HDTenEightyP/NetNews huggingface dataset:
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Grounded soldering iron tip
Date: Sun, 11 Oct 1992 23:43:16 GMT
Organization: U of Toronto Zoology

I wrote:
>>I have found that using unground-tip soldering pencils on CMOS
>>IC's will blow up the IC *every* time.
>
>I've used my non-grounded-tip iron on 4000-series CMOS without problems.
>*However*, this is a Weller transformer-base iron, so the tip may not be
>grounded but it probably is fairly effectively isolated.

At Dave Martindale's suggestion, I checked my iron out with an ohmmeter...
and although it was not *advertised* as grounded-tip, and doesn't have
the right model number to be grounded-tip, in fact the tip appears to be
grounded pretty effectively, with only a fraction of an ohm between tip
and the AC plug's ground pin.  (And yes, the resistance between the tip
and the other AC-plug pins is infinite.)
-- 
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  henry@zoo.toronto.edu  utzoo!henry
From: bwood@diva.Berkeley.EDU (Blake Philip Wood)
Newsgroups: sci.electronics
Subject: Re: 25 ohm coax cable
Date: 8 Oct 1992 13:15:37 GMT
Organization: /etc/organizaton
NNTP-Posting-Host: diva.berkeley.edu
Keywords: coax cable

>dhina@dxcern.cern.ch (Mourad Dhina) writes:
>
>semi-rigid coax cable of 25 ohms impedance... anybody know where to find this?

Looking at a table of about 95 different types of coax, I see that none have
impedances below 50 ohms, so I suspect 25 ohm coax is not available.
If you need only a short piece, you might try making it yourself, using

Z0=(276/sqrt(epsilon)) ln(b/a)

where epsilon is the relative dielectric constant of the material between
the conductors (1 for air, 2-5 for most plastics), a is the radius of 
the inner conductor and b the radius of the outer conductor.

This info and the coax table are in "Building Scientific Apparatus: A 
Practical Guide to Design and Construction", by Moore, Davis, and Coplan.
A highly recommended book!

-- 
                 Blake P. Wood - bpw@ctxsys.lanl.gov (505) 665-6524
                 Group P-1, MS-E526, LANL, Los Alamos, NM  87545
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: new PIC microcontroller
Date: Fri, 9 Oct 1992 18:48:01 GMT
Organization: U of Toronto Zoology

In article <2ad347e8.nw@nw.com> mkl@nw.com (Mark Lottor) writes:
>The chip can also can be programmed over a two-wire serial line...

The real question is:  are the programming specs in the datasheet?

It's really quite irrelevant how many wires are involved if you have
to buy a commercial programmer anyway.
-- 
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  henry@zoo.toronto.edu  utzoo!henry
Newsgroups: sci.electronics
From: ssave@ole.cdac.com (The Devil Reincarnate)
Subject: Re: Need Help with Op-Amps
Organization: CDAC, WA
Date: Fri, 9 Oct 1992 20:34:17 GMT

In article <9988@ncrwat.Waterloo.NCR.COM> tjgerman@53iss6.Waterloo.NCR.COM (Trevor German) writes:
>
>Re: steuer questions
> [STUFF ABOUT OPAMP GAIN DELETED]


   I have a similar question about op-amps.  This is what I want to do:


  I have an input sinusoidal signal.  This will be of a real-time variable
frequency. (That's the problem).  What I want is an inverse of this signal
that is exactly 180 deg. out of phase with it.  If I pass it through an 
inverting amplifier, I will introduce a delay in the signal as I pass it
through the circuitry.  I can't live with this delay. Upto 2 deg. 

  I need suggestions that will look at the output and input of the inverting 
amp. and delay the output so that the input and output are *EXACTLY* 180 deg. 
out of phase.  I can't (don't want to) touch the input. Maybe someone has 
ideas of reeeeaaaal fast inverting amplifier designs, etc.

  It has to be instantaneous, some sort of feedback, without any degradation
of the signals, ie. bucket brigade and charge storage is out.  The freq. range
is DC (ok, 1Hz) to 20 KHz.  


