HDTenEightyP/NetNews huggingface dataset:
From: roger@odie.cs.mun.ca (Roger White)
Subject: VCR Repairman Problem
Summary: Fixed 1 month ago, guaranteed 6 months, don't work now, won't fix
Organization: CS Dept., Memorial University of Newfoundland
Date: Wed, 22 Jul 1992 21:33:29 GMT

I own an RCA VCR model # VMT295, this is a stereo VCR. We sent it in for
repairs around a 1.5 months ago (Tape wouldn't eject, turn on VCR immediately
turns off by itself). We recieved it back and noticed a "little" problem,
the first tape we played had a snowy screen. This problem rectified itself
after 10 minutes through... we thought nothing of it. 

A few days later we noticed it again, this time it stayed snowy longer...
we phoned the VCR clinic, they said dirty heads; bring it in whenever you
can for a free cleaning. The problem went away again so we forgot about
getting the heads cleaned.

The third time this happened we phoned him again, they said dirty heads...
we brought the machine down and they cleaned the heads but the problem wasn't
fixed. They could temporarily fix it by touching an IC so they concluded the IC
was at fault and they would repair it (Free of charge since their original
work had a 6 month guarantee).

Now it has been two weeks since it has been put in and they claim that it will
cost $75 for the "new" IC. They have to order it from RCA, who has to order it
from Hitachi, and the final cost will be well over $100... so he says that he
doesn't think this repair is worth the cost. He claims the IC is one of the
main IC's for the VCR and there is no other fix except to get a new one, it
only seemed to me like a loose connection... is it possible that the IC is
"going bad" (to quote him directly)?

Some added comments, he said that this problem developed after they fixed the
machine first... therefore they won't cover it under the guarantee. Since he
said it will be fixed free of charge (I have a witness but nothing in writing)
do I have any right to request it be fixed free? He will take a trade in on 
the VCR (for the amount of the first fix) and put it toward the price of a
new VCR. I just want my VCR fixed, or my money refunded from the first "fix".

Do I have any course of action? I haven't spoken with him face to face about
it yet, so I don't know if I will have problems... I just want some advice
just in case some problems arise.

Thanks,
Roger White

-- 
Boot it up? I did A LOT of that!| Roger White
		(Sam-Cheers)	| Memorial University of Newfoundland
--------------------------------| St. John's, Newfoundland, Canada
roger@odie.mun.edu, roger@odie.cs.mun.ca, roger@garfield.cs.mun.ca
Newsgroups: sci.electronics,rec.photo
From: strong@tc.fluke.COM (Norm Strong)
Subject: Re: 1.5 volt lithium batteries?
Organization: John Fluke Mfg. Co., Inc., Everett, WA
Date: Thu, 23 Jul 1992 14:17:41 GMT

In article <PHR.92Jul19233515@soda.berkeley.edu> phr@soda.berkeley.edu (Paul Rubin) writes:
}I've seen some references to 1.5 volt lithium batteries starting
}to become available in conventional battery sizes (e.g. AA).
}Anyone know where I can get some, how much they cost, and what
}their energy density is compared to alkaline batteries?  Thanks.

Eveready makes them; they're called LithEon.  I have several samples of
the AA size.   They seems to have about twice the energy density of
alkaline batteries.  I don't know the retail price, but I'm pretty sure
they sell for more than twice the price of alkaline cells.  

-- 

Norm Strong  (strong@tc.fluke.com)
2528 31st S.   Seattle WA 98144   USA
Newsgroups: sci.electronics,rec.video
From: ncc1701@madoka.its.rpi.edu (Mark O. Chadwick)
Subject: Re: Blue Lasers
Reply-To: ncc1701@acm.rpi.edu
Date: Mon, 27 Jul 1992 21:12:55 GMT

tmkk@uiuc.edu (Khan) writes:

>I heard a brief tidbit in one of the popular media about (IBM?)
>inventing a blue laser, making extremely high resolution laser
>projection TVs possible by using a red, a green, and a blue laser in
>combination. Ultra high res, no visible pixels, etc. etc. Sounds like a
>videophile's dream come true. Anyone know any more about this new
>development? Will it make LCD light valve projectors obsolete before
>they even get to market en masse?

