HDTenEightyP/NetNews huggingface dataset:
Newsgroups: sci.electronics

> Yes, just taking the signal to the sync level (0v) for a couple of line
> periods will do it. Its crude, but is done on many of the cheap
> computers & TV games.
> 

Slight correction needed here: the sync level of the "NTSC" video signal
ISN'T 0V.  The video signal standards (in this case, the relevant one is
EIA standard RS-170) assume that the monitor will use AC coupling for the
input signal, and therefore an absolute definition for these levels isn't
provided.  For the RS-170 signal, the sync tips are down 0.4V from the 
reference level, which is always assumed to be the "blank" (NOT black) level.
For RS-343 (the other common standard, used extensively in computer displays),
the corresponding number is 0.286V down from blank.

Quite often, computer video outputs will "build the signal" up from 0V, which
puts the sync tips at this level.  However, this ISN'T a universal practice.
Some video DACs - especially those running at high rates, and therefore likely
to use ECL inputs and supplies - actually "build" the signal DOWN, which puts
the "white" level at 0V (or thereabouts - it's all the same to the monitor,
as long as the peak-to-peak remains the same and the timing's right).


Bob Myers  KC0EW   Hewlett-Packard Co.      |Opinions expressed here are not
                   User Interface Tech. Div.|those of my employer or any other
myers@fc.hp.com    Fort Collins, Colorado   |sentient life-form on this planet.
Newsgroups: sci.electronics
From: wrb@cbnews.cb.att.com (wallace.r.blackburn)
Subject: Re: CSMA/CD on RS232?
Organization: AT&T
Distribution: usa
Date: Tue, 15 Sep 1992 15:33:42 GMT

In article <1992Sep15.150015.7409@sbctri.sbc.com> tadams@sbctri.sbc.com (Tom. Adams 529-7860) writes:
>I was wasting time in a meeting, and came up with an idea that seems
>interesting to me.  Consequently I'm sure it's been done, or more likely
>been shown to be just incredibly stupid. :)
>
>I'd like to connect multiple devices to an RS232 line, buswise.  All devices
>would either be programable, (i.e. PC's) or be frontended by a (cheap)
>microprocessor.  I'm wondering if CSMA/CD is a reasonable way to manage 
>very low speed bus contention.  If so, it would seem reasonable to transmit 
>address information, data, CRC's etc over the wire.  I'm not quite sure
>how to manage the Collision detect part, since I can't just look at 
>voltage levels on the wire.  Applications would be low volume data logging
>and control systems, ridiculously overpriced burglar alarms, etc.
>
Icom uses this system with their computer-controllable amateur radio
transceivers and general-coverage receivers.  They call it their CI-V
system.  Each type of radio has a different default address (which can be
changed).  This way, you can connect multiple radios to one computer and
control them independently.  They do TTL out of the back of the radio, so a
level converter is also needed.  This is how I became interested in this, I
have an article on radio-computer interfacing coming out in 1/93 QST.

My new Ten-Tec Omni VI has the same system.  I'm running it at 19.2K, but
only have the one radio hooked up.

To check for collision, just listen to what you transmit.  If you don't hear
the same thing you sent then there was a collision.  Good luck.


			Wally Blackburn AA8DX
			wrb@ccsitn.att.com
Xref: sparky sci.electronics:15518 rec.video:11174
From: perl@dwrsun4.UUCP (Robert Perlberg)
Newsgroups: sci.electronics,rec.video
Subject: Re: Macrovision
Date: 11 Sep 92 18:10:01 GMT
Organization: Dean Witter Reynolds Inc., New York

In article <1992Sep2.133450.18671@panix.com>, schuster@panix.com (Michael Schuster) writes:
> Macrovision inserts very bright pulses in the vertical blank interval.
> Most VCR's use this when setting AGC video level, and get fooled into
> thinking the video levle is much brighter than the picture area really
> is. Most TV's don't. Dunno why.

