Commodore 64 - Faulty RAM spot technique, test, piggybacking, repair & play...

Today, let's repair a Commodore 64 with RAM chips error NAME C64 MANUFACTURER Commodore TYPE Home Computer ORIGIN U.S.A. YEAR 1982 END OF PRODUCTION 1993 BUILT IN LANGUAGE Basic KEYBOARD Full-stroke 66 keys with 4 function keys CPU 6510 SPEED 0.985 MHz (PAL) / 1.023 MHz (NTSC) CO-PROCESSOR VIC II (Video), SID (Sound) RAM 64 KB ROM 20 KB TEXT MODES 40 columns x 25 lines GRAPHIC MODES several, most used : 320 x 200 COLORS 16 + 16 border colours SOUND 3 voices / 9 octaves, 4 waveforms (sound output through TV) SIZE / WEIGHT 40.4 (W) x 21.6 (D) x 7.5 (H) cm / 1820 g I/O PORTS video output (composite, chroma/luma and sound in/out), 2 x Joystick plugs, Cartridge slot, Tape interface, Serial, User Port, TV RF output BUILT IN MEDIA Cassette unit. Provision for 170 KB 5.25'' floppy disc unit (1541) POWER SUPPLY External power supply unit Thanks for supporting this channel:   / cyberhug