Hmm...I doubt it.  A couple of friends and I built a laser-sourced
projection TV in college (red only) and had tremendous problems in
controlling flicker.  We could get rid of it, but only at the
expense of a jittery picture and almost NO brightness, or lotsa
brightness, stable picture, and LOTS of flicker.
I doubt lasers will be a viable alternative until there is some method
of building very fast scanning apparatus and make them fail-safe as
well.  (You'd need powerful lasers for decent brightness in a 
naturally lit room, and if your scanning device fails, you're
liable to burn a hole in the wall or someone's eyes...)


>BTW, the shorter wavelength of the blue laser is also supposed to allow
>much higher storage densities on laser-read media (CDs, LDs). Several
>hours' worth of music would be able to fit on a 5" CD, and LDs would for
>the first time be able to hold a full movie's worth of HDTV info
>(current LD technology can only hold a few minutes' worth of HDTV
>program).


Now, THIS is what I'm waiting for!  I heard some stuff on this too,
but it was all rather sketchy.  Anyone else hear anything?


-- 
---
Mark "Emerson" Chadwick -- ncc1701@acm.rpi.edu    chadwickmo@space.laafb.af.mil
Newsgroups: sci.electronics
From: bbs.lar@tsoft.sf-bay.org (Larry Greenfield)
Subject: HDTV
Organization: The TSoft BBS and Public Access Unix, +1 415 969 8238
Date: Sat, 25 Jul 1992 01:29:24 GMT

Hello all, I have a quick question.  I've been away and busy lately, and 
fear I may have missed some important news.
  Has the FCC (USA) finally picked an HDTV standard?  I read an article 
in the LA times hinting at that fact, but the use of language was unclear 
(it said that the US would not use Japan's standard).  Does this mean we 
have made our decision?   If so, which company's standard won out, and do 
you have any information on it?  
  Please *EMAIL* a response to me.
Thanks!!!  I really want to know!
:::::Larry:::::

--
Larry Greenfield (bbs.lar@tsoft.sf-bay.org)
Newsgroups: sci.electronics
From: cavers@menudo.uh.edu (Chris M. Cavers)
Subject: generators
Organization: University of Houston
Date: Tue, 21 Jul 1992 20:59:54 GMT

In looking over my car shop manual, the generator on my car is rated
as follows (leaving out the stuff about pulley ratios and polarity):

output   12v at 40amps
rated speed 5000rpm
operating speed 1000 - 13500rpm
Speed at which 14v is produced (at room temperature)  1000 or less rpm
Output current (hot)   2500rpm at 30amps or more
Operating condition  5000rpm at 40amps
Rotor coil resistance at 68 degrees f   3.9 ohms
Stator single coil resistance at 68 degrees f   0.10 ohms


My question is: Is there an easy way to determine the output characteristics
at various rpm (i.e. minimum rpm to produce 14v or 12v + how many
amps are produced at various rpms)?


Thanks in advance
From: kolstad@cae.wisc.edu (Joel Kolstad)
Newsgroups: sci.electronics
Subject: Re: 7 seg. Hex display driver IC?
Date: 27 Jul 92 01:30:08 GMT
Distribution: na
Organization: U of Wisconsin-Madison College of Engineering

In article <1992Jul25.195451.12675@ssc.wa.com> markz@ssc.wa.com (Mark Zenier) writes:
>In article <55066@mentor.cc.purdue.edu> falatic@mentor.cc.purdue.edu (MacGyver) writes:

[looking for hex --> 7 seg display]

>Both are either old or obscure (low volume) parts.  It would be
>cheaper to program a GAL/PAL or small EPROM and stick a uln2003 on the
>back.

Ah... but if you use that 74S288 as I suggested earlier, you don't even need
the ULN2003 -- it already has open collector outputs!  Quite useful.
From: andrewy@glas.apc.org (Andrew Yakovlev)
Newsgroups: sci.electronics
Subject: Help with 2SD1878!
Date: 30 Jul 92 20:37:19 GMT


       Hello!