Some years ago a VCR maker (forgot which one) came out with a machine
which used a different kind of AGC circuit which was not affected by
Macrovision.  It was not their intention to defeat Macrovision, it just
worked out that way because Macrovision takes advantage of an
unintended behavioral characteristic of the extant AGC circuit.  The
Macrovision people complained and the VCR maker modified the new
circuit so that it would reject a Macrovision signal.

Robert Perlberg
Dean Witter Reynolds Inc., New York
{murphy | philabs}!dwrsun4!perl
	-- "I am not a language ... I am a free man!"
From: bender@oobleck (Duke of Canterbury)
Newsgroups: sci.electronics
Subject: Re: NEED: TTL controlled 115V 5A Switching
Date: 10 Sep 1992 06:06:50 GMT
Organization: SPARK's R US
Reply-To: bender@oobleck.eng.sun.com
NNTP-Posting-Host: oobleck
X-Newsreader: Tin 1.1 PL3

jg3o+@andrew.cmu.edu (Jason Ari Goldstein) writes:
: Hey now,
: 
: The subject pretty much says it all.  I need to switch some light
: switches with TTL signals (I am building a controller for my
: fraternities dance floor lights).  Basically, I have heard you can use
: relays, triacs, etc.  Unfortunately, no one seems to have a circuit
: design to show me.  I would like to use triacs because they are
: non-mechanical and less likely to blow than relays.

I've found that Triacs make a better fuse than a fuse if one of your
lighting circuits happens to short, and Triacs usually fail in the
ON (or shorted) state, so once you fix the short, replace the fuse
(you DO have a fuse, right?) and power on again, you'll find that your
light is on all the time.

: I have seen some
: circuits for using triacs but NONE that showed how I can use TTL logic
: to do the switching.

If you happen to swing by a Radio Shack, pick up their large yellow
book on electronics projects by Forest Mimms III; I believe that there
is an example circuit in there using a triac and an opto-isolator to
make an inexpensive solid-state relay.

mike
Xref: sparky sci.electronics:15257 rec.radio.amateur.policy:1581 alt.folklore.urban:22902
From: mcovingt@athena.cs.uga.edu (Michael A. Covington)
Newsgroups: sci.electronics,rec.radio.amateur.policy,alt.folklore.urban
Subject: Is this legislation for real?
Date: 5 Sep 92 04:45:04 GMT
Distribution: usa
Organization: University of Georgia, Athens

I have been told that the following 2 things are before the Senate, but
cannot locate them in Congressional Record and similar sources.  Can
anyone elucidate?

(1) A bill to abolish private consulting, "Senate 1706", mentioned by
a correspondent to Robert Pease in a recent issue of _Electronic Design_.
(There _is_ a Senate 1706, but it has to do with import duties on some
industrial chemicals.)

(2) A bill to ban receivers that can tune in cellular phones.
(Right now, eavesdropping is illegal but the equipment itself isn't.)

-- 
+ Michael Covington - Artificial Intelligence Programs - U of Georgia - USA 
+ Unless otherwise noted, these are private opinions, not official statements.
+ VOTE NO GEORGIA LOTTERY - we need not imitate mistakes of other states.
Newsgroups: sci.electronics
From: mat@mole-end.matawan.nj.us
Subject: Wanted: waterfall/fountain noise
Organization: :
Date: Fri, 11 Sep 1992 00:48:50 GMT

I hope this wasn't covered six months ago ... but:

Does anyone have a not-too-complicated (read: parts cheaper than buying
a commercial box) `noise' device that approximates the sound of water
pouring over a `fountain'?  Not the sound of a few parabolic streams,
but of water falling over/around obstacles and falling a considerable
distance into a body of water.
-- 
 (This man's opinions are his own.)
 From mole-end				Mark Terribile

 mat@mole-end.matawan.nj.us, Somewhere in Matawan, NJ
From: neal@cmptrc.lonestar.org (Neal Howard)
Newsgroups: sci.electronics
Subject: Re: A much better power inverter design
Date: 11 Sep 92 21:40:34 GMT
Organization: CompuTrac Inc., Richardson TX

