I never planned on repairing this PCB.. I’d never even heard of it actually. But an arcade customer asked me to take a look and see if I could get it working correctly.. So why not…

Kung Fu Master has a unique pinout an needed a bench adapter made. I keep the wires and heat shrink loose until I’ve fully verified functionality..

Board #1 – In for repair

The original reported issue was that the sprites repeated..

Seemed like it should not be too difficult to find, however.. after being powered up for a short period of time..

The game de-volved to garbage.. It took a while to find this issue..

The schematics were not easy to read.. I eventually found a bad enable line that traced back to 74LS153@1B.. I was back to the stacked sprites!

Last one was a bad 74LS00@2 D/E on the video board causing the sprite stack. The board got all of the standard chip clean/burn in testing..

All of this took quite a while since it was a net new board with not the greatest documentation.. Board works!