     Could anybody tell what the internal structure of a 2SD1878 transistor is,
or are there any compatibles? This is  something  around  a  high-voltage  NPN,
though. It is used in a horizontal sweep pump curcuit  in  an  EGA  monitor.  I
suspect that the transistor has somewhat degraded, but can't get another one of
the same type down here. (Yea, I'm writing from Moscow... :-) And I can't  find
what other type could do the job instead, not knowing characteristics  of  this
one...

     If someone is going to Moscow soon, and could  take  the  transistor  with
him, I would be glad to buy it! (But let's discuss the price first. :)

     Many thanks in advance!

          Andrew.                       andrewy@glas.apc.org
From: ehare@arrl.org (Ed Hare KA1CV)
Newsgroups: sci.electronics
Subject: Re: SHOCKING STORIES
Date: 21 Jul 92 09:56:47 EDT
Organization: American Radio Relay League

In sci.electronics, feliccia@rodan.acs.syr.edu (Nicholas J Feliccia) writes:

>Ok. I want to know from the net people. What is the largest voltage shock
>you have ever received (and survived.) I am not talking about rewiring
>a light switch. I am talking about kissing the flyback transformer.

Nicholas,

Once, when I was about 15, I managed to get across a very stiff (capable
of >500 mA) 2000 volt d.c. plate supply. I saw stars. Come to think about 
it, I was very luck to see 16.

Higher voltages often send the body into such a convulsion that it throws
one away from the shock (a hazard in and of itself).

Now, I can't resist -- the flyback is not necessarily all that dangerous!
In most of the TVs I have seen, the internal resistance of the flyback
autotransformer windings will limit the current to quite a degree. I
would be more concerned with the approx 300 volt "low-voltage" end
at the horizontal output transistors and damping diodes (old timers 
substitute the term "vacuum tube" :-)  ).

As someone will certainly point out, it is the current that kills, not the
voltage.  However, this doesn't mean that a 12 volt 1000000 amp supply is
any more dangerous that a 12 volt 100 mA supply. The current that kills
it that which actually flows through your body (especially the heart). Body
resistance typically  varies from a few thousand ohms (wet with salt water) to
a few hundred thousand ohms. Ohm's law still applies. If one had a 1,000 ohm
body resistance, and got across 12 volts, a current of 12 mA would flow -- 
Annoying but not deadly (in most cases). 

73, Ed

-----
Ed Hare, KA1CV                  | ehare@arrl.org
American Radio Relay League     | 
225 Main St.                    |
Newington, CT  06111            | There is no limit to what you can 
(203) 666-1541 - voice          | accomplish if you don't care who
Senior ARRL Laboratory Engineer | gets the credit. - Harry S Truman
RFI, xmtr and rcvr testing      |  
-----
From: Ligon@macgw1.ge.com (Woody Ligon)
Newsgroups: sci.electronics
Subject: "Phonex" telephone wiring scheme
Date: 22 Jul 92 17:30:31 GMT
Distribution: usa
Organization: GE-CRD

Has anyone had experience with the "Phonex" telephone wiring gadget. It is 
regulaly advertized by "Heathkit" and others.  Supposedly it uses
a "base unit" to couple the phone line into your 110 V house wiring. 

It then uses "any number" of subunits to recover the telephone signal from
the house wiring at any available 110 outlet. It would seem to have the 
advantage of eliminating the need for telephone wiring inside the house and
it also might provide better signal quality when 2 or 3 extensions are being
used simultaneously. 

My questions to possible users are:  1. How is the sound quality?  and 2. 
Is it really possible to have a large number of subunits all in use 
simultaneously without losing sound quality?

Thanks in advance.  I will summarize useful responses to the NET. 

Woody Ligon
(ligon@macgw1.ge.com) 
Newsgroups: sci.electronics
From: tchannon@black.demon.co.uk (Tim Channon)
Subject: Life after CDs 
Distribution: world
Organization: null
Date: Fri, 24 Jul 1992 22:33:14 +0000

> I had always heard this 74 minute nonsense, then "Electric Ladyland" came
> out on one disc at 75:25. A couple years ago I got one by the Mexican
> band "Iconoclasta" that clocked in at 80:20.  What Gives ?
> 
Trickery.
Example: a blank CDR disk has a preformatted spiral at the required pitch 
(1.6u?). This could be closed slightly.