>Dynamoters...you forgot the true dinosaurs of High Voltage.  The proper
>technique when using dynamotor powered ARC-5 transmitters was to press
>the mike key and wait a second or so until the motor was up to speed.
>It really brings back memories of adding another battery to the car's
>electrical system to bring the voltage up to 24 volts for the dynamoters.
>--
>Larry                                   |   Thunder makes all the noise;

You sure know how to make a guy feel old!!! And I'm only 30 !!!
I remember playing with these as kid growing up in my dad's TV/2way radio
repair shop. He used to get them from army surplus places and old retired
police radios. The old cop car units were neat since they would run off
12V and provide about 400v for b+ for making homemade 50watt RF amps 
for two way radios (no comment on what meter band these were tuned to :-)
I think they were made by either GE or Motorola and I think my dad may
even have one or two of these old dynamotors in the junk pile. When the
mike was keyed, you could even hear the 400Hz whine at the receiving end
since large electrolytic filter caps were at premium back then and difficult
to get in small towns.

Ahhh, the good old days.
=======================================================================
= Neal Howard                         | '91 Harley Sportster XLH-1200 =
= email: neal@cmptrc.lonestar.org     | DoD # 686                     =
= CompuTrac, Inc. (Richardson, TX)    | '69 Cougar XR7-GT390          =
=======================================================================
From: uni@acs.bu.edu (Shaen Bernhardt)
Newsgroups: sci.electronics
Subject: Wanted
Date: 12 Sep 92 01:26:14 GMT
Distribution: h
Organization: Boston University, Boston, MA, USA


Newsgroups: sci.electronics,comp.robotics
From: kowal@stsci.edu (Charles Kowal)
Subject: AY5-8116 BRG pinouts
Followup-To: poster
Organization: Space Telescope Science Institute
Date: Wed, 16 Sep 1992 01:01:49 GMT

 Can anyone please send me a list of the pinouts for an AY5-8116
 Baud Rate Generator?  I believe this part is made by General
 Instruments.
 Actually, all I really need are the locations of Vcc and Vss.
 It would also be very helpful to know how to set the baud rate!

 Many thanks.

                                       Charles Kowal
                                       kowal@stsci.edu
From: mcovingt@athena.cs.uga.edu (Michael A. Covington)
Newsgroups: sci.electronics
Subject: Cassette recorder questions
Date: 9 Sep 92 02:12:29 GMT
Article-I.D.: athena.1992Sep9.021229.20646
Distribution: usa
Organization: University of Georgia, Athens

(1) Are the counters on cassette tape recorders standardized?
That is, do they all read the same numbers for the same positions?

(2) Where can I get a test tape for adjusting alignment and speed?
Minimally, it should have a tone at a known frequency recorded on it.



-- 
+ Michael Covington - Artificial Intelligence Programs - U of Georgia - USA 
+ Unless otherwise noted, these are private opinions, not official statements.
+ VOTE NO GEORGIA LOTTERY - we need not imitate mistakes of other states.
From: ghw@brahms.udel.edu (George Watson)
Newsgroups: sci.electronics
Subject: Re: Question about origin of name of BNC connector
Date: 9 Sep 92 02:57:27 GMT
Organization: University of Delaware

In article <BuA81s.6pp@scd.hp.com> albert@PROBLEM_WITH_INEWS_GATEWAY_FILE (Albert Alcorn) writes:
>lmbrown@vela.acs.oakland.edu (lmbrown) writes:
>: I think that the BNC stands for Bayonet Connector.  Can anyone confirm or
>: disprove this?
>: 
>: 
>The one I heard was:
>
>Bayonet Navy Connector
>
And certainly not the ``baby N'' connector as stated by
Horowitz and Hill, pg 55! (A rare glitch in an excellent text.)


