HDTenEightyP/NetNews huggingface dataset:
From: jgd@dixie.com (John De Armond)
Subject: Re: How are neon tubes made?
Date: Tue, 17 Nov 92 18:11:33 GMT
Organization: Dixie Communications Public Access.  The Mouth of the South.
Distribution: usa

jsevinsk@digi.lonestar.org (John Sevinsky) writes:

>I've been thinking about the idea of making my own neon tubes, and I have no
>idea what's involved with filling the tube with neon.  Does anybody know what
>kind of equipment is needed and how much it would cost?

You'll need a high vacuum pumping system.  Either a rotary pump and a 
diffusion pump or a turbomolecular pump.  Either costs in the thousands
new.  I saw a rotary/diffusion setup at a hamfest recently for $75
and was foolish enough not to buy it.  You'll next need a high vacuum
gauging system. Figure a grand for an ion gauge.  Sign grade neon and
argon are kinda expensive but the cylinders it comes in are even 
worse.  Figure at least $20 a month demurrage for each.  Then you'll
need the high purity regulators at about $200 each plus misc 
piping and valving.  Figure another grand for that.

That said, I'll observe that one CAN get in a lot cheaper if one is not
terribly worried about the quality or longevity of the tubes. I've
seen some pretty atrocious setups in shops I've sold gas to.  Rubber
hoses, ordinary plumbing valves and so on.  The problem is if 
large molecules are permitted in the system, they cause rapid electrode
sputtering which drastically lowers tube life.

It is a lot of fun, though.  I used to have a setup similar to what I
describe above, assembled from surplus parts.  I used it to make 
homemade lasers.  Some even worked :-)

73 John

-- 
John De Armond, WD4OQC               |Interested in high performance mobility?  
Performance Engineering Magazine (TM) |
Marietta, Ga                         |Interested in high tech and computers? 
jgd@dixie.com                        |Write me about PE Magazine
Need Usenet public Access in Atlanta?  Write Me for info on Dixie.com.
Newsgroups: sci.electronics
From: s35130w@kaira.hut.fi (Tom Mikael Ahola)
Subject: Digital Audio Interfaces: S/PDIF, AES/EBU and Alesis ADAT!
Summary: Info on Digital Audio Interfaces (Wanted)
Keywords: S/PDIF, AES/EBU, ADAT, Digital Audio
Organization: Helsinki University of Technology, Finland
Date: Mon, 23 Nov 1992 07:36:15 GMT

Hello everybody!

I'm planning to build some fancy digital audio equipment and
would like to use the optical digital output from the Alesis
ADAT. This output carries 8 audio channels on one optic fiber
and is probably not standardized.  I probably have to call
Alesis for any info on the format used but I also would like to
hear comments from anyone on the net who has info/experience
about this interface. Could I perhaps use S/PDIF chips running
at 8x speed to decode the format?

I'm also interested in the S/PDIF and AES/EBU formats. I don't
like to pay lots of $$$$$ to buy a thick book with a couple
of useful sides with the formats explained - so I use the scope.
This is what I discovered by monitoring the S/PDIF output with
an o-scope:

   Sample rate:           44100 Hz
   Frames/sample:             2         (left frame, right frame)
   Bits/frame:               32         (64 bits per sample)
   Bit rate:          2 822 400 bits/sec
   Transmission coding:   Bi-Phase Mark (Harvard-FM)

Frame format:

  left frame:  0101 0000 0000 xxxx xxxx xxxx xxxx ab0c
  right frame: 0110 0000 0000 xxxx xxxx xxxx xxxx ab0c

                x = audio data bits,  16 bits/frame
                a = changes 1/0 in pause mode
                b = changes 1/0 always
                c = checksum bit (restores signal level to zero)

The first four bits are obviously some kind of frame synchronization
bits and are coded differently from the other (without bit clock?
NRZ-FM). There seems to bee 8 extra (subcode) bits in a frame!

I would like to know what the functions of bits a and b are. Has
the b-bit something to do with SCMS?