This spiral has a wobble @ 22.050kHz and a second wobble at a few hertz. As 
you will guess the CDR mechanism is not clever and will blindly adjust it's 
speed to lock to the wobble (the low one gives absolute time).

The 73 min disks have the wobble a bit faster, so the CDR responds by slowing 
the disk...

Squeezing more onto the disk is probably ultimately limited by what 
proportion of CD players will accept the disk. There are many pitfalls (sic).

  TC. 
    E-mail: tchannon@black.demon.co.uk or tchannon@cix.compulink.co.uk
                                
Xref: sparky sci.electronics:13550 rec.audio:10988 alt.folklore.computers:11372
From: agodwin@acorn.co.uk (Adrian Godwin)
Newsgroups: sci.electronics,rec.audio,alt.folklore.computers
Subject: Re: Two-sided CD's *DO* exist! (was Re: Life after CDs)
Date: 29 Jul 92 10:12:43 GMT
Organization: Acorn Computers Ltd, Cambridge, UK

In article <aldavi01.712267502@starbase.spd.louisville.edu> aldavi01@draconis.spd.louisville.edu (Arlie Davis) writes:
>
>One of Monty Python's albums (Matching Tie and Handkerchief, I think it
>is called) has *three* sides.  One side is normal, and one side has two
>grooves.  Depending on where you start the needle, you get one of the
>two tracks.
>

There was a Monty Python record with an unending track : the last groove
skipped back on itself, and played forever.

It ended :

Zzzzzzzzzzzzzip .. Sorry squire, I've scratched your rec- .. Sorry squire, I've
scratched your rec- .. Sorry squire, ........

-adrian


-- 
--------------------------------------------------------------------------
Adrian Godwin                                        (agodwin@acorn.co.uk)
From: frankb@hpsad.sad.hp.com (Frank Ball)
Date: Thu, 30 Jul 1992 17:56:43 GMT
Subject: Re: What's a Mini-Circuits MAR-6?
Organization: HP Signal Analysis Division - Rohnert Park, CA
Newsgroups: sci.electronics


*I just found some goodies in a corner of my office.  I suspect they are really
*nice goodies although I don't know exactly what they are (they were left by
*someone else).  I would appreciate any assistance in making a positive
*identification (exactly what the devices are, specs, pinouts).  Here's what
*information I have:
*
*Manufacturer: Mini-Circuits
*Part number: MAR-6
*very small round package; 4 pins, one pin at every 90 deg, one pin marked with
*a dot.

It is a "broadband monolithic amplifier".  50 ohms in/out.  DC-2 GHz.

gain in dB (typical):
100MHz	500MHz	1GHz	2GHz	min gain at 2GHz
20 dB	19 dB	16 dB	11 dB	9 dB

1dB gain compression point: 0dBm output
max input level (no damage): +15dBm
noise figure (typical): 2.8dB
third order intercept (typical): +15dBm
VSWR:  input 2:1  output 1.8:1  (worst case) 
16 mA 3.5V  
$1.29 each in quantities of 25.

The dot in the RF input. The lead across from it is the RF output and bias.
The other two leads are ground.  You need a resistor from the RF output
to your power supply.  Add a choke if you use a small resistor value.

You need blocking capacitors on input and output, so it doesn't really
go down to DC.

power supply:
+5V	+9V	+12V	+15V
98ohms	344ohms	531ohms	719ohms	(approximately)  There is some device to
device variation on the bias, but you want around 16 mA. It blows up at 50mA.

The SWR spec isn't terrific, but the spec is over the 2 GHz range.  They are 
much better below 500 MHz.  The charts show about 1.1:1 input and 1.2:1 
output at 500 MHz (typical numbers).

They can be useful for cheap preamps.

