Diode-test the PMD10K40/2N6057/2N6059 on the pop board or power supply

Steps

• Meter on diode test.
• Black lead on the transistor case (on the pop board, the bottom mounting screw).
• Red lead on each leg in turn: each should read 0.4 to 0.6, otherwise the transistor is bad.

Systems

• Gottlieb System 80
• Gottlieb System 80A
• Gottlieb System 80B

Related tips

• Use a TIP102 in place of the pop bumper board's 2N6057
• Add power and fire LEDs to a pop bumper driver board
• How the System 80 pop bumper driver board works
• A pop bumper doesn't work at all
• Bench check of a pop bumper driver board
• Pop bumper board wiring is in each game manual
• Common failures on the pop bumper driver board
• Has the pop bumper board factory fix been done?

Source: Repairing & Upgrading Gottlieb System 80 Pinballs from 1980 to 1989, Part One, Clay Harrell (pinrepair.com)