Picked up a James Bond project and I've got it partially back to life. Working out some bugs. Suggestions welcome!
New Ni Wumpf MPU, replaced the power supply with a known working one.
* Game boots up, displays / GI on, credits up fine, knocker works. I can start a game and the ball will kick out, and the switches for scoring seem to work fine. None of the other solenoids were working, so I checked the Q (Game Over) relay. It's not pulling in when a game is started.
* I put a jumper between ground and the metal tab of transistor Q1 on the driver board, and the "Q" relay pulled in just fine, allowing the flippers and slingshots to work (pop bumpers not working still). So I know the wiring should be good from that perspective.
* I tested for voltage at the solenoids (and at the Q relay) and it's sitting around 40vdc. I thought it was supposed to be 24vdc, but I saw some references in other posts about there being 38-40vdc on the solenoid line. Is that accurate?
* Checked the rectifiers in the bottom of the cabinet and they tested around .488 using the diode tests on the System 80 repair guide, so they seem ok. The + side of the solenoid rectifier is showing 40.1vdc, the other two legs sitting right at 23.9vdc relative to the ground tab.
* I don't have sound, and I noticed that when I diode tested the Sound rectifier, I had continuity between ground side and + side... not sure if that's a problem. The other rectifiers didn't have that when I checked (I know that wasn't in the test guide).
* I cleaned the contacts on the Q and T relays. I have not repinned all the connectors yet (waiting on more bits and pieces in the mail).
Thoughts? Why wouldn't Q be pulling in?