Any help will be appreciated.

Thanks,
Shailendra
ssave@ole.cdac.com
From: kad@ip29!bob (Keith Drescher ip30)
Newsgroups: sci.electronics
Subject: Re: Help! My CD player sk-sk-sk-sk-skips
Keywords: CD players, useful book
Date: 7 Oct 92 14:05:12 GMT
Distribution: usa
Organization: InterBold

In article <1992Oct6.133346.9528@mcs.anl.gov> hoffberg@phebos.aps.anl.gov (Mike G. Hoffberg) writes:
>In article <1992Oct2.152431.10629@ip29!bob> kad@ip29!bob (Keith Drescher ip30) writes:
>>
>>But a caveat:
>>I found a book on CD repair that tells how to do it right -
>>          ^^^^^^^^^^^^^^^^^
>>Keith Drescher
>
>(since e-mail seemed to bounce)
>
>What is the name of this book, and where do I find it?
>
I'll post this since our Email doesn't work quite right - hopefully this
will end any further postings for the book name.
The name of the book is:
Title:  Troubleshooting and repairing compact disc players.
Author: Homer L. Davidson
Publisher: TAB
There are copies at several local libraries here, but since it's a TAB book
many small electronic stores tend to carry TAB books in my experience.  Also
find any TAB book and the last page usually lists other available titles
and tells how to order them direct from the publisher.  The book covers 
several older models of CD player and was published in 1988.
Newsgroups: sci.electronics
From: darek@gpu.utcs.utoronto.ca (Darek Dabrowski)
Subject: pins for null modem ??? help..
Organization: UTCS Public Access
Distribution: ont
Date: Mon, 12 Oct 1992 15:50:41 GMT

I need the pins that are used for null modem cable. (serial port..)


	there are 25 pins which should be connected and how ???

	1 . . . . 5 . . . . 1 . . . . 5 . . . . 2 . . . . 5


	1 . . . . 5 . . . . 1 . . . . 5 . . . . 2 . . . . 5

I know that pin 3 should be connected to 4 and 6 & 8 to 20 but 
this doesn't work... I want to connect XT with 486 could this be a problem ??

						Darek
dpdabrow@descartes.uwaterloo.ca
darek@gpu.utcs.utoronto.ca
From: rduflon@cup.portal.com (Raymond H DuFlon)
Newsgroups: sci.electronics
Subject: WANTED: 8052-Basic Controller Board
Date: Wed, 14 Oct 92 15:25:20 PDT
Organization: The Portal System (TM)
Distribution: usa

I'm looking to buy a new or used 8052-Basic based microcontroller board.  It
will be the "brains" of a simple robot under development by a third grade
class, so price is somewhat important.  If you have one to sell or know of
any that are commercially available, your response is appreciated!

Ray
rduflon@cup.portal.com
From: witters@tc.fluke.COM (John Witters)
Newsgroups: sci.electronics
Subject: Re: Help with tube amp requested.
Date: 12 Oct 92 16:31:03 GMT
Organization: John Fluke Mfg. Co., Inc., Everett, WA

In article <1840072@hpsad.sad.hp.com> smithj@hpsad.sad.hp.com (Jim Smith) writes:
>
>Unfortunately, since tube heaters are not user-replaceable, there's not
>much that you can do.  If your Stereomaster has any screwy-turny-thingies,
>you might want to diddle them and see if you can get your anodes to respond
>by ungetting their emissions blankers, but if any Nyquist Eddies occur during
>this procedure, I can't be held responsible for the outcome.

Jim, you forgot to tell him to use a grid leak drip pan!  If your turn one of
those thingies too far, you'll end up ankle deep in electrons as they spew out
onto the floor.  This could be dangerous if you're not wearing insulating
non-skid footwear.  I think you were irresponsible for suggesting that an
amateur should diddle with it without taking precautions.  I don't think
disclaiming responsibility after making the suggestion was an ethical thing to
do either.  It gives our profession a bad image.

