My WCS has an intermittent problem with the DMD display. Basically, when there's a fast animation, the display shows the wrong frame some of the time. One simple demonstration is to open the coin door: there should be a "coin door open high voltage disabled" type message, that flashes positive and negative a few times (ie, amber text on black background, then black text on amber). Usually (say 3 out of 4 attempts), instead the display will flash one of these "frames" (positive or negative), along with whatever had been on the screen before or recently (say, "game over"). This also occurs during the game enough that it's difficult to see what random awards are being given often times.
I re-seated and then replaced all 4 ribbon cables with no improvement. I've tested the voltages at the DMD driver board and they all check out within the ranges on pinwiki. I poked around a little bit on the board where I could test easily (for example, BR1) and everything tested ok (though I could have easily missed something)
I swapped my WCS DMD into my other game (no good gofers) and it worked fine, so I don't think it's anything wrong with the DMD.
The HV portion of the DMD controller board looks pretty crispy, but it also has definitely been repaired at one time. For example, the big electrolytic capacitors are 220 um, which is what gpe sells in their repair kits, but not what shipped with the game. I don't know if the components on it now have gotten hot or not. The big cement resistors are spaced off of the board a bit, which makes me think the burn marks are old.
I was planning on rebuilding the HV portion of the board, but I wanted to see if anyone had any insight beforehand. I've done some circuit board repair before, but not a ton, and the fact that the board has been rebuilt already made me 1) think it might not be the HV section, and 2) reconsider if I'm up for the task.
A side question: I assume that if I screw something up and can't fix it, I can still buy a piggy-back board to fix the DMD Controller and at the very least get back to where I am now. Assuming I don't mess with anything in the top 3/4 of the board, is that a fair assumption?
Thanks in advance,