Game Over (Q) and Tilt (T) relays are not fused
The power distribution drawing notes that the Game Over (Q) and Tilt (T) relays are not fused, and that every coil and coin counter uses a 1N4004 diode across it. When replacing a coil diode, use a 1N4004 and fit it the same way round.
Systems
Related tips
- Check every coil's resistance before first power-up
- Burnt H, Q and U continuous-duty relays on 1975+ Gottlieb
- Testing the diode on a coil
- Wire an A-16890 relay coil to run on EM AC power
- Coil diode and wire orientation when replacing a coil
- Replace SE9302 drivers with TIP102, and renew the parts around them
- No score displays light at all
- Rebuild the solenoid driver board high-voltage section
Source: System 80 Service Manual, Gottlieb