The Solid State Relay board switches the backbox lamp

Some 6803 games light the backbox with one incandescent bulb that is switched on and off for effects by a little Solid State Relay board mounted in the backbox (Dungeons & Dragons uses A084-91880-A000). If the backbox light never comes on, check that board along with the bulb.

Systems

• Bally 6803

Games

• Dungeons & Dragons
• Motordome

Related tips

• Swap a hot incandescent backbox lamp for fluorescent
• Some feature lamps out after the backbox was lowered
• How the CPU keeps lamp phases in step
• Lamp tests: phases and single lamps
• Lamp driver SCRs on the CPU board
• Keypad keys are switch matrix crossings
• How 6803 feature lamps share SCR drivers
• None of the CPU-controlled lamps light

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