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Article #7860

Re: IBM EGA monitor failure

#7860
From: Lon Stowell
Date: Thu, 18 Oct 1990 21:34
52 lines
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In article <60129@bbn.BBN.COM> sher@BBN.COM (Lawrence D. Sher) writes:
>I have an IBM "Enhanced Color Display" EGA monitor, type 5154..
>Symptoms:
>
>1. When first turned on, the background brightness is unusually high
>and the vertical height is too.  Both recover to normal during
>5-10 minutes of warm-up.


Hard to say, but if the display is blooming, your high voltage
circuit is likely tweaked....if just vertical, this may be the
vertical sync/drive cktry.

>
>2. Failure takes one or both of two forms, both after some warm-up:
>
>   (a) The raster splits near the center of the picture, creating a
>   mostly blank horizontal stripe across the center.

Your vertical sync just went south.  The stripe is likely the
vertical blanking interval.  This can have two causes,,,,,if the
vertical SIZE is to much, the vertical Hold won't be able to
keep the picture stable.  This sounds more likely than simple
loss of Vertical Hold which would cause continuous rolling.
Given Fault #1, vertical drive components are suspect OR the
high voltage.
>
>   (b) A generalized raster degradation takes place in which the
>   characters are just recognizable but poorly formed.

Do the characters smear horizontally or vertically? If vertical,
still sounds like vertical.....

>
>   There is an accompanying smell, like of an electrically overheated 
>   component.
>
Have you opened the unit (or will this void any warranty).  You
might just get lucky and spot an obviously abused component.   

Repair cost is REAL close to our local (very competitive)
pricing on a NEC Multisync......or a Mitsubishi Diamond Scan...
I know what I would do.....donate the old unit to the local
electronics division of a college, etc.  Buy the NEC or Mitsu...


            /|
	\'o.O'
	=(___)=
	   U

     THPTH! ACKHH!
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!mips!prls!pyramid!lstowell
From: lstowell@pyrnova.pyramid.com (Lon Stowell)
Newsgroups: sci.electronics
Subject: Re: IBM EGA monitor failure
Message-ID: <130932@pyramid.pyramid.com>
Date: 18 Oct 90 21:34:20 GMT
Sender: daemon@pyramid.pyramid.com
Reply-To: lstowell@pyrnova.pyramid.com (Lon Stowell)
Distribution: na
Organization: Pyramid Technology Corp., Mountain View, CA
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