-- 
George Watson                  | 
Dept. of Physics & Astronomy   |   Gosh darn the torpedos,
University of Delaware         |     full speed ahead!
ghw@brahms.udel.edu            |
From: strong@tc.fluke.COM (Norm Strong)
Newsgroups: sci.electronics
Subject: Re: Question about origin of name of BNC connector
Date: 14 Sep 92 14:37:19 GMT
Article-I.D.: tc.1992Sep14.143719.21914
Organization: John Fluke Mfg. Co., Inc., Everett, WA

In article <BuAIvr.Jzy@news.udel.edu> ghw@brahms.udel.edu (George Watson) writes:
}In article <BuA81s.6pp@scd.hp.com> albert@PROBLEM_WITH_INEWS_GATEWAY_FILE (Albert Alcorn) writes:
}>lmbrown@vela.acs.oakland.edu (lmbrown) writes:
}>: I think that the BNC stands for Bayonet Connector.  Can anyone confirm or
}>: disprove this?
}>: 
}>: 
}>The one I heard was:
}>
}>Bayonet Navy Connector
}>
}And certainly not the ``baby N'' connector as stated by
}Horowitz and Hill, pg 55! (A rare glitch in an excellent text.)

I called up the President of Pasternak Enterprises, a company that makes
its living manufacturing these things, and he said it meant:

Bayonet Navy Connector

TNC means Threaded Navy Connector.  

Judge for yourself.  

-- 

Norm Strong  (strong@tc.fluke.com)
2528 31st S.   Seattle WA 98144   USA
Newsgroups: sci.electronics
From: etxansk@garbo.ericsson.se
Subject: Where does snow come from?
Originator: etxansk@garbod20
Organization: Ericsson
Date: Tue, 8 Sep 1992 10:01:08 GMT


 I'm wondering where the snowy screen information comes from, on a TV
set that isn't receiving any real RF video signal.

 Is the snow "in the air" or does it only exist in the TV's tuner?

 If it's noise from earth and the rest of our universe, will this
messy information fade away if I hide the tuner's receiving parts
behind a shield that's good enough?

 I don't need the answer to solve a specific problem, I'm just 
curious about how these things work.

 Anders Skelander
 
Newsgroups: sci.electronics,rec.radio.amateur.policy,alt.folklore.urban
From: eric@telebit.com (Eric Smith)
Subject: Re: Is this legislation for real?
Organization: Telebit Corporation
Distribution: usa
Date: 6 Sep 92 17:10:03

>>On 5 Sep 92 04:45:04 GMT, mcovingt@athena.cs.uga.edu (Michael A. Covington) said:
> (2) A bill to ban receivers that can tune in cellular phones.
> (Right now, eavesdropping is illegal but the equipment itself isn't.)

Geez, you mean old televisions with UHF tuners will become illegal?  :-)
Newsgroups: sci.electronics,comp.sys.intel
From: wright@lims01.lerc.nasa.gov (Ted Wright)
Subject: Re: Info needed on 16MByte SIMMs for PC
Organization: NASA Lewis Research Center
Date: Mon, 14 Sep 1992 20:03:32 GMT

In article <BuDJsw.8t1@unx.sas.com> sasbge@ant.unx.sas.com (Gantt Edmiston) writes:
>From: sasbge@ant.unx.sas.com (Gantt Edmiston)
>Subject: Info needed on 16MByte SIMMs for PC
>Date: Thu, 10 Sep 1992 18:10:07 GMT

>I'm considering the purchase of a 486DX2 66MHz PC.  The seller (Gateway 2000)
>advertises that these systems are capable of being configured with a 
>maximum of 64MBytes of main DRAM memory.  Investigation has shown that
>their motherboards have four SIMM slots.  Currently, Gateway does not offer
>the 16MByte SIMMs.  In fact, their sales rep sez that they only have the
>4MByte SIMMs so if I *did* purchase from them, I could currently only
>get a maximum of 16MBytes (four slots X 4MByte SIMM) total configured
>at this time.
>
> .......some stuff deleted
>
>-----------------------------------------------------------------------------
>Gantt Edmiston - SysAdmin       |If you always do what you have always done, 
>SAS Institute Inc.              |you'll always get what you've always gotten!
>Quality Assurance - V416        +--------------------------------------------
>Cary NC 27513 919-677-8000 x6091|          sasbge@ant.unx.sas.com
>-----------------------------------------------------------------------------

My Gateway 486/33E is advertised as accepting up to 64Meg of DRAM, but
it has 8 SIMM sockets. Perhaps the Gateway saleperson is confused.

