I recently acquired a home use FP purchased new in 1981. The boards look almost new (seen here https://pinside.com/pinball/forum/topic/the-firepower-club/page/24#post-3608170 ) . After a good cleaning, conversion to LEDs and some touch ups, it plays just fine.
However, after about 30 minutes in attract mode it will start playing sounds, randomly placing numbers in the player 1 display and will ultimately blow the F2 solenoid fuse.
I can play for hours with out this happening. It only happens when I leave it alone in attract mode.
Besides the obvious "turn it off after playing" solution, does anyone have an idea what might be going on. It seems like it could be temperature related but I can't figure out why it only happens in attract mode.
I haven't touched the boards to "bullet proof" them. Perhaps its time.
Any assistance will be greatly appreciated.