-John

-- 
    *  *  *		John Witters			voice:	(206) 356-5274
  *  \      *		John Fluke Mfg. Co. Inc.
 *    \      *		P.O.B. 9090 M/S 241F		fax:	(206) 356-5116
*    DRIPS    *		Everett, Washington  98206-9090	     or (206) 356-5174
 *      \    *
  *      \  *		domain:	witters@tc.fluke.COM
    *  *  *		ARPA:	fluke!witters@uw-beaver.ARPA
			uucp:	{uunet,sun,microsoft,uw-beaver}!fluke!witters
Hi! I'm a .signature virus!  Add me to your .signature and join in the fun!
From: an938@cleveland.Freenet.Edu (George II Lenzer)
Newsgroups: sci.electronics
Subject: Need info: Audio Digitizers
Date: 12 Oct 1992 08:37:15 GMT
Organization: Case Western Reserve University, Cleveland, Ohio (USA)
NNTP-Posting-Host: slc10.ins.cwru.edu


	I would like to hear from anyone with info on building a
digital sampling module for low quality applications.  It doesn't
need to be Hi-Fi, just intelligible.  Requires non-volatile/
erasable storage for samples (more than one).  If anyone has any
suggestions, please E-mail me.
						Thanks,
						George II Lenzer

-- 
"I'll let you in on a little secret.
	The whole universe is totally INSANE!!!!"
						Mr. Natural
From: tony@scotty.dccs.upenn.edu (Anthony Olejnik)
Newsgroups: sci.electronics
Subject: I`m new to cable TV and I have some Qs on converters
Date: 7 Oct 92 12:50:08 GMT
Distribution: usa
Organization: University of Pennsylvania


I`ve just got the (basic) cable TV service (ie. no HBO, PRISIM, etc.)
Since I have a cable ready TV, I apparently don't need a channel converter.

	Q1.)  Am I right?  
	Q2.)  What`s the purpose of the `channel converter' anyway?
	Q3.)  If I did decide on the extended services (HBO, PRISM, etc.),
              can I do it with my cable ready TV?   Do I really need the
	      the `channel converter'?
	Q4.)  Apparently the cable TV companies rent out the channel
              converters.  If I want the extended services, but don't want 
              to spend the rental fee, can I buy (from the back of some
              magazines) my own converter?  Will it work with my cable TV
              company?  There are a number of different brands/models to
	      choose from.  How do I know which one to buy?
	Q5.)  If I buy (from the back of some magazines) my own converter,
              can I get the extended services (HBO, PRISM, etc.) for free
              (since I already have my own converter)?
	Q6.)  My cable TV company has a pay-per-view channel.  The 
              advertisements for this channel indicates that 2 different
              converters (Jerrod and Sprucer) could be used.  If I had
	      one of these two, could I see the pay-per-view movies for
	      free?  The advertisements indicate some sort of code number
              that must be entered into the channel converter (and then
              you must switch to a special channel) in order to see the
              movie.  How do I get that code number?  Is it something
              specific to my conerter box?  If so, if I buy my own box,
              how will I know what the code number is?

I`m new to this cable TV stuff and I appreciate any help.
Thanks in advance.

--tony
Newsgroups: sci.electronics
From: iqbal@kaw.eel.ufl.edu (M.Iqbal)
Subject: Re: Student version of SPICE???
Organization: University of Florida
Date: Tue, 13 Oct 92 21:55:46 GMT

In article <BvzJEK.922@news.cso.uiuc.edu>, rky57514@uxa.cso.uiuc.edu (Tall Cool One ) writes:
|> huey@athena.mit.edu (Huy Le) writes:
|> 
|> >In article <1992Oct9.143138.203047@uctvax.uct.ac.za>, clrmic08@uctvax.uct.ac.za writes:
|> >|> Is there a student or demo version of SPICE around. If so where can I get 
|> >|> a copy from ? An FTP site would be the most convenient. 
|> >|> Thanks
|> >|> Mike
|> 
|> 
|> >I know the company MicroSims in California does send out free demo
|> >copies of Spice, but I dont have their address off hand.
|> 
|> 
|> >HL
|> 
|> You can get PSpice from wuarchive.wustl.edu.  It's in pub/msdos/electrical, I
|> think.  I got an evaluation copy of PSpice from there.  Good luck!
|> 

