If your Bally early solid state solenoid voltage is low--(symptoms: weak
flipper, bumpers, and kickers), first check your connections to the power
supply. The Molex type connectors (female pins) are one possible cause.
Another is the board-side connector male pins may need the solder reflowed
because the heating/cooling cycles may have caused cracking in the solder
joint. Also check the solenoid bridge rectifier--BR3. It may have the same
solder joint problems and the connectors. Reflowing the solder should solve
the problem. There are other possible causes for this problem, but these
are the most common causes by far.