[comp.sys.mac.hardware] Apple Monitor RGB Monitor Problems

frel@randvax.UUCP (Dave Frelinger) (01/15/90)

I have been having a real problem with my Apple RGB Monitor.  The image is
ustable, jumping a little in the horizontal.  The real problem is its
intermittent nature, and its nasty habbit of never appearing when the
technician is working on the monitor.  I have tried to have this fixed by
replacing the analog board in the monitor, but that didn't seem to fix the
problem.  Has anyone else had this problem?  Is this consistent with a
problem with the monitor's power supply?

		Dave

jong@k.gp.cs.cmu.edu (Jon Gotow) (01/16/90)

"frel@randvax.UUCP (Dave Frelinger)" writes:
>I have been having a real problem with my Apple RGB Monitor.  The image is
>ustable, jumping a little in the horizontal.  The real problem is its
>intermittent nature, and its nasty habbit of never appearing when the
>technician is working on the monitor.  

I know this may sound stupid, but try moving the video cable.  I had this 
same problem, and after much worrying about the horizontal deflection 
circuitry dying, I was messing around behind my Mac when the problem 
suddenly went away.  I had one of those little plug-in transformers 
for my modem sitting right next to the video cable - it seems to have 
been generating enough interference to disrupt the video signal slightly.  
Moving the cable closer caused the problem to reappear, relocating the 
transformer solved the jitter altogether.  Hope your problem's that 
simple!

				Jon

Jon K. Gotow		Research Engineer
The Robotics Institute	Carnegie Mellon University.
jong@k.gp.cs.cmu.edu

CMU has nothing to do with anything I say - they seldom acknowledge that
I even exist.