iz8dwf | Commodore PET 8032 repair. ROM/RAM/IO and more faults fixed! @iz8dwf | Uploaded November 2021 | Updated October 2024, 1 hour ago.
Complete repair of a CBM 8032 (Universal PET) motherboard S/N: WG17291

Faults found:
- NE555 on reset circuit
- M53354 TTL decoder IC
- 2 x MOS6520 PIA
- 2 x MOS masked programmed ROMs
- HM4716AP DRAM IC

Timeline:
00:00 - Welcome
00:42 - Mechanical issues
01:16 - Voltage checks
01:43 - CPU reset missing
04:07 - Address decoder fault
09:03 - First bad ROM
10:21 - First bad MOS6520
13:15 - Second bad ROM
17:41 - It lives! (w/ a bad 6520)
20:38 - Fixing IEEE-488
22:26 - Bad RAM IC

PET RAM/ROM daughterboard:
youtube.com/watch?v=bjyGk5zoDMs

8-bit NOP generator introduction:
youtu.be/9Ms6QR4r93I

Mr. Li's 6502 NOP generator socket:
laser.com/product_info.php/item/6502NOP-6502NOP_Chip/products_id/1981

Re-tinning edge connectors:
youtu.be/D3pSjQLOlrc?t=926

Re-tinning faster method:
youtu.be/IHRH3E0EtLg?t=1682

Music on this video:
Guava Juice by Aaron Lieberman