HDTenEightyP/NetNews huggingface dataset:
From: andy@laguna.santafe.edu (Andy Mell)
Subject: Re: Connecting multiple strobe lights
Date: Mon, 04 Jan 93 19:52:55 GMT
Organization: Santa Fe Institute

In article <C0Bo01.Gus@news.cso.uiuc.edu> lnosek@ux4.cso.uiuc.edu (Luke Nosek) writes:
>
>	I have these three strobe lights and I want to make them flash
>synchronously, with minimum interconnection. Here is the schematic -
>I may have interpreted wrongly so feel free to tell me if something doesn't
>make sense:
>

Commercial disco strobes do not work like this, if you have a chain of say
200 strobe tubes around a dance hall they have to be easily triggered.
If you want to maintain compatability with the industry you should allow for
a cannon XLR connector on the back of your strobe, two - one for in and
one for out  The strobe should be configured to flash on every single
positive going edge recieved between pins 1 &2 on the XLR, max voltage is
about 5-10 V, but not fussy. So you would need a circuit that discharges the
tube on every 5V spike received.

Advantage of doing it this way is that you maintain compatibility with 
strobe controllers/chasers that are used in the industry.

Andy

-- 
-------------------------------------------------------------------------------
Andy Mell, Applied Physics Department,  |   andy@santafe.edu
University of Hull, Hull, HU7 6RX       |   amell@nyx.cs.du.edu
England.                                |   torq@gnu.ai.mit.edu
Newsgroups: sci.electronics,rec.music.synth,comp.music
From: mxd7977@ultb.isc.rit.edu (ELECTRONIC MUSICIAN)
Subject: HELP! Adding Battery Back-up
Originator: mxd7977@ultb
Organization: Rochester Institute of Technology
Date: Thu, 7 Jan 1993 16:05:27 GMT

I am trying to add battery backup to one of my sound modules, and I was
wondering just how difficult or more precisely what the best way is to
go about it.  From what I understand, you locate all temporary memory
IC's disconnect the +5 from them, and then attach their power lines to a
circuit which switches between normal operating voltage during power up
situations and a 3.3 volt lithium during power down situations....is
this a correct assumption?  And if so what do you think the best
configuration is? Should I use a zener with a voltage comparator which
switches off the normal power and on the battery by way of diodes when
the voltage drops too low?  Any insight would be much appreciated.  I am
a computer engineer, but haven't had much exposure with battery backed
up ram systems (at least not at this level...)


Thanks,
E. M.
From: cyberman@toz.buffalo.ny.us (Cyberman)
Newsgroups: sci.electronics
Subject: Tube Amplifier Design Questions
Date: 1 Jan 93 17:14:10 GMT
Organization: The Tower of Zot - (716)8338-616

Ok since I would like to construct a tube amp for a freind with a rated 
output of about 200 watts.  I thought I would ask the net for wisdome.

Ok what "brand" and "type" of tubes are the most dependable?
Since I'm a BJT and Fet person tubes are a change.  
I  understand the principle of  the beasts but what are the typical
control voltages?  Common dependable design?

I take it there are tube equivalents of the ephemeral emitter follower 
circuit.  

Any suggestions for books (preferably after 1980 but I don't expect 
many/any).
Cyberman
T HANKS
?S

************************************************************
* Cyberman@TOZ.BUFFALO.NY.US                               *
*   "Life is what you put into it" - Cyberman              *
* Optimistic - running through a barn of manure looking    *
* for the horse!  /\ [] ( )                                *
Newsgroups: sci.electronics
From: srfergu@rufus.erenj.com (Scott Ferguson)
Subject: NEC 5-Band EQ-on-a-chip
Organization: Exxon Research & Engineering Co.
Date: Wed, 6 Jan 1993 19:01:41 GMT

Has anyone used the NEC (forget the number) 5-band EQ chip? Would
it make a good quality yet affordable eq section for a home-made
audio mixing console? Let's say for 12 or more channels.

Anyone know what else it needs to complete EQ? Ideally it'd need only
5 potentiometers, but I get the feeling a chip like this might require
capacitors to choose cutoff frequencies, etc.

Thanks a lot.

-- 
----------------------------------------------------------------------
Scott Ferguson                        Exxon Research & Engineering Co.
Project Engineer                      New Jersey
----------------------------------------------------------------------
"Always bark at a dog."
From: dpd007@bcsaic.boeing.com (Mark Standiford)
Newsgroups: sci.electronics
Subject: Tube info needed
Keywords: TRIODE POWER TUBES
Date: 10 Jan 93 22:29:13 GMT
Organization: Boeing Computer Services, Seattle

I have recently become the owner of five Amperex 5868 tubes. 
These are big power tubes, I think they are triodes.  I want 
to use them to make a powerful ultrasonic cleaner but I can't
seem to find any reference to pinout or ratings.

