Tonight I am working to bring an old Bally -35 back to life. I intended to just have this be a spare board to have for the next project, as it didn't look too tore up by alkaline damage.
So here is my issue. When I have this board on bench it boots up fine. When I put board in game known good game it boots fine. But after it boots it dose not seem to function it attract. Stuff on game seems slow or just stops. I have had this issues on boards before with bad jumpers settings or a break in jumpers. I have checked and verified that is not issue. Other issue is that the it is causing solonoid Q9 to fire repeatedly. Seems to just fire in sync in one second pulses.
So here is what I have done.
Replaced all header pins
Replaced U2 socket
Installed new PIA in U10 and U11
Replaced bad diode at CR41
Using know good game Roms at U2 and U6
Guess the next step is to trace back that solenoid strobe to U10 and see if I have a resistive short??? Or just replace the socket?