• Issue 1, 1984: Datasette 1 - Model 1530, 1531
  Datasette engineering change due a noise interferences
• Issue 5, 1984: Computer 2 - Model C16
  Troubleshooting aides (PDF)
• Issue 6, 1984: Computer 3 - Model PLUS 4
  Troubleshooting aides
• Issue 7, 1984: Computer 4 - Model C16, PLUS 4
  Line definitions (PDF)
• Issue 4, 1985: Disk Drive 1 - SDF 1001
  Device number change
• Issue 6, 1985: Computer 1 - Model C-64, C-16, Plus 4
  Engineering change that adds four protection diodes to the serial port.
• Issue 9, 1985: Computer 3 - Model C-128
  Commodore 128 Service Manual update
  • Commodore 128 Service Manual updated page 65
  • Commodore 128 Service Manual updated page 66
• Issue 11, 1985: Disk Drive 3 - Model 1541 "B"
  Addendum for the Commodore 1541 Service Manual.
  • PCB Assembly #250448 - Board layout
  • PCB Assembly #250448 - Parts list
  • 1541B Schematics
• Issue 15, 1985: Disk Drive 4 - Model 1541
  Common failure: drive runs continously - troubleshooting guide
• C128 ROM upgrade announcement

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