Mail me corrections and more info if you have it and I'll summarize
here the complete format specs (or is this a FAQ?).

  Thank You!
  

OoOoooOOooOoOoooooOooooOoooooOOoOooOoOoooOooOooOooOooOOoooOoOoooOoooOooO
+       Tom Ahola     tahola@otax.tky.hut.fi  (128.214.8.1)            +
oOoooOoOoOooooOoOooOoooOoooooOooOooOoooOooOoOooooOoOooOooooOooOoOOOooOoO
From: karol+@pitt.edu (Filip M. Gieszczykiewicz (fmgst+@pitt.edu))
Newsgroups: sci.electronics
Subject: Where to post a one-night project?
Summary: got a 70K zip, Bike-light, etc.
Keywords: here, alt.sources, ?
Date: 16 Nov 92 13:10:34 GMT
Followup-To: sci.electronics
Distribution: usa
Organization: University of Pittsburgh


	PLEASE REPLY TO "fmgst+@pitt.edu" NOT THIS ACCOUNT. THANKS.

	Greetings. The long awaited Super-Bright LED Bike Light
	project is ready for posting. It comes in a 70K PKZIP file
	and I was just wondering if I should post it here. But
	before I waste "hunderds if not thousands" of $, perhaps
	someone would like to give me their opinion on the file.
	If so, e-mail to "fmgst+@pitt.edu" and state that your 
	mail spool won't overflow :-)

	By the way, the ZIP has 8 small GIFs and a few text files.
	Be back in a week or so with the results.

	Take care.
-- 
-------------------------------------------------------------------------------
DO NOT REPLY HERE. REPLY TO "fmgst+@pitt.edu". THANK YOU. If that doesn't work,
send that e-mail to "fmg@alpha.smi.med.pitt.edu". Proud co-owner of a Jeanie's
Teenie serial# 1: all-Al, 285lb, low-wing, 53 hp, 120 knts, experimental plane!!
From: paula@nlbbs.UUCP (Paula Stockholm)
Newsgroups: sci.electronics
Subject: Old phone
Date: Fri, 20 Nov 92 01:37:47 GMT
Reply-To: paula@nlbbs.UUCP
Distribution: world
Organization: The Electronics Workbench


In article <722202917snx@nlbbs.UUCP> paula@nlbbs.UUCP writes:

 > 
 > 
 > In article <1648@airgun.wg.waii.com> miller@hmsp04.wg3.waii.com writes:
 > 
 >  > 
 >  > I have an old telephone (circa 1963, from the dates stamped inside) that >  works
 >  > 
 >  > Surely the wiring has changed since then - I understand that there used to >  be
 >  > 3 wires/line and now there's 2 wires/line. Maybe with a little redirection
 >  > of the internal wiring I can get the ringer to work?
 >  > 
 >  >      Griff,
 > 
 >         You're on the right track - Tip and Ring (red & green) are the
 >         "active" wires in phone lines. Used to be that Sleeve (yellow)
 >         was the ground.
 > 
 >         Older phones sometimes were wired with the bell connected from
 >         Tip-Sleeve or Ring-Sleeve or, on private lines, Tip-Ring.
 > 
 >         You may find that the red and green wires from the phone cord go
 >         to L1 and L2 in your old phone. To work nowdays, there should be
 >         a wire to the bell connected to each of these. If not, look at
 >         where the cord's yellow wire connects. Move the bell connection
 >         from there to the lonesome red or green connection.
 > 
 >         Also there are two other wires from the bell. These should
 >         connect to K and A on the transformer thing (where L1&L2 are).
 >         A capacitor should also be connected to K and A.
 > 
 >         Like this:
 > 
 >              RED L2 ---/\/\/\-- K --||-- A --/\/\/\/\---- L1 GREEN
 >                       1/2 Bell      CAP      1/2 Bell
 >                        Coil                   Coil
 > 
 >         * * * * * * * * * * * * * *  * * * * * * * * * * * * * * *
 >         *   Paula Stockholm              paula@nlbbs.UUCP        *
 >         *  Cumberland, Maine          !nlbbs!paula@uunet.uu.net  *
 >         * * *  * * * * * * * * * * * * * * * * * * * * * * * * *
 >                        
 > 
 > 
 > 
 > 
 > 
 > 
 > 
 > 
 > 
 > 
Newsgroups: sci.electronics
From: phys58@jetson.uh.edu (Hortvet, Douglas Richard)
Subject: COAX CABLE
News-Software: VAX/VMS VNEWS 1.41    
Organization: University of Houston
Distribution: usa
Date: Mon, 9 Nov 1992 23:06:00 GMT

