Williams System 8

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Click to go back to the Williams solid state repair guides index.

1 Introduction

Williams System 8 Board Set



The Williams System 8 boardset was used in 1984 with only two games, the pitch and bat Pennant Fever and Still Crazy, a novelty game. Combining the driver board, sound board, and cpu directly onto one board eliminated several design deficiencies of the earlier System 3-7 boardsets; mainly the 40 pin interconnector, and extra wiring harness interboard connectors.

System 8 is very similar to its successor (System 9), but it is more of a "slimmed down" version. There are a total of 8 controlled solenoids versus the 16 used with the system 9 boardset. Another distinct difference is system 8 hardware does not utilize special solenoids. System 8 also lacks the connector for a speech daughterboard.

Although system 8 is capable of driving four 7-digit displays and one 4 digit display, only two 7-digit displays are used with Pennant Fever and one 7-digit display is used with Still Crazy. Therefore, master display boards are not used on either game. Both the lamp and switch matrices are 8 x 8 in size, but neither Pennant Fever nor Still Crazy use many switches in their matrices.

2 Games

Title Date of Release Model # Other Boards Notes
Pennant Fever 05-1984 526


3 Technical Info

3.1 CPU Driver Board

System 8 CPU


3.2 Power Supply

System 8 Power Supply


4 Problems and Solutions

4.1 Power Problems

4.2 MPU boot issues

4.2.1 Relocating the battery from the MPU board

4.2.2 Repairing Alkaline Corrosion

Remove the battery holder entirely from the MPU board and wash the board's affected areas with a 50/50 mix of vinegar and water. Scrub the corrosion with a soft toothbrush, rinse with water, then rinse with 91% or 99% isopropyl alcohol to displace the water.

4.2.3 Connecting a logic probe to the MPU

4.2.4 Using a PC Power Supply For Bench Testing

4.3 Game resets

4.4 Solenoid problems

this is a stub


4.5 Lamp problems

4.5.1 Lamp Matrix Row and Column Testing

4.6 Switch problems

4.6.1 Switch Matrix Row and Column Testing

4.7 Display problems

WARNING: This circuit uses high voltages. Don't continue, unless you are confident in your diagnostic abilities.

4.8 Sound problems

5 Repair Logs

Did you do a repair? Log it here as a possible solution for others.