.edu (christopher m. wolf)
Subject: Re: Flywheel batteries as EV power source
Organization: Michigan Technological University
Date: Tue, 15 Dec 1992 00:49:56 GMT

jeh@cmkrnl.com writes:
>To be usable for an electric vehicle, you need a massy, large-diameter flywhee
>that spins at phenomenal speeds.  It is made with high-tech materials (carbon
>fibers, that sort of thing) so that it won't tear itself apart.  It must be
>spun in a vacuum chamber or else a lot of the stored energy goes to heating th
>air.  It must be Floated on near-frictionless bearings, such as magnetic
>bearings, and coupling to the outside is via a magnetic clutch (ie the flywhee
>shaft does not extend outside the enclosure).  
>
>The flywheel must be arranged with a vertical axis so that gyroscopic effects
>don't make it impossible to turn the car.  Still, you need to worry about thes
>effects whenever the car enters a sharply-banked road or freeway ramp.  

The same flywheels are referenced in the last IEEE.  They are low mass, very 
high speed devices.  The low mass does not obstruct cornering, while the
high speed and low diameter helps them to store more power.  They supposedly
should take about 10 minutes to fully "charge", given a large enough (not
impossible) power source, although usually not available in the normal home.
They should be made of a composite fiber material, so if they should break 
apart, they will basically turn into something resembling cotton, instead of
destroying everything around it.  Several of these would be needed.  The 
magnetic bearings would supposedly allow them to spin for months if not
being used.

From: ryoung@pollux.svale.hp.com (Roderick Young)
Date: Thu, 17 Dec 1992 23:40:42 GMT
Subject: Re: Capacitor Question
Organization: Hewlett Packard CPCD, Sunnyvale CA
Newsgroups: sci.electronics

Re: equalizing resistors across series capacitors.

I'll use rough values.  You have two 500 uF capacitors in series, with
about 500V across them, total.  That's at least 250V across one of them.
A 100-ohm resistor here would burn an incredible 625 watts.

I would try paralleling about 500k across each capacitor, and then
testing the voltage in service to see if the capacitors have approximately
equal voltages across them.  If not, then lower the resistor values,
keeping in mind that V**2/R is the power running through the resitors.
You may need to use high wattage resistors.
From: grego@bit.UUCP (Greg Sanguinetti)
Newsgroups: sci.electronics
Subject: Re: Various national colour code of wires (e.g. earth) for elec. plug
Date: 14 Dec 92 17:59:59 GMT
Article-I.D.: bit.531
Reply-To: grego@bit.UUCP (Greg Sanguinetti)
Organization: BIT  Portland, OR

In article <1992Dec14.133335.21707@cs.hw.ac.uk> adrian@cs.hw.ac.uk (Adrian Hurt) writes:
>In article <519@bit.UUCP> grego@bit.UUCP (Grego Sanguinetti) writes:
>>Anybody reading sci.electronics should have more than enough basic knowlege
>>to figure out house wiring.
>
>Perhaps not - just because one subscribes to a newsgroup does not mean that one
>knows as much as the rest of the readers of that newsgroup.  Otherwise, the
>
Probably correct, but house wiring has to be one of the most rudimentary
forms of electronic circuits. One should not be affraid of it simply because
there is a governmental agency involved. One should take care and follow the
rules and have the work inspected, just as you would have a design review
at work.

In the US, most electrical inspectors (from the local building department)
are very helpfull and are available to ask questions, make suggestions,...
Also I have heard of a number of electricians that will work with the
home owner. That is a great way to learn the extra little tricks.

In the US, you don't need a special license but you do have to get a permit
and get the work inspected. I like that system. All the parts are available
at most hardware or "home improvement" stores. They even provide do it
yourself booklets.

