I picked up a used Mk2a and it has a problem. When I first powered up the unit the display looked fine, but after warming up for a half hour or so, the display is smeared side to side. And now, it is completely blank with nothing on it at all.

I checked the suspect fuse on the main board and it is fine. I even took the display board from the my other empeg and it also works fine. So it's something on the display itself.

I suspect that there is something wrong with the PIC chips. Any ideas on where I should start looking with the scope?