I have a Kiki KaiKai (also called Wonder Boy) that has lost the green color. Other PCBs show all colors so it is not the Jamma harness och monitor.
I have taken care to position the Jamma connector aligned and have also cleaned the connectors.
The connector for the green color is ok as far as I can trace it. It passes a resistor that is ok and then connects to an DM74S287AN, leg 9.
The color where first ok on the PCB for a couple of months. Then it started to show some problems now and then with the colors. Now the green is gone. All other function is ok and it plays as it should. No sprite error.
Any ideas where to begin?