Finally had a chance to plug both of these boards on my bench and see if everything is working before I plug it into my game.

Game booted up fine, but could tell initial there were problems with the lamps.  Only one row (or column) was lit and nothing else was working on it.  I tested the switch matrix and all switches are working correctly.  The solenoids all worked, but the special solenoids had three solenoids that were stuck on.

I decided to trouble shoot the light matrix first.  Since the PIAs were all the AMI type, I started there and replaced IC10.  This fixed the lamp problem.

I switched out the PIA for the solenoid and solenoids were still locked on.  I traced back to IC9 (7402) and noticed that the outputs were stuck on about 2.5V and should have been low since both inputs were high.  Replaced the IC and the solenoids were working; however, the relay would kick off after it cycled the 25 steps.  Switched back to the original PIA and now everything works as it should!


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