I think it's great that Brendan took it upon himself to get a license and
wire his own home. I encourage others to do the same. It's WONDERFUL to
have the right outlets exactly where you want them! Especially in my
workshop.
>>Anyway, the color codes you described are unfortunately opposite US N.E.C.
>>codes and are therefore very dangerous to use.
>
>That's probably because Brendan, judging from the "In article ..." line, is
>in Australia.

Yup, I should have said "dangerous to use in the US". I just wanted to warn
that the codes were unfortunately different and dangerously different.

-grego (may all your service entrants be underground)
-- 
---------------------------------------------------------------------------
Grego Sanguinetti, Bipolar Integrated Technology | Water, water everywhere,
grego@bit.uucp or grego%bit%ogi.cse.edu          | but I'd rather drink
or bit!grego@ogi.cse.edu or ...!ogicse!bit!grego | beer.
Xref: sparky sci.electronics:20789 comp.robotics:2649
From: rodb@cs.ubc.ca (Rod Barman)
Newsgroups: sci.electronics,comp.robotics
Subject: Shaft Encoder Counter Chips
Date: 15 Dec 1992 22:23:57 GMT
Organization: Computer Science, University of B.C., Vancouver, B.C., Canada
NNTP-Posting-Host: swan.cs.ubc.ca

Can anyone reccommend a good encoder counting chip?  I have used
the HP HCTL-2020 in a previous design but I would perfer something
that can either count more than 16-bits or could count
more than one channel. 

Thanks --rod.
--
--
Rod Barman, IRIS NCE @ Laboratory for Computational Intelligence, 
University of British Columbia
rodb@cs.ubc.ca
From: fmg@alpha.smi.med.pitt.edu (Filip Gieszczykiewicz)
Newsgroups: sci.electronics
Subject: [Q] + Re: "The Glob" Atari 2600 processors ???
Summary: One word: greed
Date: 17 Dec 92 16:43:01 GMT
Followup-To: sci.electronics
Distribution: na
Organization: Medical Informatics

EAO102@psuvm.psu.edu (Ernie Oporto) writes:
>Heh...I believe that's some wax, or something like that,
>covering the processor.  I opened up a really cheap
>calculator to catch a glimpse at its insides, and it was
>how you described it...a plastic glob.  Guess they don't
>want you fidlling with their processor, but I think they
>also have that there to tell if you voided your warranty
>by pulling the glob off to get at the processor yourself.

	Greetings. Nope.... there is something far greater behind this:
	greed. You see, the silicon chip is bonded to the PCB, all the
	wires are then bonded from the chip to the traces, and the whole
	thing is potted with a drop of "stuff"... No need for soldering,
	packaging, assembly, weight, size and most important, lower CO$T!
	(Take a look at any el-cheapo LCD watch gut!)

	Take care.

	P.S. Also, since there are less connections (solder, etc), the
	reliabity is higher for this method. What I'm wondering: Why are
	SIMMs made from individual chips on a PCB - why not do the above?
	I guess one thing would be thermal concerns (silicon expanding
	at a different rate than potting "stuff" and connecting wires
	shearing off... but there must be a better reason! Anyone know?
-- 
+------------------------------------------+----------------------------------+
| Filip "I'll buy a vowel" Gieszczykiewicz | Best: "fmgst+@pitt.edu"          |
| "If I feel that I've made this world a   | Or: "fmg@alpha.smi.med.pitt.edu" |
| better place, I will die content." - Me  | Ftr wnr f TLJ Rsrch!             |
From: dbak@elm.lle.rochester.edu (Douglas Baker)
Newsgroups: sci.electronics
Subject: Can Cable TV Descramblers really be detec from outside ???
Date: 21 Dec 92 00:23:12 GMT
Organization: University of Rochester, Rochester NY



In our local paper there has been talk of detecting Il-legal cable TV
descrablers from outside the home.  I can think of two possible ways
this can be done but there may be others.

        1) use a sensitive spectrum analyzer to find out which channel
is being watched by looking at the local oscillator freq.