Frank Ball   1UR-M          frankb@hpsad.sad.hp.com
Hewlett Packard   
1212 Valley House Drive     (707) 794-4168 work  (707) 538-3693 home
Rohnert Park CA 94928-4999  KC6WUG Seca 750 XT350 IT175 DoD#7566 I'm the NRA.
From: harrold@mwk.uucp
Newsgroups: sci.electronics
Subject: NEED INFO. ON TRIANGULAR DIPOLE IMPEDANCE
Date: 28 Jul 92 06:54:46 CST
Organization: M. W. Kellogg, Houston TX

I would like to know what the impedance of a triangular dipole is.  My
son and I are building a UHF TV antenna.  We are using a corner reflector
type of design.  The triangular dipole is made out of sheet metal and looks
like a bowtie that is 14.5 inches long, with an included angle of 40 deg.  
Also we would like to know how to attach a 75 ohm coax cable to a regular
dipole of 72 ohms.  Do you just strip back the insulation and attach each
conductor to each half of the dipole or is there some type of ready made
connection device?  Thanks in advance!


Newsgroups: sci.electronics
From: kilian@cray.com (Alan Kilian)
Subject: Re: Phoneme based speach Synthesis chips ?
Organization: Cray Research, Inc.
Date: 23 Jul 92 13:21:56 CDT


RC Systems
121 W Winesap Road
Bothell, WA 98012     206-672-6909

Make a good board for $151.00 that takes the following:

Single characters:  It pronounces the letter
Words:	            It pronounces the english word
Sentences:          It pronounces the sentence with , ? and ! things
phonemes:           It pronounces the phoneme (For tough words)
Digitised sound     It outputs the sound through a D to A convertor

You can load in additional text-to-phoneme rules. It has a parallel and
serial port.

I like mine. Good quality english. Not fantastic, but good.

                         -Alan Kilian
-- 
 -Alan Kilian           kilian@cray.com 612.683.5499 (Work) 612.729.1652 (Home)
  Cray Research, Inc.   655 F Lone Oak Drive, Eagan  MN, 55121 
                        "It's based on actual math". -Dilbert
Newsgroups: sci.electronics
From: djw@lcs.mit.edu (David J. Wetherall)
Subject: computer VCR controller??
Reply-To: djw@lcs.mit.edu (David J. Wetherall)
Organization: MIT Laboratory for Computer Science
Date: Thu, 30 Jul 1992 16:29:03 GMT


Does anyone know of . . . a device that would let me control a VCR via workstation software?

Leads appreciated,

David Wetherall (djw@lcs.mit.edu)
Newsgroups: sci.electronics
From: kai@moci.uucp (Kai Bidstrup)
Subject: Re: What is an IGBT?
Organization: ICOM, Inc., West Allis, WI
Distribution: usa,sci
Date: Wed, 22 Jul 92 23:08:12 GMT

In article <1992Jul20.101533.13846@vax5.cit.cornell.edu> cpyy@vax5.cit.cornell.edu writes:
>> Can IGBT's amplify audio signal well?  Can they be used for Hi-Fi
>> audio power amplifiers?
>> 
>> Hiroshi
>> --
>> $BK\;3Gn;J(J   $BF|N)4pAC8&(J   motoyma@harl.hitachi.co.jp
>>                                     
>What are all these (VT100?) control characters supposed to do?  My machine
>doesn't receive them, but I'd like to know the effect.
>
>Where there's gain, there's potential audio amplification.  I've never
>used them in a linear amplifier, but I've made a few switch-mode
>jobbies with them.  The work quite nicely.  I was just doing single
>harmonic (at about 1kHz) amplification with them, but you can do
>much better with switch mode.  It's also incredibly efficient.  You
>can make a nice switch mode audio amp in a very small volume.  I've
>gotten a few kilowatts in about 10 cc's of power drive space (including
>heat sinking).  Don't let this out!  I don't want the stereo companies
>to start making amplifiers this way for a while. (-:
>  
>-- 
>
>Jon C. Russo
>internet : cpyy@vax5.cit.cornell.edu
>phone    : 607.277.3295

I don't know if any new power density records were broke (I think not),
but, Forte, a division of Threshold, has two class A ( 50W Stereo,
75W Mono ) and two class AB ( 150W Stereo & 200W Stereo ) that use
IGBT in the output stage.  Their glossy pamphlet even has 'IGBT'
plastered on the front.