If some kind soul could email me any info on these tubes 
(esp filament voltage, current and maximum voltage) I would
really appreciate it.

Please mail me at dpd007@atc.boeing.com as I don't often
get to this group.

Thanks in advance...


Newsgroups: sci.electronics
From: ces@cs.uwa.oz.au (Cesar Bertino)
Subject: CCD imager info
Organization: Dept. Computer Science, University of Western Australia.
Date: Tue, 12 Jan 1993 05:43:20 GMT

Does anybody know of a commercially available CCD imager that can do:

* full frame capture (i.e. non-interlaced video)
* electronic shutter speed

I am doing work in computer vision and I would need such a device to
capture still pictures of moving objects and hence the interlaced video
where half the frame is 1/60 secs appart is not satisfactory for my
application. If anybody knows of a CCD imager IC or video camera that can do the
following I would like to hear from you.


Thanks in advance.

Ces Bertino	(ces@cs.uwa.edu.au)
		Department of Computer Science
		The University of Western Australia
Newsgroups: sci.electronics
From: mgc@unislc.uucp (Marc Christensen)
Subject: Re: IR remote control summary!
X-Newsreader: TIN [version 1.1 PL6]
Organization: Unisys Corporation SLC
Date: Tue, 5 Jan 1993 16:40:44 GMT

Matthew A. Skala (ua123@freenet.victoria.bc.ca) wrote:
: 
: 
: Many thanks to all who sent me info on IR remote controls for VCRs. 
: Here's a summary of the information I got:
: 
: brianr@tekig1.pen.tek.com (Brian Rhodefer) says that Radio Shack makes an
: IR receiver module that could be used - it contains a phototransistor,
: tuned amplifier, and demodulator that operates at 40 kHz.
: 
: bbs.haymore@tsoft.net (Ed Haymore) says that his friend was experimenting
: with this sort of thing and most VCRs used a carrier frequency of about 38
: kHz, digital on-off-keying modulation.
: 
: jmorriso@ee.ubc.ca (John Paul Morrison) says that most VCRs use digital
: pulses of 40 kHz carrier.
: 
: So based on this information, it sounds like a frequency of 40 kHz is
: pretty standard as a carrier.  So what I plan to do is use a 567 tone
: decoder to demodulate the signal,
Forget this and use the Sharp I/R demodulator from radio shack.
They cost USD$3.50. 
they only have 3 pins to connect. +5v, Ground, TTL data out.
Before I found these modules I had a hard time getting any kind of range out
of my demodulator.
the module I tested had better range than any of my equipment with remotes.
I you can't get these modules I can send you some if you like.

: 555 to modulate, when sampling just
: time-stamp the edges of the modulation and play that back into the 555 at
: 40 kHz.  This is very short-range, so it doesn't matter if the transmit
: frequency is a bit off and is just on the edge of the VCR receiver's passband.
: 
Marc Christensen
From: ornitz@kodak.kodak.com (Barry x24904/ER/167B-TED)
Newsgroups: sci.electronics
Subject: Re: Microwave Oven Plasma Etcher?
Keywords: microwave, Reike and Hartree diagrams, Gerling Labs
Date: 6 Jan 93 16:01:07 GMT
Followup-To: sci.electronics
Organization: Eastman Chemical Company

In article <15340.2b4a1345@ohstpy.mps.ohio-state.edu> 
edharris@ohstpy.mps.ohio-state.edu writes:
>I'd like to use a small microwave oven ( will a small vacuum chamber inside) 
>to generate reactive plasmas ( O2 etc) for cleaning and etching in our lab. 
>The idea sort of works, but even the smallest ovens  (400 Watts or so) 
>generate so much heat that they tend to burn samples more than etch them...
>Does anyone know how to lower the power output of the magnatron, or is it
>possible at all? I'd like to cut the power to 50W or so...

Reducing the power of a home microwave oven is not practical.  These things are
designed to operate full on or full off.  Their power supplies usually use
special transformers with high leakage reactance to limit the current so if
you change the tube operating conditions much, you will have to come up with a
new power supply too.  Magnetrons designed to operate over wide power ranges
usually use external electromagnets so you can adjust the field as the voltages
are varied.  A company in California, Gerling Labs (recently sold to another
company but I cannot remember the name), makes a nice variable power microwave
system with waveguide output, directional power sensors, etc. rated for a few
watts to 3 KW.  It is probably overkill for your application. Finding Reike and
Hartree diagrams for the tubes used in home ovens will be necessary if you
plan to modify the power supply in your home-style oven.

