***UPDATE: Re-seating all the connectors on the MPU cleared up the problem. I should've pulled them one at a time so help isolate where the issue was actually coming from, but I got overzealous. Marking thread Solved; will post a new thread when I run into my next issue.***
Hey all! I have this super cool Bally Black Belt, one of the infamous Bally 6803 games, that I've been trying to get going. I finally finished all the cosmetics (seriously, I tore it down in December 2018 and just this weekend finished putting it back together), resolved a number of other mechanical issues, and now need to start troubleshooting the hard stuff.
Over the time I've had the game, I've been able to turn it on, it boots up fine, the lights go into attract mode, etc. Even starting a game, it seemed to be behaving fine. However, it's starting to lose its mind.
A while back, the coil for the center saucer started locking on. I disconnected it so it wouldn't kill the coil, vowing to come back to it later. (I didn't notice any transistors LOOKING bad, but I'm going to look at the schematics to pinpoint the right one to take a closer look. Just wanted to get this posted first to deal with the more immediate problem. Read on...)
Then, more recently, the cube relay on the "solenoid expander" board -- the tiny little board under the playfield with the light right next to it (see picture below) -- started acting up, clicking on & off frenetically, basically going nuts. Now, if I start a game, almost all the PF insert lights come on (see video below), which clearly is not supposed to happen!
I'm not really sure where to start here, though clearly I'm suspicious of that relay and/or whatever's triggering it. Any guidance would be appreciated. Note, I have the manual and schematics, so hopefully that'll help us all along the way. I'll do my best to be prompt in my responses.
The video of it going bonkers:
The little relay board:
20200503_163734 (resized).jpg
The schematic for the little board:
20200503_174112 (resized).jpg
Thanks again, looking forward to getting this thing running, especially now that I've got it all put back together. This looks super fun!