How the System 80 pop bumper driver board works
Each pop bumper has its own one-shot board under the playfield. The skirt switch grounds PBDB pin 4 to logic ground, and the board pulses the coil once for a fixed time even if the switch stays closed, so a misadjusted skirt can't lock the coil on. A second switch on the bumper, closed as the coil fires, goes to the CPU switch matrix and only scores.
Systems
Related tips
- Bench check of a pop bumper driver board
- Common failures on the pop bumper driver board
- Mandatory pop bumper driver board update
- How the pop bumper driver board fires its coil
- Snappier pops: the System 80B pop bumper board values
- Using a pop bumper driver board as a timer for motors and toys
- Original pop bumper driver board values (A-19741)
- Add power and fire LEDs to a pop bumper driver board
Source: Repairing & Upgrading Gottlieb System 80 Pinballs from 1980 to 1989, Part One, Clay Harrell (pinrepair.com)