Troubleshooting and Repairing your Commodore 64
PET 40 Column Clip Test source
PET 80 Column Clip Test source
VIC20 Diagnostic source, thanks to DDHF.
C64 Dead Test Diagnostic Manual, thanks to Sven Petersen.
Commodore 1581 Diagnostic Manual, thanks to Sven Petersen.
Amgia A500/A2000 Diagnostic Kit User’s Manual
Thanks to Jani his C128 Diagnostic Instruction and Troubleshooting Manual is now also added here.