Display driver board versions
The display driver board (behind the backglass on System 3-6, on the back of the display panel on System 7) also runs the credit and ball-in-play display. There are chip versions (UDN6184A/UDN7180A, or 22-pin NE584/NE585) and a discrete-transistor version made around Flash to Firepower; all versions work in all games.
Systems
Related tips
- Score display driver chip substitutes
- Master display board versions
- UDN display driver chips
- Upgrade R2/R5 and check R1/R4 in the display supply
- Which UDN6184 drives which display
- Chips that commonly fail on System 3-7 boards
- All score displays dead
- Using a logic probe on the display board safely
Source: Repairing Williams System 3 to System 7 Pinball 1977 to 1984, Part One, Clay Harrell (pinrepair.com)