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From: torch@attctc.Dallas.TX.US (Jay Finger)
Newsgroups: comp.sys.mac.hardware,comp.sys.mac
Subject: HELP: Mac 512K Video Problems
Keywords: video broke bad repair analog
Message-ID: <11248@attctc.Dallas.TX.US>
Date: 31 Jan 90 23:18:48 GMT
Followup-To: comp.sys.mac.hardware
Organization: The Unix(R) Connection, Dallas, Texas
Lines: 36

I know this same type of question has probably been answered eleventy zillion
times, but I didn't pay attention to them then...

I've got a 512KE (which started life as a 128 back in Dec 84!).  Every now
and then the right edge of the screen will flicker/vibrate/shake (I'm not
sure how to describe this) rapidly.  Sometimes it's the entire screen
at once, other times it does it so fast that each scan line gets a
different amount of distortion so it looks like there's some noise in the
video.

This usually happens for about 10 seconds, and then stops.  It might start
doing it again a few minutes later, or a few days later.  For a very long
time it appeared that it had no correlation to how long the computer had
been turned on (i.e. not a thermal problem).  It's been doing this for about
two months, but until recently it wasn't bad enough to make me get off
my a.. and look for help/advice.  But for the past couple of days it has
been fairly consistent in doing it for a couple of minutes when the computer
is first turned on, and then after it's been on for a while the problem
shows up more often.

Can somebody please tell me what needs to be done to get this fixed?  What
do I need to do to fix it myself, and if I do it myself what kind of
problems will I have later on if I actually need to get the video/analog/p.s.
board replaced?.  I'm quite handy with a screwdriver and soldering iron, and
know the difference between a resistor and cap, etc, etc, etc.  But I've
never done any work around CRTs before, so I'll need a good description of
what needs to be discharged, and the best ways to go about discharging
(i.e. a resistor to bleed the charge off, or the blade of a screwdriver :-).
Also, advice on where to get the parts (if someplace other than the corner
Radio Shack).

Many thanks in advance,

Jay Finger,
{ames,mit-eddie}!attctc!torch
ames!torch@attctc