Can someone provide a brief overview of the various applications for the 
different varieties of coax cable. In particular, what cable specifications
are recommended for tv antenna connections, cable tv connections, and other
consumer applications.

Is there a good general reference for electronic component characteristics,
application recommendations, etc?

Any information will be appreciated.

Thanks.
From: ballen@convex.csd.uwm.edu (Bruce Allen)
Newsgroups: sci.electronics
Subject: circuit simulation
Date: 16 Nov 1992 22:53:29 GMT
Organization: Computing Services Division, University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.30

I'd like to do computer simulation of some fairly
simple audio-frequency circuits made of passive
components, diodes, transistors, and op-amps.

Ideally I'd like to be able to draw a schematic on
the screen, supply device parameters, and then simulate
response for various inputs.

This system should run on a SparcStation (Sun-4)
although if I need a Mac or PC I could probably find
one.

Could someone please recommend a public-domain program
that does this?  If not, could you recommend an inexpensive
commercial package?

Cheers,
	Bruce Allen
	PS: please respond to ballen@dirac.phys.uwm.edu

From: pauls@trsvax.tandy.com
Date: 20 Nov 92 11:36 CST
Newsgroups: sci.electronics
Subject: Re: How can a radar detector bedetected
Message-ID: <288200029@trsvax>
Nf-ID: #R:music.mus.polymtl.ca:36:trsvax:288200029:000:187
Nf-From: trsvax.tandy.com!pauls    Nov 20 11:36:00 1992


Wrong.

It has a "local oscillator" which it emmitting RF energy (albeit
low-level). Any sensitive spectrum analyzer will pick it up.

Also, are you sure that they just didn't SEE it??
From: spcecdt@deeptht.armory.com (John DuBois)
Newsgroups: sci.electronics
Subject: Serial-interface EPROM programmer recommendation wanted
Date: 22 Nov 92 04:29:25 GMT
Organization: The Armory


     I'm looking for a (relatively) low cost EPROM programmer.  I want a
serial interface because I run UNIX, and don't want to write a driver,
don't have a free slot, and do have a free port on a multiport board, and
don't want to build a custom cable to reach to my workbench.  Unfortunately
this appears to cut down on my options quite a bit.  The cheapest serial-
interface programmer I've found is one from Jameco for $300.  Are there
better deals out there?  I need to at least be able to program 27* EPROMs.
Microcontrollers, etc., or expandandability in that direction are a plus
but I can live without that capability.
     Also, the Jameco programmer has a 1200bps interface.  My impression
is that this is liable to be a bottleneck, but then the last programmer I
used was a Prolog thing whose interface was a hex keypad (with no buffer
at all... hit the wrong key, put it in the eraser and start over!)  Do the
fast-programming algorithms work faster than 60 writes/second (I think the
serial interface uses hex)?  20 minutes to program a 64K EPROM sounds slow.

	John
-- 
John DuBois	spcecdt@deeptht.armory.com	KC6QKZ
Newsgroups: sci.electronics
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: Secam to Pal
Keywords:  Video
Organization: Macquarie University, Sydney
Date: Thu, 19 Nov 1992 00:59:19 GMT

In article <1992Nov17.161717.2694@acri.fr>, pjhicks@hard03.acri.fr (Peter J. Hicks) writes:
|>  Is there anybody out there that knows how to transcode Secam to Pal ?
|>  
|>  Are there chips available that do this function or is it a matter of building a mass of logic 
|> 
|>  if  so,  hows about a circuit diagram.
|> 
|>   Final question  What is the difference between  Secam and Pal ?
|> 

