I bought this faulty Point Blank PCB for cheap on Ebay:
Seller said it had graphical corruption and was missing a primary color and sound.When I powered it up I actually had sound but the other two issues were there:
The missing color was the green, tracing the pin 12 solderside back from JAMMA connector I found the culprit : one of the three SMD transistor ( each of which drives a color output) was missing:
Green was so restored :
but graphical troubles were still there.Inspecting the board I found that some pins of the custom C355 were smashed:
This custom handles the motion objects (sprites) and my issue concerned this part of graphics.Having a spare Namco NB-1 board I opted for a replacement of this ASIC :
After some work and pads rebuilding, I ended up with this result:
In this way graphics were completely restored but sprites had jailbairs:
Pressing down the board fixed the issue temporarily, inspecting again the board revealed a liften pin on a TC51832 (62256 compatible)RAM @12R:
Resoldered the pin and board 100% fixed.
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