System 11 alphanumeric displays

The game has two 16-digit plasma displays, needing +5 V, +100 V and -100 V from the power supply. On earlier System 11 games the lower display shows numbers only.

The display supply runs at about +100 V and -100 V; switch off before touching the display or its driver board.

Systems

• Williams System 11
• Williams System 11A
• Williams System 11B
• Williams System 11C

Related tips

• System 9 versus System 11 display data
• Score display layouts across System 11
• Swapping Williams and Data East alphanumeric displays
• Check every segment with the display test
• UDN display driver chips
• Lower the display voltage to 91 V to extend display life
• Characters missing from a display
• Spare UDN7180 at U12 on Pinbot display boards

Source: Pinball Machines: How They Work & Troubleshooting, Norbert Snicer