        2) modulate a signal into the channels which aren't part of
basic and when these pay channels are watched the signal would be
radiated out the picture tube and detected.

        If anyone knows if any of the above methods are used or how
this is done could you reply to the net ?  I'm sure many others out
there will be interested.
From: slovell@milton.u.washington.edu (Sherman Lovell)
Newsgroups: rec.radio.amateur,sci.electronics
Subject: IRF 511 as RF Power Amp
Date: 13 Dec 92 04:19:36 GMT
Article-I.D.: u.1992Dec13.041936.15826
Reply-To: slovell@u.washington.edu
Organization: University of Washington, Seattle



	In the April '89 QST Doug DeMaw wrote about using 
the IRF 511 Mosfet as a RF Power amplifier.  Wes Hayward then 
wrote an excellent follow-up article in the Nov '89 QST.  I'm 
wondering if anyone has experimented with these transistors and 
circuits.  Specifically,  I'm puzzled by the fact that neither 
DeMaw nor Hayward seems to have run into trouble with these 
transistors' considerable input capacitance -- the 511 has about 
100 pF and the IRF 530 that Hayward used has about 900pF!  
When I build the circuits in these articles this capacitance looks 
like a .001 uF shunt across the input.  Even the 511's lower input 
C is hardly insignificant -- it looks like 150 ohms Xc at 7 MHz.  Is 
there something I'm missing here?  Hayward and DeMaw 
blithely put a 50 ohm resistance across the input, or a 200 ohm 
one with a 4:1 transformer and seem to have no problems.  
When I do the same thing my little QRP rig sees the 50 ohms in 
parallel with a big capacitive shunt, producing something far 
from 1:1 input swr.
	Also, any thoughts, anecdotes, or suggestions regarding 
these transistors' tendency toward self-destruction from static 
electricity, too high Vgs, and parasitic oscillations?
	Thanks for your help.
	Sherm Lovell, WY7F
Newsgroups: sci.electronics
From: morrison@cs.uiuc.edu (Vance Morrison)
Subject: Re: Flywheel batteries as EV power source
Organization: University of Illinois, Dept. of Comp. Sci., Urbana, IL
Date: Wed, 16 Dec 1992 17:23:13 GMT

Ligon@macgw1.ge.com (Woody Ligon) writes:

>If such effects are significant they could be, I suppose, an additional
>selling point both in terms of ride quality and safety. 

>I am assuming of course that the flywheel axle is vertical and the plane of
>rotation is horizontal. 

>Also wouldn't it seem that the gyroscopic effects would put terrific
>strains on the flywheel bearing systems whenever the car hit a bump in the
>road?  And how do you make a bearing strong enough to take that beating and
>still be extremely low friction?

Actually, the rotational inertia is not really the big problem with flywheels.
First of all, if you do it right, the inertia can help, not hurt (mounting
the flywheel horizontally will keep the car from tipping left to right
or up and down, which is desirable (just the wheels move up and down)).

If you REALLY don't want the angular inertia, you can get rid of it one
of two ways.  First, you could mount the flywheel in a gyroscope.  Thus
the flywheel simply moves without effecting the car.  This also removes
flywheel axial loads.  The other possibilty is to have to counter-rotating
flywheels.  In this case the angular inertia cancels out (there is high
axial load between the two flywheels, however).  

The REAL problem with flywheels is safety and weight.   Remember that a
flywheel has the energy equivalent of gallons of gasoline.  If you were
in a accident, this energy could all be release suddenly.   Thus there
MUST be some sort of containment system to insure that even in the worst
case the flywheel does not turn into a very large hand grenade.  This
can be done, but the containment system adds even more to the cost and
weight of the system.  Since flywheels are not the greatest in terms of
energy density to begin with, this is not good.

It seems to me that flywheels DO have good potential in small, stationary
applications (for example storing PV solar electricity during the day
for use at night, here weight is not a problem, and the flywheel's
VERY long life is a major advantage).  