That is not the right path. The pspice is under mirrors/msdos/electrical


-- 

------------------------------------------------------------------
                                            
      						 >><<<     >>><<<<
Iqbal@sioux.eel.ufl.edu		 		 (o o)     (o) (o)
University of Florida				 [ | ]        | 
                                  		   -         ---
From: mcovingt@aisun3.ai.uga.edu (Michael Covington)
Newsgroups: sci.electronics
Subject: Re: Can I use 1 power supply instead of 2 9-volt batteries?
Date: 16 Oct 92 03:08:05 GMT
Distribution: na
Organization: AI Programs, University of Georgia, Athens

In article <1992Oct15.180350.23610@netcom.com> kehoe@netcom.com (Thomas David Kehoe) writes:
>My op-amp prototype uses two 9-volt batteries, to supply
>+9 volts, -9 volts, and ground.  It requires new batteries
>after 5-10 hours of use, and I have a 9-volt power supply
>(that plugs into the wall).  Replacing the +9 volts battery
>with the power supply will be easy.  Is there an easy way
>to replace the -9 volt battery?
>
>Would an inverting op-amp do this? 

No. An op-amp can only output voltages that are within the range of
voltages supplied to it.

>The alternative is to use op-amps that just require +9 volts
>and ground.  I could so this too.

Might not simplify the job much; "single-supply" op-amps are just like
ordinary ones except with a slightly wider voltage swing.  They address
the problem that when you're using a single supply, your total voltage
range is less (like 0 to 9 rather than -9 to +9).  But they are not
fundamentaly different in any way.

Your simplest solution will be to get Radio Shack's power supply
booklet and build yourself a split power supply (something I've been
meaning to do for years) [build it, I mean].






-- 
:- Michael A. Covington     internet mcovingt@uga.cc.uga.edu 
:- Artificial Intelligence Programs       phone 706 542-0359
:- The University of Georgia                fax 706 542-0349
:- Athens, Georgia 30602 U.S.A.          amateur radio N4TMI
From: cyberman@toz.buffalo.ny.us (Cyberman)
Newsgroups: sci.electronics
Subject: Re: Bad customer relations; was: Re: archive server for pa
Date: 8 Oct 92 03:24:58 GMT
Organization: The Tower of Zot - (716)691-3865

mcovingt@aisun3.ai.uga.edu (Michael Covington) writes:
> That is why Maxim, Dallas Semiconductor, and Mini-Circuits are going to
> rise up and give the big companies some stiff competition.

I hope so INTEL CERTAINLY needs a GOOD swift FREAKING kick.

> It's been done before.  Remember a little software company 
called Borland
>
Oh yeah the poeple who made a full blown pascal compilor that 
was only 64k! :)

Cyberman - they do need to SHRINK thier products though  
 


************************************************************
* Cyberman@TOZ.BUFFALO.NY.US                               *
*   "Life is what you put into it" - Cyberman              *
* Optimistic - running through a barn of manure looking    *
* for the horse!  /\ [] ( )                                *
From: karol+@pitt.edu (Filip M. Gieszczykiewicz (fmgst+@pitt.edu))
Newsgroups: sci.electronics
Subject: EPSON LQ-1050 (head) WANTED or (without head) FOR SALE
Summary: have printer, need head or info, head-less printer 4sale
Keywords: epson, print-head, LQ-1050, plezzze..
Date: 9 Oct 92 07:42:55 GMT
Followup-To: sci.electronics
Distribution: usa
Organization: University of Pittsburgh


	PLEASE REPLY TO fmgst+@pitt.edu NOT HERE. THANK YOU.

	Greetings. My Epson LQ-1050 printer expired today. I use it
	a LOT (it has serviced about 15-20 boxes of paper :-) and
	the print-head is dead. I took it apart and 2 pins are quite
	dead - their coils are black... (the drive electronics are
	fine and the printer otherwise works great).

