Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uwm.edu!uwvax!umn-d-ub!umn-cs!chou
From: chou@umn-cs.CS.UMN.EDU (Hsiang Chou)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Apple 13" Color Monitor wobbles
Message-ID: <17316@umn-cs.CS.UMN.EDU>
Date: 27 Nov 89 04:34:11 GMT
References: <445@tci.bell-atl.com> <19899@pasteur.Berkeley.EDU>
Reply-To: chou@umn-cs.cs.umn.edu (Chih-Hsiang Chou)
Distribution: comp
Organization: CSci Dept., University of Minnesota, Mpls.
Lines: 36

In article <19899@pasteur.Berkeley.EDU> korn@anableps.berkeley.edu (Peter "Arrgh" Korn) writes:
>In <445@tci.bell-atl.com>, mitchell@tci.bell-atl.com (Rob Mitchell) said:  
>>
>>	The whole image on my Color Monitor wobbles.  It acts as though
>>there may be a magnetic field around, but there isn't....
>>
>>	Any ideas?
>
>There is a known problem with Apple Color monitors within a certain
>serial number range of early serial numbers that exhibit this problem.
>......

	Can you mail me or post the serial number range?
>.....
>that I haven't bothered.  Instead, however, my monitor will no longer
>show a true black and has a faint border around the actual image on the
>screen (as if the brightness were up too high except it's not).  Lacking
>time, I haven't pushed hard on any of the local dealers to fix it.
>
	I had a similar problem as yours. My screen won't turn black
in the image area even when I turned the brightness and contrast all
the way down, although the border is always black.

	I fixed this problem by turning an undocumented knob on the
back of the Apple color monitor. It's located at the top of a column
of knobs (under a hood) including Horizontal and Vertical Sync. You
can find this place from your monitor's manual. However, no documentation
is given for this knob which has an icon of the sun (i.e. brightness,
I guess).  I simply turned the knob in one direction, then I got the
screen to show true black. The only caveat is that the ranges of the
user adjustable brightness and contrast become shorter than before.

-- 
Chih-Hsiang Chou	chou@umn-cs.cs.umn.edu
Department of Computer Science
University of Minnesota