NTSC	Never Twice the Same Colour
SECAM	Something Essentially Contrary to the American Method
PAL	Practical Alternative to the Losers

But seriously:

The PAL system attempts to overcome the limitations of NTSC colour phase shift by
reversing the phase of the colour subcarrier signal on successive lines. So any
phase distortion tends to average out: one line might be a little too red, while
the next, a little too green. The eye is nowhere near as sensitive to colour
perturbations as it is to brightness, so the whole thing works. PAL also uses
(R-Y) and (B-Y) colour difference signals, rather than the more complex I and Q
chrominance signals of NTSC.

SECAM transmits one colour difference signal during one scan line, and the other
during the succeeding line. The receiver must delay the first difference signal
by one line period, so as to have both available for processing. So, in total,
only half the colour information of the other two systems is available. Hence the
name behind the acronym: syste`m e'lectronique couleur avec me'moire.

Provided you are referring to conversion between two systems with identical line
rates, there is no particular reason why you should not be able to generate PAL
from SECAM, given the caveat of only having half the colour information of a
regular PAL signal. In fact, Philips/Signetics have done it for you in their
TDA3592A SECAM/PAL transcoder chip.

JohnH

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

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

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

----------------------------------------------------------------------------
Organization: University of Maine System
Date: Monday, 16 Nov 1992 15:43:38 EST
From: Robert A. Sobczak <SOBCZAK@MAINE.MAINE.EDU>
Newsgroups: sci.electronics
Subject: WANTED: TI semi

I am looking for a semi-conductor that Texas Instruments built in Signapore
back in 79.

Texas Instruments - TMS 1951N2L

TI no longer supports it and I have tried looking for the company that used it
in this clock, but they seem to no longer be in business. (Kingspoint)

Let me know if I might find this bugger anywhere.

Thanks
Rob

Sobczak@maine.bitnet
Sobczak@maine.maine.edu
From: cstadbg@csv.warwick.ac.uk (Mr M J Brown)
Newsgroups: sci.electronics
Subject: Re: Using big caps as computer power supply filters (?)
Date: 18 Nov 1992 13:28:38 -0000
Organization: Computing Services, University of Warwick, UK
Distribution: world
NNTP-Posting-Host: clover.csv.warwick.ac.uk

In article <1992Nov17.115412.26749@doug.cae.wisc.edu> kolstad@cae.wisc.edu (Joel Kolstad) writes:
>In article <1992Nov17.165023.29174@julian.uwo.ca> wlsmith@valve.heart.rri.uwo.ca (Wayne Smith) writes:
>>I've got some big electrolytic caps (20000 to 60000 uf, 16 to 40 volts),
>>and I was thinking of putting them across the 5V and 12V power supplies
>>in my pc.  I would think that cap's that big would provide maybe 1
>>second of backup power.  
>
>I think that asking for one second would be a little much.  Here's hwy:
>
[ Maths deleted ]


>
>						---Joel Kolstad

Yes.....but putting capacitors this big across your PSU will totally blow the
output of the PSU....Consider the current that will flow at switch on....
It will be *huge* .... your PSU cannot supply this (unless you have a small
nuclear generator on hand.... :-) )

=============================================================================  
     _/      _/   _/   _/  _/   _/_/_/_/   |
    _/_/  _/_/   _/   _/_/     _/          |         Michael Brown
   _/  _/  _/   _/   _/       _/_/         |
  _/      _/   _/   _/_/     _/            |   cstadbg@csv.warwick.ac.uk
 _/      _/   _/   _/  _/   _/_/_/_/  _/   |
=============================================================================

Newsgroups: sci.electronics
From: Leonard Hermens <lhermens@eecs.wsu.edu>
Subject: Want to convert RGB to NTSC signals
X-Xxmessage-Id: <A731615B0101411A@fury.eecs.wsu.edu>
X-Xxdate: Thu, 19 Nov 92 15:20:59 GMT
Organization: Washington State University
X-Useragent: Nuntius v1.1.1d9
Date: Thu, 19 Nov 92 23:29:50 GMT

I need to convert RGB (red-green-blue) video signals to NTSC TV
standard video. I have RGB signals, black and white NTSC, and composite
sync signals available, but I don't know what device/circuit/wiring
is required to convert the RGB signals to NTSC.  

