MRB and PPB playfield power boards
Laser War has a 50 V coil board. Secret Service alone uses the MRB 520-5015-00 with a separate 50 V supply and no TIP36c anywhere. The PPB 520-5021-00 (six fuses, five TIP36c) covers Torpedo Alley to Jurassic Park; the 520-5021-05 (nine fuses) covers late Jurassic Park to Batman Forever. PPBs work in older PPB games but not in MRB games.
Systems
Related tips
- Jurassic Park can have either PPB
- What the PPB/MRB board carries
- Check PPB solder joints: the board runs hot
- Solenoid driver transistor positions on the CPU and PPB boards
- 50 V coils use PPB TIP36c transistors, pre-driven from the CPU board
- Random coils fire instead of flashers with a new driver board: relay has the wrong coil
- Three-stage drive for 50 V coils
- How a coil or flasher is switched: PIA to TTL to pre-driver to driver
Source: Repairing DataEast 1987 (Laser War) to Sega 1995 (Batman Forever), Part One, Clay Harrell (pinrepair.com)