My brother asked me to post this for him. He's in the process of reviving a Bally "Star Trek" game (original version).
"I have a strange problem with my Bally Star Trek. The game will not boot up if the sound board is connected. I get 6 pulses from the MPU board. On the 5th pulse, I get a blip from the sound board but then nothing. If I disconnect the large connector to the sound board, the game will boot up normally. I can then plug the sound board back in and it works normally. What if anything do I have to replace on the sound board?"
The game has an Alltek replacement MPU board, and he has repinned many, if not all the connectors.