A simple suggestion would be to place a few beakers of water in your oven
along with your etch cell.  Much of the energy would go into heating the water.

					Barry
 -----------------
|  ___  ________  |    Dr. Barry L. Ornitz          WA4VZQ
| |  / /        | |    Eastman Chemical Company
| | / /         | |    ECC Research Laboratories, Engineering Research Div.
| |< < K O D A K| |    Process Instrumentation Research Laboratory
| | \ \         | |    P. O. Box 1972, Building 167B
| |__\ \________| |    Kingsport, TN  37662  (615/229-4904, FAX 615/229-4558)
|                 |    INTERNET:   ornitz@kodak.com
 -----------------
From: lihan@ccwf.cc.utexas.edu (Bruce G. Bostwick)
Newsgroups: sci.electronics
Subject: Re: Where to mount an outside temp probe on a car?
Date: 4 Jan 93 18:49:05 GMT
Reply-To: lihan@ccwf.cc.utexas.edu (Bruce G. Bostwick)

In article <1993Jan4.134028.27684@phx.mcd.mot.com>,
schuch@phx.mcd.mot.com (John Schuch) writes:
|>In article <1993Jan4.002944.6494@sequent.com> washer@sequent.com (Jim
"Throw it over the wall" Washer) writes:
|>>I'd like to mount a temp probe on my car to sample the air temp. I'd like
|>>to get as accurate a reading as possible (without exceeding some reasonable
|>>cost).
|>>My biggest concern is getting false reading if the probe gets wet, and reads
|>>too low due to evaporation..
|>>Has anyone done this? Where did you mount the probe... How did you
protect it?
|>
|>I think I'd try either in the trunk, or inside one of the tail-light
|>assemblies first. At sixty miles per hour, the airstream hitting the
|>sensor will cool it nearly as much as being wet. You need to find
|>someplace outside of the airstream, where it wont get wet, and it's
|>not near any heat source.

BZZZT!   He _wanted_ the air temperature -- which means he _wants_ _maximum_
"cooling" of the sensor.

Having done this very thing on a Radio-Shack sort of level, I would recommend
mounting the sensor at the very front of the car, as far in front of the bumper
as you can mount it without being embarrassed at how dorky it looks ;-) .
Direct sunlight will cause an error of 5-10 degrees or more depending on the
color of the sensor and how completely you stop -- this might be remedied by
a shade of some sort to deflect the sunlight.  Can't help much with wet, which
would cause a moderate error in the other direction (from evaporative cooling
of the water) but the sensor would probably stay cooler if mounted high (call
it a creative hood ornament ...)

hope this helps..
                      
<BGB>
lihan@ccwf.cc.utexas.edu        /   The only reason the world hasn't
(really Bruce Bostwick)        /   dissolved into total chaos is that
from the great state of TEXAS /   Murphy's Law also applies to Murphy.
Newsgroups: sci.electronics
From: dan@netcom.com (Dan Liddell)
Subject: flux gate compass damage
Keywords: oops, sorry, degauss?
Organization: Netcom - Online Communication Services  (408 241-9760 guest) 
Date: Mon, 11 Jan 1993 20:30:04 GMT


While torturing a flux gate compass kit with a REALLY strong magnet
(within 1 or 2 inches of the Dinsmore fluxgate device), I managed to
change its idea of north to east (it points east now). 

I could have magnetized ferrous parts on the pc board and in the case
of the battery, but is there any other way I could have damaged the
flux gate device? Does it have a bias field that it must maintain that
I could have buggered with a very strong field?

I do read this group, so post or mail, depending on your extroversion
quotient. thanks.

-- 
Dan Liddell   dan@netcom.com
From: albrecht@csd4.csd.uwm.edu (Chad Edward Albrecht)
Newsgroups: sci.electronics
Subject: Ultrasonic Trans/Recv
Date: 5 Jan 1993 15:44:16 GMT
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4


A few weeks back I posted an article regarding the best type of Elec-Mag Rad
to use for measuring the distance to an moving object.  I wanted to be able
to use triangulation to figure out the exact 3D location of the transmiter.

