I picked up a nice looking Airborne Avenger and I'm having a problem with the 90 volts on the old score display. With the power cable unplugged from the score display, the match/credit display works correctly. When the power cable is plugged in to the score display board, neither of the displays work. It seems that something on the score display board is pulling the voltage down, but I can't figure out what it is. Anyone have any ideas? Thanks!