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Commodore 64 breadbin with a black screen
Power LED on, nothing on screen. A failed PLA, plus a full recap while it was open.
Sample Sample content, to be replaced before launch.
What came in
A 1983 breadbin, board revision 326298. Power LED on, black screen, no sound. The owner had been using the original power supply.
What we found
The original supply measured 5.4 V on the 5 V line, inside the safe limit but climbing under load. With a modern supply and a diagnostic cartridge, the machine still showed a black screen. The PLA was running hot and failed the logic probe test.
What we did
- Replaced the PLA with a modern replacement, on a new socket
- Replaced every electrolytic capacitor on the board
- Cleaned the keyboard connector and the expansion port
- Ran the 4-hour burn-in with the diagnostic cartridge looping
Before you plug it in
The original power supply went back with the machine, cut and labelled. Original C64 supplies can fail by sending too much voltage, which destroys the chips we just replaced.