Could someone send me information about exisiting products that do this
or a
reference on how to build such a device? I know quite a bit of 
electronics, but don't know the relationships between RGB and NTSC
signals.

Thank you very much,
Leonard
Newsgroups: sci.electronics
From: pagorm@iastate.edu (Paul A Gormley)
Subject: Re: PCB FABRICATION
Organization: Iowa State University, Ames, IA
Date: Mon, 23 Nov 1992 06:06:09 GMT

	Ok I'll Take a shot here.  I put something on the net a while
back, but I, with my lack of net posting ability, screwed it up.  So,
I'll try again.  
	I'll start out by saying that I have only produced about sixty
boards in my time ranging in size from 2"X2" to 15"X21".  I will also
say that I have made all of these boards in make shift labs that I
could set up on very limited budget's.  Anyway here goes.

	I don't like most the application methods for P.C. board
etching.  I have found that when making two-sided boards it is rather
hard to do all the lining up when using the pens, stupid sticky tape,
iron on things, and this last method of toner transfer. I ahve only
ever had good results with screen printing transfers and that is a
real pain!
 I have had my best results using pmt's to expose photo-sensitized
boards. This is a rather simple method, although more expensive a
proposition than the transfer mehtods I have found it produces the
best results. 
	You start with pre-sensitized photosensitive board.  If you
have a very steady hand or the proper facilities you can sensitize
them yourself, but I have found the best results come from
professionally sensitized boards.  The idea here is to allow a UV wave
to either harden or break down the photosensitive material on the P.C.
board.  In this method, this is the material that protects the board
from the etchant.  In the positive method, whatever photosensitive
material is hit by the U.V. light is broken down, and washed off with
a developer.  (This is kinda like photography I've been told).  Then
the board is put into the etchant and etched like normal.  You really
can't see the protective material, but its there and it really works
well.  The negative process is the exact oposite in the way the
material is removed.  Only the areas that are hit by the U.V. harden
and the rest of it stays soft.  Then developer therefor, takes off the
unhardened material and the etching goes on like normal.  I have used
both of these methods also and can find advantages to both.  If you do
not want to spend a little cash on PMT's to expose boards, almost
necessary for negative process, and  have a plotter that has
transpearancy pens, then the positive method may be the way to go.  
	I have given my opinion here and hope that others will pitch
in on the discussion.  If anyone out there would like to discuss this
issue with me please respond to my e-mail address pagorm@iastate.edu.
Either questions or responses are very welcome.

					See ya around,
					Paul Gormley
					[@:{)
From: aw2t+@andrew.cmu.edu (Alex R.N. Wetmore)
Newsgroups: sci.electronics
Subject: Re: making mono from stereo
Date: 17 Nov 92 10:15:34 GMT
Article-I.D.: andrew.wf2J=aK00iUy05JRVP
Organization: Sophomore, Math/Computer Science, Carnegie Mellon, Pittsburgh, PA

Excerpts from netnews.sci.electronics: 17-Nov-92 Re: making mono from
stereo by GNR100@psuvm.psu.edu 
>   I know that there is no way to tell which channel a part of the
waveform cam
>  
> from,  but is there some way to create "artificial" stereo, say, by having a
> computer divide the signal up into two channels so is sounds halfway decent?

I know that there are some algorithms for doing just this.  Heathkit
used (maybe they still do, although I have heard rumors that they went
under) to sell a kit to make a fake-stereo from a mono (as I remember is
was about $10).

