Fixing a Commodore 64: Replacing a Faulty PLA Socket

189

Lee from More Fun Fixing It repaired a faulty Commodore 64 suffering from a bad PLA socket. The machine initially displayed a garbled screen, and pressing down on the socket slightly changed the display but didn’t restore functionality. A previous cleaning and reseating attempt provided only a temporary fix due to the chip’s short legs and the poor-quality single-wipe socket.

To properly fix the issue, Lee desoldered the failing socket, first adding fresh solder to make removal easier. While inspecting the board, he noticed inconsistencies in pin lengths—some were cut too short, while others were excessively long and needed trimming to prevent shorts. Once the old socket was removed, he installed a new dual-wipe socket, offering a much more secure connection for the PLA chip.

After soldering everything in place, he reinserted the PLA and powered on the machine. A full set of diagnostics, including a harness test, confirmed that everything was now working correctly. To ensure stability, he applied contact cleaner to the ports before reassembling the system. With the repair complete, the Commodore 64 was restored to full functionality, marking another successful fix on More Fun Fixing It.

Subscribe
Notify of
0 Comments
Oldest
Newest Most Voted
Inline Feedbacks
View all comments