After review of all your responses I have determined that the most effective
(and cheapest) way to produce these results is to use ultrasonics.  So, my
new questions are these:

	1)  Where can I purchase a relatively cheap and accurate ultrasonic
	    transmitter/reciever set? (Phone #, Addresses)

	2)  Can I get a Receiver(1) to receive more than one frequency at
	    once?  Say for example:
							)--TRANS #1
							)--TRANS #2
			RECV --(		        )--TRANS #3
							)--TRANS #4
							)--TRANS #5
							)--TRANS #6

	   Where each transmitter (1-6) is on it own frequency.

	3)  If I cannot receive these signals simutaneously, then can I
	    receive them in a sequence of say .25 second as such:

	
	SIGNAL			RECEIVED (HIGH)
	------		----------------------------------

	  1		__||______________________________
	  2		_____||___________________________
	  3		________||________________________
	  4		___________||_____________________
   	  5		______________||__________________
 	  6		_________________||_______________


Thanks in Advance!!!!!!

--
>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>><<>>
|  Respond to any of these adresses:    |  "Oh Lord...Ooooh you are so big..,|
|  --------------------------------	| So absolutely huge.  So ab - sol-  |
|  albrecht@csd4.csd.uwm.edu            | utely huge.  Gosh, we're all really|
|  albrecht@convex.csd.uwm.edu		| impressed down here I can tell you!|
|  acct146@carroll1.cc.edu		| --Monty Python: The Meaning of Life|
|============================================================================|
|  UWM-CSD UNIX/MICRO CONSULTANT  Phn# (414) 229-5370 [standard disclaimer]  | 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From: rwc@ius4.ius.cs.cmu.edu (Randy Casciola)
Newsgroups: sci.electronics
Subject: Those Anti-Static Mats
Date: 11 Jan 93 00:25:16 GMT
Article-I.D.: cs.C0nyI5.MG2.2
Organization: CMU Vision and Autonomous Systems


I just bought one of those cheap anti-static mats at a computer
store, one of the ones designed for you to place your computer 
equipment on so that you can touch it to dissipate any static 
before you touch your equipment.  I don't want to use this for
my computer, but for electronics work.  I wanted to test it
somehow, and the only way I could think of was with an DVM.  I
assumed that it would be somewhat conductive.  Well, when I held
the leads against the mat and pressed firmly at a distance of 
about 1 cm, the resistance was greater than the highest range on
the DVM ( >20M ohms).  And the resistance from one end of the
ground cord to the other was about 1M ohm.  I assume they have
a 1M ohm resistor in series somewhere.  But my question is, if
the resistance of the mat is so high, how can it dissipate the
static?  I can buy the fact of it dissipating through 1M ohm or
so, but this mat seems like an insulator.  I measured the 
resistance of another more expensive mat (the type designed to
be placed on the floor for you to walk on) and at 25 cm of 
distance between the leads I measured about 20k ohms.  This
seems more reasonable to me.  Did I get ripped off with mine? 
Will mine still work?

Thanks,

Randy Casciola
Research Engineer
The Robotics Institute
Carnegie Mellon
Pittsburgh, Pa 15213
randy@cmu.edu
Newsgroups: sci.electronics
From: danr@ais.org (Daniel Romanchik)
Subject: Re: Ancient Scope Info Required! (Tektronix Type 564)
Organization: UMCC
Date: Wed, 6 Jan 1993 02:03:01 GMT

In article <1993Jan5.160943.16390@bnr.uk> michthom@bnr.ca (Michael Thomson) writes:
>I am looking for _ANY_ info on the care and feeding of the old Tektronix
>scopes. I recently aquired a 20 MHz dual trace storage scope, but the
>calibration is miles out, and the switches need attention. The scope has
>plug-in timebase and amplifier modules as listed below.
>
>Oscilloscope		Type 564 
>
>Timebase		Type 2B67 \ Plug-in modules
>Dual trace amplifier	Type 3A72 / 
>

You might want to get the book, _Oscilloscopes: Selecting and
Restoring a Classic_ by Stan Griffiths.  There are a couple of
chapters on basic restoring information, then a bunch of info on
classic Tek scopes, and finally a list of parts sources.  The book is
available directly from Stan at 18955 SW Blanton, Aloha, OR 97007.
Stan is now retired, but spent more than 30 years working with Tek
scopes, both at Tek and other places.

