Fit a remote AA battery pack to a System 80 CPU board

Steps

• Remove the original battery.
• Wire a three-AA holder off the board, with a 1N4001 or 1N4004 diode in the positive lead: banded end to the board's "+" pad, unbanded end to the pack's positive wire, so the board does not try to charge the alkalines.
• Connect the pack negative to the negative pad.
• With the game off and the batteries fitted, check for battery voltage on the 5101 RAM Z5 pin 22 against ground to confirm it is wired right.

Systems

• Gottlieb System 80
• Gottlieb System 80A
• Gottlieb System 80B

Related tips

• Replacing the CPU battery with a remote AA pack
• System 80 switch matrix diodes
• Fitting a remote battery holder to a WPC CPU board
• Fitting a remote battery holder
• Clean up battery corrosion on a System 80 CPU board
• Parts typically ruined by battery leakage on a System 80 CPU board
• Where the battery-area parts sit on the System 80 CPU board
• Move the CPU batteries off the board

Source: Repairing & Upgrading Gottlieb System 80 Pinballs from 1980 to 1989, Part One, Clay Harrell (pinrepair.com)