Electronic spares for 6803 board repair

For the lamp matrix stock 2N5060 SCRs (2N5062 also works) and MCR106-1 / T106 SCRs (NTE5411). For coils stock TIP102 drivers and CA3081 (NTE916) pre-driver arrays. Also keep 1N4004 and 1N4148/1N914 diodes, an 11,000 mfd axial filter cap, a 6803 CPU, several 6821 PIAs (68A21 and 68B21 also work), a 6116 RAM and machine-pin SIP sockets.

Systems

• Bally 6803

Related tips

• What is on the 6803 CPU board
• Cybernaut can have a -35, 6802 or 6803 boardset
• Bench-test a CPU board with the 6803 test EPROM
• Power a 6803 CPU board on the bench with a PC supply
• Jumpers JW8-JW11 for the spare driver circuits
• Check the 6803 clock at U1 pins 2 and 3
• Find a bad 6803 or a shorted bus line
• CPU board landmarks: battery, LED, relay and ROMs

Source: Repairing Bally 6803 Pinball Games from 1985 to 1989, Clay Harrell (pinrepair.com)