Have fun, Dan
=====================================================================
        Dan Romanchik              |        danr@umcc.ais.org
       Technical Editor            |         (313) 930-6564
    Test & Measurement World       |     MCI Mail: tmwromanchik
=====================================================================
Xref: sparky sci.electronics:21958 sci.med:23429 sci.engr.biomed:665
From: ksg@engr.latech.edu (Kenneth S. Guillory)
Newsgroups: sci.electronics,sci.med,sci.engr.biomed
Subject: Need EEG signal processing references
Keywords: EEG
Date: 5 Jan 93 00:16:55 GMT
Reply-To: ksg@engr.latech.edu
Organization: Louisiana Tech University

Greetings,

	About a year ago, I saw a tabloid TV news program that
was showing research being done in EEG signal processing.  In
the clip, they showed a fellow who was controlling ( in real
time ) a stationary model plane's movements through an EEG
interface.  I also saw, in one of my younger sister's 3-2-1
Contact magazines, an article briefly describing how the govern-
ment was conducting research using EEGs ( refered to as "brain
waves" in the article ) to handle some of their fighter plane
control systems.
	I would like to know if anyone knows where this kind of
research ( EEGs used for control systems ) is actually being 
done, and if anyone has seen any journal articles or references
that give more detailed descriptions.  Because I am cross-
posting, please email any responses directly to me, and I'll
post the responses if there are a significant number.

Thanks in advance,

Shane Guillory                  Louisiana Tech University
ksg@engr.latech.edu        Department of Biomedical Engineering
Newsgroups: sci.electronics
From: anto@sol.acs.unt.edu (Anto Prijosoesilo)
Subject: SN75176 pinout needed
Keywords: 75176 pinout
Organization: University of North Texas
Date: Thu, 7 Jan 1993 03:21:19 GMT

Hi netters,

Can anybody tell me 75176's pinout? I can't find it in any of the databooks 
I have access to. 1990 IC Masters lists it as a bidirectional transceiver
mfg. by TI and NS. I don't have access to a recent TI or NS databooks so I'd
appreciate very much if anybody can give me the info.

E-mail preferred to reduce traffic, although I'll also get it if you post
it here.

Thanks very much in advance.

Anto.

Newsgroups: sci.electronics
From: danube@max.physics.sunysb.edu
Subject: Thermocouple based temperature controller
Organization: Institute for the Theoretical Physics
Date: Fri, 8 Jan 1993 03:46:18 GMT


   Hello folks.  I am wondering if someone can offer advice on 
thermocouples.
   I need to control the temperature of a small infrared window to 
0.1 degrees C or better.  The actual value need not be so precise, but
changes in temperature must be kept to a minumum.  At present, the
window is heated by a ring of brass wrapped with heater wire. Adjusting
the current changes the temperature, which is typically 100-200 C.
The temperature is measured with a thermocouple (5 mil Chromel-Alumel wire,
"type K").  Heater current is about 200 mA.
   I would like to build a simple analog circuit to better regulate the 
temperature and be able to easily adjust the set-point.  I envision an
op-amp to amplify the 4mV of the TC to about 1.00 V at 100 C.  Another
op-amp can compare the output to a 0-2V reference voltage and provide
an error output to run a current stage that drives the heater.  I can
read the output of the first op amp on a DVM to obtain a temperature.
The size (and heat capacity) of the window is fairly small and the 
sample (on the window) is fairly heat sensitive, so the stability
must be good (can't quote a spec here, I really don't know).
   Less important, but also desireable, might be a temperature compensation
scheme, since the "room temperature" in this building can vary from 10 C
to 40 C ("Room temperature physics" takes on a whole new meaning here
at Stony Brook).  Also, I could conceivably increase the sample temp. 
up to 600 C, so a way of linearizing the TC might prove useful.
   If anybody has existing circuits for this purpose they are willing
to share, I'd love to see it.  Simple is best, since the simpler it is,
the faster I can build it.  If not, any advice on the best op-amps to
use would also be helpful.
   Finally, though TC's are prefered, I can also use a silicon diode
to measure temp (though not to 600 C).  A similar circuit for a diode
would also be welcome as I have some nicely calibrated 1N914's.  
   Thanks for the help.
							Danube
							(Daniel Koller)
Newsgroups: sci.electronics
Newsgroups: sci.electronics

bob@kc2wz.bubble.org (Bob Billson) writes:

>I need a couple (9 to be precise) of 450 mAH nicads.  Problem is they need
>to be N cells.  Radio Shack sells N size nicads but they are only 150 mAH.

Good luck.  This sounds like an unrealistic expectation for capacity in
an N cell.  You might get 200mAH in a high capacity one.

Try the battery-replacement places that advertise in the ham magazines,
like Yost and ...  can't remember the other right now.  Check QST etc.
Most of the places have 1-800 numbers.