Repair 1991 Williams Party Zone

This machine is on location now up at Hoots Beer Co. in Winston-Salem, so head on over and put some quarters in!

The primary functional issues with this game were: missing one entire column, several other switches not registering, Captain Bizarre was spinning continuously and after all those issues were taken care of the F102 right flipper fuse was blowing.

Installed opto board on Captain Bizarre with all new optos.

Installed opto board on Captain Bizarre with all new optos.

The Captain Bizarre toy communicates between the CPU with 3 opto switches on a small under playfield board. This board was completely missing one of the optos and only one of the other two was functioning correctly. Since I had to order the one, I decided to replace all 3 on the little board.

A lot of times an entire missing column leads to the replacement of the often-failed 2803 chip at U20 on the CPU. However, you never want to rush to replace an IC chip as the delicate through-holes on these boards can be easily damaged. I isolated the problem to the CPU, then used the schematic to buzz back the traces from the pins to the CPU to make sure a simple jumper wasn’t a solution to the problem. When everything buzzed out and that column was still failing the switch test, I then replaced the U20 chip with a new chip and socket for easy replacement later if the new chip ever fails. That, in this instance, was the culprit and that missing switch column returned to working order.

Socketed new U20 for missing switch column issue.

Socketed new U20 for missing switch column issue.

All of the unregistering switches were adjustment issues. The blowing flipper fuse at F102 was a maladjusted EOS switch on the right flipper. It was staying high power all the time and never switching over to low power, causing the flipper to blow on hold.

Advertisement

About Matthew Mandarano

Matthew is a cinematographer and video specialist by day and pinball fanatic at night. Somewhere in between he also finds time to play the guitar, collect vinyl records and watch a good deal of movies and TV shows.
This entry was posted in Repairs and tagged , , , , , , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s