Hi,
I have brought a 4 Square back to life after decades of storage and neglect. I had it playing fine for a 2 weeks, but today the Alternating Relay was locked on. Hitting the pop bumpers and slings did not turn it off though they scored as normal (one point) Examining the schematics suggests that the issue may be in the "0-9" Unit which I am not familiar with. I assume it is on the ones score reel. Examining that reel yielded no obvious issue. Any tips to get this issue sorted out?