Testing the 2N6043 coil drivers
Steps
- These are Q25 (knocker), Q26-Q28 (sounds or chimes), Q32 (outhole) and Q30/Q31 (game coils); they read the same in or out of circuit.
- Meter on diode test, component side: black lead on the centre lead, red on each outer lead in turn.
- Each should read 0.4 to 0.6; anything else means the transistor is bad.
- Replace a bad 2N6043 or SE9300 with a TIP102.
Systems
Related tips
- TIP102 is a good substitute for SE9302 coil drivers
- 20-second test for shorted coil driver transistors
- Where the WPC coil and lamp drivers sit
- How a WPC coil, flasher or lamp driver chain works
- How many coils the driver board can fire
- Which driver transistor fires which coil
- The 19 solenoid driver transistors
- Solenoid driver transistor types
Source: Gottlieb System 1 Pinball Repair from 1977 to 1980, Clay Harrell (pinrepair.com)