Kai Bidstrup
ICOM Inc.
uwm!uwm.edu!moci!kai

Newsgroups: sci.electronics
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: RS-422A and RS-423.  Whats the diff?
Date: Sun, 26 Jul 1992 03:35:34 GMT
Organization: U of Toronto Zoology

In article <2445@tau-ceti.isc-br.com> jimc@tau-ceti.isc-br.com (Jim Cathey) writes:
>... I know that our RS-422 devices
>used +5V only on the drivers, and I seem to remember that this is
>allowed by the spec...

It's required, in fact.

>RS-423 uses the same voltage swing as RS-422...

No; correct 423 uses twice the swing, from -5 to +5.

>... Many RS-422
>driver chips have a mode pin by which you can get twice as many RS-423
>transmitters by strapping it so. 

Only if you also switch one of the power-supply pins from ground to -5.
The data sheets do not call attention to this, but it's there in the
diagrams if you look for it.

As others have mentioned, the Macs do RS423 -- swings from -5 to +5 --
for all signals, with some of the signals made available as a pseudo-422
pair of signals with opposite polarities.  The imitation is good enough
that many true 422 implementations will interoperate with it, but it is
not correct 422.
-- 
There is nothing wrong with making      | Henry Spencer @ U of Toronto Zoology
mistakes, but... make *new* ones. -D.Sim|  henry@zoo.toronto.edu  utzoo!henry
Newsgroups: sci.electronics
From: marina@tk.mainet.msk.su (Naumenko M.V.)
Subject: To anybody who is interesting in science
Reply-To: marina@tk.mainet.msk.su
Organization: Moscow Aviation Institute, PDTK
Date: Tue, 28 Jul 92 13:02:04 GMT

          TO  ANYBODY  WHO IS INTERESTING IN SCIENCE
        We apply to everybody who interested in  future  Russian
science; who   would  like  to assist  it  to integrate in World
science society.
        We need information about Funds and other  organizations
who interested in  attraction russian  science organizations  to
research within  the limits active and  plan science proects and
directions of  this  researches   but also about  conditions  of
precipitation  russian scientists   in this proects.  Besides we
would like to know about questions of finance.
        We pin   our hopes on  establishment of interaction  and
development of international cooperation.
        Best regards.                 Marina V.Naumenko



Newsgroups: sci.electronics,rec.video
From: panter@micor.ocunix.on.ca (Bill Panter)
Subject: Re: Optically scanned TV (was Re: Blue Lasers)
Organization: M.B. Cormier INC., Orleans (Ont)
Date: Thu, 30 Jul 1992 04:22:50 GMT

Yesterday's Globe & Mail sites a report in Yomiuri Shimbun as reporting
that Sony had a solid state diode laser operating in the 467-483nm range.
This was constructed of "a sandwich of selenic zinc, selenic sulphide of
zinc, and magnesium".  No comment was made on low temperature operation
in the  Globe's article.

Bill Panter (panter@micor.ocunix.on.ca)
From: HARVEY@SLACVM.SLAC.STANFORD.EDU
Newsgroups: sci.electronics
Subject: Zapper
Date: 24 Jul 92 18:42:06 GMT
Organization: Stanford Linear Accelerator Center

There was a file posted some time ago for a circuit which would allow
you to control your remote controls from your PC. It was called the
Xanadu Zapper. Any help locating the file would be appreciated.


Harold
Harvey@slacvm.slac.stanford.edu
Newsgroups: sci.electronics,rec.audio,alt.folklore.computers
From: mark@phineasjpl.nasa.gov (Mark R. Rubin)
Subject: Re: Two-sided CD's *DO* exist! (was Re: Life after CDs)
Organization: Jet Propulsion Laboratory (NASA)
Date: Tue, 28 Jul 1992 17:48:02 GMT

  > [various discussions of "three-sided", and other multiply-grooved
    LP's, deleted]

o When I was a little kid, we had a record (probably a 78) containing
  a cowboy "radio drama".  It must have had grooves that split and
  re-combined, because each time we played it the plot would be a
  little different.  Things like the good guys would sometimes "head
  'em off at the pass", but on other listenings they'd go back to
  town to gather a posse.  Not surprisingly, as we played it over and
  over, some sub-plots disappeared, never to be heard again.  The
  needle had worn a path to one side of a groove split or the other.



MARK
mark@jpl-devvax.jpl.nasa.gov
Newsgroups: sci.electronics