Vance
From: rla@rahul.net (Bob Armstrong)
Newsgroups: sci.electronics
Subject: Electronics surplus places in Indianapolis
Date: 16 Dec 92 07:30:33 GMT
Distribution: usa
Organization: a2i network


  I will be visiting Indy next week (used to live there once upon a
time :-) and I wondered if there are any good electronics surplus places
worth visiting.

THanks,
BOb Armstrong
rla@rahul.net

-- 
Bob Armstrong <rla@rahul.net>
Xref: sparky sci.electronics:21243 sci.energy:6301
From: carl@SOL1.GPS.CALTECH.EDU (Carl J Lydick)
Newsgroups: sci.electronics,sci.energy
Subject: Re: Flywheel Failure
Date: 20 Dec 1992 23:45:48 GMT
Organization: HST Wide Field/Planetary Camera
Distribution: world
Reply-To: carl@SOL1.GPS.CALTECH.EDU
NNTP-Posting-Host: sol1.gps.caltech.edu

In article <1992Dec18.213437.27052@adobe.com>, pngai@adobe.com (Phil Ngai) writes:
=In article <57411@olivea.atc.olivetti.com> fredl@strobe.ATC.Olivetti.Com (Fred Leffingwell) writes:
=>	So Is the real reason for not storing energy in a flywheel
=>	the danger?  If so why the comments that the things simply
=>	fail in a cotton candy like fluff?
=
=Ah, the fluff argument again.
=
=Would you agree that a gas is even less dangerous than cotton candy?
=
=Now, let me expose you to a blow torch. It's only hot gas, right?

Hell, expose him to a fuel/air bomb using 2 gallons of gasoline as the fuel.
It's only gas, and has about as much energy as the flywheels under discussion.
Only a little breeze.  Couldn't possibly hurt him.  I'd recommend that you
conduct this little experiment at a distance, though.
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: CARL@SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL

Disclaimer:  Hey, I understand VAXen and VMS.  That's what I get paid for.  My
understanding of astronomy is purely at the amateur level (or below).  So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it.  If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.
Newsgroups: sci.electronics
From: ray@ole.cdac.com (Ray Berry)
Subject: color codes on TO-92 pkgs
Organization: Cascade Design Automation, Bellevue, WA
Date: Thu, 17 Dec 1992 21:15:06 GMT

    The rounded side of many TO-92 pkgs has a 3-stripe color code.  Does
anyone know the significance?  Is the usage uniform between mfrs?
-- 
Ray Berry kb7ht ray@ole.cdac.com 73407.3152@compuserve.com /*inquire within*/
From: Brian_-_Dziki@cup.portal.com
Newsgroups: sci.electronics
Subject: SPICE models
Date: Fri, 11 Dec 92 21:22:31 PST
Organization: The Portal System (TM)

    I was wondering where one might find SPICE models for transistors. We have
IsSpice at work, but the library does not include the transistors that we ne
model. Is there an Internet site where one my find them?


                        Thanks,
                         Brian Dziki
From: vnelson@ccu.umanitoba.ca (Gerald Vernon Nelson)
Newsgroups: sci.electronics
Subject: Re: Transmission line question
Date: 21 Dec 92 03:39:46 GMT
Organization: University of Manitoba, Winnipeg, Canada

In <1992Dec15.202004.15878@ucsu.Colorado.EDU> barr@tramp.Colorado.EDU (BARR DOUG) writes:

>Some specs I have call for ethernet coax to be grounded in one location
>and one location only! I am wondering why this is. Antenna effects,
>current loops or something else. Does anyone know why this is the case?


Ground loops.  If you grounded a piece of coax at two ends of a building,
the grounds may not be at the same potential.

If you check, you will find that the BNC connectors are not connected
to the chassis of the P.C.  The whole line is grounded at one point.

Vern Nelson
Newsgroups: sci.electronics,comp.robotics