In this latest video, Chicken 64 tackles a faulty PLA repair on a Commodore 64 that’s been sitting in his collection with a dreaded black screen. Using classic troubleshooting methods, he brings a lifeless 250425 board back to life, proving that patience, precision, and a bit of humor go a long way in retro repair.
After confirming the C64 produces only a black screen despite valid video sync, Chicken 64 begins his diagnostic sequence. The death test yields no result, pointing to the usual suspects—PLA, CPU, VIC, or RAM. Once the case is open, the inspection reveals a “frankenswitch,” an inventive fix by a previous owner. But it’s the thermal check that tells the real story: the PLA chip is running unusually hot.
Following the Commodore Diagnostic Instruction and Troubleshooting Manual, he checks voltages, reset lines, and clock signals, confirming everything else is within spec. The PLA, however, continues to misbehave. Random color screens—purple, white, blue, and orange—start appearing, sealing the verdict: the PLA is bad.
The faulty PLA repair continues with a clean desoldering job and the installation of a new socketed PLA replacement. After powering up, the C64 finally boots to a blue BASIC screen, confirming success. Chicken 64 then moves on to replacing the homemade switch, cleaning the keyboard, and verifying every port—from joystick to cassette to SID audio output. Each test passes with flying colors, ending with a cheerful game load sequence.
By the video’s close, the Commodore 64 is fully restored, both inside and out. The faulty PLA repair process not only revives a vintage computer but also shows the timeless fun of hands-on electronics repair done the retro way.
