Updating pre-Ice Fever reset boards to protect RAM Z5

Steps

• Work on the 40-pin plug of the reset board that goes into the CPU board.
• Fit a 3K 1/4 W resistor between pins 7 and 11.
• Fit a 1N4001 diode between pins 17 and 24, banded end to pin 24.

Systems

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

Related tips

• Fit a remote battery holder
• A single lamp does not light
• What the System 80 reset (watchdog) board does
• How the control board reset circuit works
• Replace the System 80 reset circuit with a DS1811 chip
• DS1811 reset chip threshold versions

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