	Does anyone have a used but good printhead? If not, anyone
	know the price for a new one and where to get one? I've heard
	that there are companies that sell new or rebuilt heads. Does
	anyone know how much one of these runs? ($$).

	Also, I may be interested in purchasing someone's printer
	that has dead electronics or PS. Thanks in advance.

	Take care.

	PLEASE REPLY TO fmgst+@pitt.edu NOT HERE. THANK YOU.
-- 
-------------------------------------------------------------------------------
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". Looking for donations of 
parts for a home-built airplane: engines, Al tubing, canvas, bolts, prop, etc!
From: dcg5662@hertz.njit.edu (Dave Grabowski (KxiK))
Newsgroups: sci.electronics
Subject: Re: Serial line booster
Date: 12 Oct 92 18:58:55 GMT
Organization: New Jersey Institute of Technology, Newark, N.J.

In article <BvzFos.KFz@acsu.buffalo.edu> stock@acsu.buffalo.edu (Matthew D. Stock) writes:
>Hello.  Right now I've got a serial cable running between two PCs that is
>approximately 50 feet long.  By using loopback tests, I've detramined that
>all of the cables are working correctly, but one of the serial cards so too
>weak to transmit the whole distance.
>  What I was thinking of doing is adding a booster midway between the two
>systems, but I am not sure the best way to do it.  Any ideas?
>Thanks,
>  -Matt
>
>-- 
>Matthew D. Stock         | think(X):- am(X).
>stock@cs.buffalo.edu     | think(i).
>			 | :? am(i).
>CS @ Buffalo             | yes.

  Well, there's a couple things you can do. You could check the "weak"
serial card and see if it has a power supply that could use some
upgrading, or perhaps a bad driver (75188, 1488, I think). Your other
alternative would be to either buy or make boosters. About a year ago, I
had to run a serial line from the 3rd to the 26th floor of Merrill Lynch
in New York City for their cash register to a backroom computer. Using
RS-232 to RS-422 booster boxes at both ends purchased from B&B
electronics, the connection was perfect at 9600 baud.

-Dave
-- 
-----------------------------------------------------------------------------
Kappa Xi Kappa - Over & Above!                         dcg5662@hertz.njit.edu
9 Sussex Ave., Newark, NJ (car theft capital USA)   70721.2222@compuserve.com
Newsgroups: sci.electronics
From: sudesh@utkal.njit.edu (T. J. Sudesh)
Newsgroups: sci.electronics
Subject: Panasonic (PV 4210) 4 hd vcr fro sale!!
Date: 13 Oct 92 14:22:34 GMT
Organization: New Jersey Institute of Technology, Newark, N.J.


	Hi,
   Panasonic 4 Head vcr for sale !!!
The model # PV-4210 (SAME AS PV4210 + COUNTER & PROGRAM DIRECTOR)
THE VCR IS LESS THAN 2 MONTHS OLD...
THE FEATURES ARE:

	1) AUTOMATIC DIGITAL TRACKING
	2) PROGRAM DIRECTOR (MAKES PROGRAMMING EASY)
	3) SVHS QUASI PLAY BACK (VHS RESOLUTION)
	4) BI LINGUAL (ENG/SPAN)
	5) 181-CH COMPATIBLE
	6) MULTI-EVENT PROGRAMMING
	7) THREE SPEED REC/PLAY
	8) GOT ALL THE FEATURES THAT NORMAL VCRS HAVE

		QOUTING A PRICE OF $170...

CALL SUDESH/E-MAIL, AT (201)596-8294 (9AM - 6PM)
	               (201)955-0143 (7PM - 11PM)
From: diegert@cs.sandia.gov (Carl F. Diegert)
Newsgroups: sci.electronics
Subject: Wirewrap proto with 18x18 PGA
Date: 15 Oct 92 23:04:46 GMT
Organization: Sandia National Laboratories, Albuquerque, NM
Originator: diegert@cs.sandia.gov

We need a better solution for wire-wrapped prototypes
using 18 by 18 PGA parts. Without a ZIF socket, you have
to stand on these things. The only ZIF we have found,
however, has pins too short and small for our prototype,
and too thin to plug into a standard, non-ZIF
wirewrap socket. 

