I was working on and troubleshooting this project Gottlieb Target Alpha last night. While addressing all of the playfield switches to make sure they were registering and scoring correctly, I decided to pull the neutral wire off of the chime unit to stop it from ringing. This is something I do all of the time on my Williams games with no issues. In the case of Williams games, I just pull the chime jones plug all together.
Not putting 2+2 together quick enough, I soon found myself bewildered that none of the playfield switches were scoring anymore. I soon discovered after I reconnected the neutral wire back on the chime unit, all of the switches were back to normal.
So the question is for someone out there, why on earth is the neutral wire on the chime box associated with all of the switches on the playfield?