I'm sure someone out in netland has the skematic for it (or a similar circut).

alex
Newsgroups: sci.electronics
From: u009@csx.cciw.ca (G. Stewart Beal)
Subject: Re: 8-bit video chip needed
Organization: Canada Centre for Inland Waters
Distribution: usa
Date: Mon, 23 Nov 1992 16:35:15 GMT

In article <sad.722460663@camelot> sad@camelot.bradley.edu (Shrijay Dalal) writes:
>Hello,
>
>Anyone know which are good 8-bit video chips to use to display to a
>composite screen (TV) and is relatively easy to use and come by?
>
>Thank you,
>Shrijay
>
>--
>Shrijay Dalal                       | "Sometimes I think the surest sign that 
>sad@camelot.bradley.edu             | intelligent life exists elsewhere in the
>Student Computer Trainer            | universe is that none of it has tried
>Bradley University                  | to contact us." -- Calvin of C&H

6847's are fairly easy to use. The clock arrangement permits it to control
psuedo dual porting to avoid snow on screen updates.
 
Regards, Stu Beal, VE3MWM, U009@CS.CCIW.CA,
National Water Research Institute, Burlington, Ontario, Canada.
 
"She was a definite '10': a '5' with a high paying job." - Cole B. Kiser
 


Newsgroups: sci.electronics
From: johnh@macadam.mpce.mq.edu.au (John Haddy)
Subject: Re: VGA feature connector pinout
Organization: Macquarie University, Sydney
Date: Wed, 18 Nov 1992 06:51:47 GMT

In article <truben.721928059@vipunen.hut.fi>, truben@vipunen.hut.fi (Trygve Nyman) writes:
|> Anybody got the pinout of the feature connector
|> found on most VGA-cards? Complete specifications
|> and points to litterature would be even better...
|> 
|> Thanks,
|> truben
|> 

Before it got nicked, I had a good book "The programmers guide to the EGA/VGA" -
published by Brady (I think). This, from recollection, had all you needed to know.

I _think_ that the VGA feature connector may be the same as the EGA one. If so,
here is the data (from the IBM EGA Technical Reference):

	GND	1	2	-12V
	+12V	.	.	J1
	J2	.	.	G'OUT
	R'OUT	.	.	B'OUT
	ATRS/L	.	.	BOUT
	GOUT	.	.	G
	R'	.	.	B
	R	.	.	ROUT
	FEAT1	.	.	BLANK
	FEAT0	.	.	FC1
	FC0	.	.	G'/I
	B'/V	.	.	HIN
	VIN	.	.	14MHz
	Int.	.	.	EXT OSC
	VOUT	.	.	HOUT
	GND	31	32	+5V

Signal Description:

("inputs" are signals coming _from_ the EGA, "outputs" are signals going _to_ the
EGA via the feature connector. (typical IBM :-))

J2	this pin is connected to auxiliary jack 2 on the rear panel. (Obviously
not applicable to the VGA)

R'OUT	secondary red output

ATRS/L	attribute shift load. This signal controls the serialisation of the video
information. The shift register parallel loads at the dot clock leading edge when
this signal is low.

GOUT	primary green output

R'	secondary red input

R	primary red input

FC1	this signal is input from bit 1 (Feature Control Bit 1) of the feature
control register.

FC0	this signal is input from bit 0 (Feature Control Bit 0) of the feature
control register.

FEAT0	this signal is output to bit 5 (Feature Code 0) of Input Status Register 0	

B'/V	secondary blue input/monochrome video

VIN	vertical retrace input

Int.	this signal is output to bit 4 (Disable Internal Video Drivers) of the
Miscellaneous Output Register.

VOUT	vertical retrace output

J1	this pin is connected to auxiliary jack 1 on the rear panel.

G'OUT	secondary green output

B'OUT	secondary blue output

BOUT	blue output

G	green input

B	blue input

ROUT	red output

BLANK	this is a composite horizontal and vertical blanking signal from the CRTC

FEAT1	this signal is output to bit 6 (Feature Code 1) of Input Status Register 0

G'/I	secondary green/intensity input

HIN	horizontal retrace input from the CRTC

14MHz	clock from the system board

EXT OSC	external dot clock output

HOUT	horizontal retrace output

		CRTC = CRT Controller

Hope this helps.

	JohnH

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

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

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

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