What is on the System 1 bottom panel

The lower cabinet panel holds both power transformers, the main fuses, the copper ground strip where all grounds meet, the line filter with a 120 V service outlet, a four-diode bank serving the coin door switches, plus one bridge rectifier for the 24 V coils and one for the 6 V CPU lamps.

The bottom panel carries 120 volt line power; unplug the game before touching the transformers, line filter or fuse block.

Systems

• Gottlieb System 1

Related tips

• Bottom panel fuses on System 1
• Testing a bottom panel bridge rectifier
• The two System 1 transformers
• How power reaches a System 1 game
• Spare diodes, capacitors and other parts for System 1
• Replacement bridge rectifiers
• Coil, CPU lamp and GI supplies
• Power supply bring-up, step 1: inputs

Source: Gottlieb System 1 Pinball Repair from 1977 to 1980, Clay Harrell (pinrepair.com)