Note that my computer came with 8 Megs in 4 SIMMs, these turned out to be
512K by 36 bit SIMM modules, not the 2Meg by 9 modules that I expected.
Ted Wright (wright@lims01.lerc.nasa.gov)

Newsgroups: sci.electronics
From: sakaria@vipunen.hut.fi (Sakari Aaltonen)
Subject: Re: What Steve Wants
Reply-To: sakaria@vipunen.hut.fi (Sakari Aaltonen)
Organization: Helsinki University of Technology
Date: Mon, 14 Sep 1992 15:09:18 GMT

In article <1992Sep14.013048.263@ssc.wa.com> markz@ssc.wa.com (Mark Zenier) writes:
>......................................
>Are there any other good european electronics magazines?
>......................................

"c't" and "mc" are my staple. They are German; for some reason, they insist
on lowercase titles.
They are really computer magazines, but they have interesting hardware
projects, too, like Byte used to in the Ciarcia days. By the way, does
anyone know why Ciarcia left Byte? I liked his articles. Well, his superior
tone did grate on my nerves....:-)
-- 
-----------------------------------------------------------------------------
Sakari Aaltonen                             Helsinki University of Technology
Email: sakaria@vipunen.hut.fi
---  You can't keep a Finn down without him getting all red in the face  ----
Newsgroups: sci.electronics
From: pngai@adobe.com (Phil Ngai)
Subject: Re: GAL LOGIC
Organization: Adobe Systems Incorporated
Date: Wed, 9 Sep 1992 20:04:58 GMT

Would you program an Intel EPROM with a Toshiba algorithm?
What if Toshiba had trademarked "EPROM", would that make
any difference?

What's your definition of GAL anyway?

-- 
My opinions are my own.
Vote for Clinton: protect the right to keep and bear sporting goods.
From: stettbac@isibee14 (Juerg Stettbacher)
Newsgroups: sci.electronics
Subject: Real time clock with DSP56000
Date: 9 Sep 92 17:04:06 GMT
Organization: Swiss Federal Institute of Technology (ETH), Zurich, CH
X-Newsreader: Tin 1.1 PL5


Hello world

I try to add a real time clock to my DSP56000/1 system. I prefer
a parallel interface.

Does anyone know about a chip, that interfaces easily with the
DSP56000/1 bus?


Thanks for help
juerg at ethz switzerland
Newsgroups: sci.electronics
From: tidedu@mars.lerc.nasa.gov (William T. Dedula)
Subject: How to drive 1 or 2 segments (ONLY) of a Liquid Crystal Display ?
News-Software: VAX/VMS VNEWS 1.41    
Organization: NASA Lewis Research Center
Distribution: usa
Date: 10 Sep 1992 10:34 EDT  

Hello All;
I am building a project which requires a LCD counter. I am using 
MM74HC4543's to drive each of the 4 digit's BUT I need to drive 
a few special indicators on the LCD panel such as a LOW BATT 
indicator. I'd like to know how I can do this ? Would the normal
proceedure be to use another MM74HC4543 or is there a simpler way ?

Thank You very much for your response !!!

Tim 

W. Tim Dedula                        Internet: 
N.A.S.A. Lewis Research Center       tdedula@nasamail.nasa.gov
Mail Stop 77-3                       tidedu@mars.lerc.nasa.gov
21000 BrookPark Road                 aa252@cleveland.freenet.edu
Cleveland, Ohio 44135
Phone (216) 433-3668

The National Aeronautics and Space Administration: Science and
Technology ... for the Benefit of ALL Mankind !!!

