eMac Display Issue

CBM1084

New Tinkerer
May 13, 2024
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Hello,

I recently purchased an eMac on ebay that was listed as "in great working condition", but when it arrived it was in fact not working properly. The computer itself seems to work fine but the display is completely distorted, shifting and flickering constantly so with half the picture off the bottom. From my understanding, the capacitors in these eMacs can often be a problem, but I'm wondering if anyone has any information on which components in particular might be at fault here. I haven't been able to locate any schematics or specific information about the anolog board in this machine. I'm hoping someone might be able to point me in the right direction with this repair.
Here's a clip of what it's doing:

The main question of course is whether this is something that is reasonable enough to fix, or if I should just return the computer. I'd rather not ship it again if I can avoid it, but if fixing it will prove more trouble than it's worth I may have to. I'm comfortable enough working around the CRT but without any details about the electronics and what specifically might contribute to this problem, I don't really know where to start.

This eMac is a 1.25 GHz model with 256 MB of RAM.
I'd appreciate any help trying to solve this.
 

xcmd

New Tinkerer
Dec 24, 2024
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Check the video cable, having bad raster like that is one of the symptoms I think. A popular work around was to shield the cable better (such as wrapping foil, but but being certain to ground one side and ensure it's not shorting anything, a insulating material around the foil would be better) or adjust the routing. While in there, check the caps, many emacs had the worst capacitors in them of the 2000s.