A year ago I picked up a broken Capcom 1942 board for 10USD. The board was in pretty bad shape, but I thought it would be a good challenge. The nice thing about this game is that it’s built using mostly 74LS logic. The odds are then a lot better than dealing with boards packed with custom ASICs that you can’t get unless you have another donor board. However, the board stayed in the closet until now.
The Capcom 1942 was released in 1984 and it was released before the Jamma connector had been adopted by most vendors. To make this game Jamma compatible someone had gotten the bright idea to solder wires directly to the connector! The first step was to remove this and clean the connector before attaching a good quality PCB converter.
This was actually more work than I thought. The old flux stains were hard to remove with alcohol but after a half-hour of work the connector looked almost like new 🙂 It was time to power up the board and see what we were dealing with. The board booted just fine, but the joysticks+coin inputs didn’t seem to work. There was also no sound. I followed the coin input from the edge connector to a strange looking 74LS367. The top was all scratchy and looked worn.
The LS367 surely didn’t pass the test. Two of the units where not working. Those units were connected to the Coin 1P+2P so it was obvious why it didn’t work. I replaced it with a new one.
The audio amplifier section on the board also looked like a war-zone. One capacitor had been twisted so hard that the legs had been pulled out of the board. I replaced it with a new one.
I powered on the board and everything was working perfectly! Mission accomplished!