Newsgroups: sci.electronics
From: rubin@glockenspiel.cis.ohio-state.edu (Daniel Rubin)
Subject: Re: NEED: TTL controlled 115V 5A Switching
Organization: The Ohio State University Dept. of Computer and Info. Science
Date: Sun, 13 Sep 1992 16:39:49 GMT

>>fraternities dance floor lights).
>>BTW, I have looked into solid state relays but $17-$25 each is way too
>>much.  So, if someone could send me a circuit diagram or point me to a
>>good book (especially for triacs) it would make me very happy.
>
>They're cheaper surplus; Hosfelt Electronics (1-800-524-6464) has a 10A
>opto-isolated solid state relay for $9.95, and an optoisolated 2.5A relay
>for $2.59 (which could be used to switch individual lights).  They have no

You can make them yourself even cheaper...  There is an article in a recent
issue of Radio Electronics that gives about a dozen different circuits for
solid state relays and the like.  Look in your library for solid state relay
related articles and I am sure this article will pop up.  The basic circuit
is quite simple and sould not cost more that $2 depending, of course, on the 
current rating of the Triac used.

If you can't find the article let me know and I will try to remember to look
for that issue of Radio Electronics when I am at home...

								- Dan
-- 
  Daniel Joseph Rubin    |  "...A good football team for the alumni, parking
rubin@cis.ohio-state.edu |  for the faculty and sex for the students."
      GO        GO       |  - President E. Gordon Gee on the three things that
    BENGALS  BUCKEYES    |  a great university president must provide.....
Newsgroups: sci.electronics
From: hbg6@phx.mcd.mot.com (John Schuch)
Subject: LCD applications wanted
Organization: Motorola Computer Group, Tempe, Az.
Distribution: usa
Date: Mon, 14 Sep 1992 16:48:48 GMT

I developed a simple cable and driver system to connect a two line
by 40 character LCD module to the parallel port of my PC. I needed
it to test about 40 LCD modules I bought at a 'junk' store and it
worked very well.

A couple of people suggested I publish the thing but I can not think
of any good applications for driving an LCDM from a PC other than
testing the module.

Can you think of any good uses for this thing?

Thanks, John
From: root@drdhh.hanse.de (Bjoern Kriews)
Newsgroups: sci.electronics
Subject: Re: RS-232 Line Monitor/MAX 233???
Date: 9 Sep 92 16:06:20 GMT
Organization: Digital Island

geb1@ra.msstate.edu (Granville Barker) writes:
>I have never used a max 233 do they require any caps/ wierd voltages?
>Can they get power from the 232 port?

233 is the capless version of the std max232.
Just requires 5V.
You could try to get power from DTR or something the like, but I wouldn't
recommend it.

-- 
bkr@drdhh.hanse.de - Bjoern Kriews - Stormsweg 6 - D-2000 Hamburg 76 - FRG
------------------------------------------------------------------------------
         "Ich trinke auch nicht weniger als andere Leute."  (K.H.)
From: mgm@world.std.com (michael g moncur)
Newsgroups: sci.electronics
Subject: Re: LCD displays, again
Date: 15 Sep 92 05:31:56 GMT
Organization: The World Public Access UNIX, Brookline, MA


Another source for *incredibly* cheap LCD displays:  Marlin P. Jones and
Co., a discount catalog place in FL.  Here's a sampling:

16 char X 1 line - backlit? not sure. - $7.95 
20 char X 2 line - backlit, inverter not inq., $15.00 
256X64 dot matrix - backlit, inverter not inq., $16.00
640X200 dot matrix - backlit? , $29.95
640X400 (!) dot matrix - backlit, no inverter, $55.00.  Compare $550 at
Newark electronics...  I bought one of these.  Havent figured out the
bizarre interface yet, though. 
480X128 dot matrix - not sure if backlit - $19.95
 

and a few others...  Excellent prices.  They also have some amazing prices
on solderless breadboards.  Call for a free copy of their (cheaply
produced) catalog. 
 
 Marlin P. Jones & Co. 
(407) 848-8236 
PO Box 12685
Lake Park, FL 33403-0685 
 
(note: i am not affiliated with that company in any way - i just thought
some people might want to know about this.)
 
 Michael Moncur - mgm@world.std.com
From: carmijo@hpnmdla.sr.hp.com (Chris Armijo)
Date: Fri, 11 Sep 1992 17:20:51 GMT
Subject: Re: Impedance match 50 to 75 ohms
Organization: Hewlett-Packard, Santa Rosa, CA