.. there must be a solution .. thanks in advance for
any help!
From: agodwin@acorn.co.uk (Adrian Godwin)
Newsgroups: sci.electronics
Subject: Re: Looking for 0.025" sq. pin jumper wires
Date: 16 Oct 92 09:14:54 GMT
Organization: Acorn Computers Ltd, Cambridge, UK

In article <bgupta.719180935@micro> bgupta@micro.caltech.edu (Bhusan Gupta) writes:
>Hi all,
>
>I am looking for a wire jumper on whose ends are connectors for a 0.025in
>square pin header. I know that ITT Pomona sells them (part #4741), but their
>delivery is 4-6 weeks @ $3 per jumper. Does anybody know who else makes them
>and how much, etc.? The length I am interested in is less than 12 inches.
>Textronix also sells these beasts as part of their SOIC kits (to connect chip
>clips to other probes), but they do not unbundle these electrical leads.
>

E-Z-Hook
225 N Second Ave
Arcadia, CA 91006
(818) 446-6175

are a major source of lots of useful bits like this. However, they probably
aren't any cheaper than Pomona (in fact, there's a good chance the Pomona
parts come from E-Z-Hook). The UK distributor (Astra Cables) sells a part
like the one you describe (9110 series) for about 3 pounds : that's about
a 100% markup on your price, and is typical of US-sourced parts in the UK :-(.

You may be able to get the individual socket parts and make your own. Again,
E-Z-Hook sells them, and Berg (now part of DuPont, I think) may sell them a
great deal cheaper if you buy a few hundred. I can't find a Berg catalogue
to check this, but I know they make strips of sockets that will fit, and may
well make a strip length of 1.

If you try to make your own, you'll need a specialist crimp tool. If you don't
have something suitable already, this may cost > $100.

-adrian


-- 
Adrian Godwin : agodwin@acorn.co.uk : adrian@fangorn.demon.co.uk : g7hwn@gb7khw
ObDisclaimer  : I believe this rubbish .. don't imagine that anyone else does.
Newsgroups: sci.electronics
From: tchannon@black.demon.co.uk (Tim Channon)
ReplyTo: tchannon@black.demon.co.uk
Subject: Re: what's a SAW?
Distribution: world
X-Mailer: cppnews $Revision: 1.18 $
Organization: null
Date: Wed, 14 Oct 1992 02:16:29 +0000

> >Could someone explain what a SAW filter is and what it is used
> >for? ( the $.25 explanation will do )
> 
>         Surface Acoustic Wave filters are analog computational elements
> usually used to perform correlations.  They're typically used with

And just about every TV set uses one!

In this case it is used as a high performance bandpass filter and works at IF 
frequencies -- 30..40MHz or maybe much higher.

An analogy is a tranversal filter which shows similar charactersitics. The 
excellent group delay characteristic provided one of the big advances in TV 
performance in recent years.

  TC. 
    E-mail: tchannon@black.demon.co.uk or tchannon@cix.compulink.co.uk
                                
Newsgroups: sci.electronics
From: ken@syd.dit.CSIRO.AU (Ken Yap)
Subject: Re: Mystery Part!
Organization: CSIRO Division of Info Tech, Sydney, Australia
Date: Thu, 8 Oct 92 03:25:03 GMT

|The BUZ prefix sounds like a power MOSFET.

Sounds plausible. In the Pro-Electron scheme B = silicon, U = high
power if I remember correctly.
Newsgroups: sci.electronics
From: jdkirby@vaxa.weeg.uiowa.edu (Student Account)
Subject: z80 C compiler
News-Software: VAX/VMS VNEWS 1.41    
Organization: University of Iowa, Iowa City, IA, USA
Distribution: usa
Date: Wed, 7 Oct 1992 22:00:00 GMT

I am looking for a C compiler for the Z80 microprocessor. The
compiler needs to run on the IBM PC. Please E_mail any responses
to jdkirby@vaxa.weeg.uiowa.edu. Thanks.