Testing a driver board with a Ni-Wumpf CPU

A Ni-Wumpf CPU board can cycle lamps and coils (including the Q and T relays) continuously, tests the four-digit display and shows switches quickly, which makes it a good tool for testing a driver board and playfield.

Systems

• Gottlieb System 1

Related tips

• The CPU to driver board harness
• Testing a CPU lamp circuit by grounding its driver
• System 1 CPU board connectors
• Aftermarket System 1 CPU boards
• System 1 driver board connectors
• CPU connectors that fail most
• Testing the 2N6043 coil drivers
• Early driver boards lack isolation diodes

Source: Gottlieb System 1 Pinball Repair from 1977 to 1980, Clay Harrell (pinrepair.com)