I am back to working on this game after a long needed break from it's frustrations.
I am pretty certain that the power supply is in order now. I am getting the proper voltages but when I turn on the game I still get almost nothing. GI comes on, no displays, some solenoid resetting very briefly, then a random pop or click from the speakers from time to time. Otherwise nothing else. Using a logic probe it appears there is action happening but all I did was make sure there was activity. The LED on the MPU is solid on.
I have two MPU boards. One it came with and one NOS. I have the ROM it came with and one I burned. I have tried both boards and both roms in all combinations. The result is almost exactly the same with the exception of some configs produce a millisecond of what sounds like game audio when you start it up. And one config there is no solenoid reset at all.
I have spent so long on this game, so have a couple friends that came over to help. Today I had a pinball repair pro come over to try his hand. He had no experience with Alvin G so we were starting from the ground up. Any links, videos, info would be appreciated. I actually have zero ideas of what to try next and the lack of info on these games online is proving to be the biggest barrier. I do have the schematics.