Punch out graphic help needed

MattGnSC

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I picked up a punch out that has a graphics issue with the upper/ opponent monitor. On the attract screen that reads "punch out" it seems fine but any other graphics are garbled. Ive cleaned and reseated all of the seated chips on all 3 boards. I've swapped video inputs between the monitors and the problem follows. I'm thinking it's a graphics rom chip but I don't know how to troubleshoot further. I'll try to upload pictures soon. Does anyone have any other suggestions?
 

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Most likely an issue with the character/sprite section of the BAK PCB (smaller of the 3).

Now who here repairs PO boards?...(wink wink) ;)
 
Most likely an issue with the character/sprite section of the BAK PCB (smaller of the 3).

Now who here repairs PO boards?...(wink wink) ;)

If you know somebody with that pcb (BAK PCB) you could swap it in to make certain it is the problem. Nothing worse than sending a board off to be repaired and it works perfectly.
 
If you know somebody with that pcb (BAK PCB) you could swap it in to make certain it is the problem. Nothing worse than sending a board off to be repaired and it works perfectly.

All of the logic for the top screen in on the BAK PCB. The video PCB (middle PCB) handles challenger (player) sprites and champion (opponent) sprites. BAK PCB handles character logic and color selection for the bottom PCB, and character/color logic for the top PCB.

But yes if he can gets his hands on a known working BAK PCB he may be able to trade out ROMs etc in case it's an issue with one of the upper screen character ROMs.
 
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