The problems associated with the original Gottlieb driver board are four-fold - connections to the CPU can be corroded and cause poor driver/lamp signals; the MPS-U45 is a very difficult transistor to find; the old 2N3055 transistors burned holes through the PCB, and a failed driver board will cause as much damage to a sound board as a failed sound board would do in reverse. Ni-Wumpf has redesigned the System 80 driver board to address all these issues, and adds in a few more features that should prove useful:

  • Each solenoid has fault detection circuitry that identifies failed playfield/driver board components
  • FET solenoid transistors
  • Higher rated transistor components for all circuits
  • Discrete components for easier/less-expensive service repair in the future. Using a transistor array is neat, but costly, when one lamp in the array fails!
  • Open-collector interface to the sound board to buffer against failures generated to/from that source
  • Modern component architecture uses currently available parts for easy field service - only parts that do not normally fail are surface mounted
  • Diode isolated grounds to prevent playfield lamp problems from the board

Each driver circuit is equipped with fault detection circuitry and LED's to indicate circuit failure.


Note that the LED will remain lit when a game does not support the associated playfield driver components.

Driver Circuit