Jump to content

Macintosh Plus Service Source

From RetroTechCollection

The Macintosh Plus volume of Apple's Service Source is Apple's 69-page module-level service manual for the Macintosh Plus. The PDF was created on 21 October 1995 for the Service Source CD. It has Apple's usual chapters (Basics, Specifications, Troubleshooting, Take Apart, Upgrades, Adjustments, Exploded View), each numbered from page 1.

The hosted file was last modified in April 1998. Its symptom charts call the analog board the "power/sweep board".

Contents

[edit | edit source]
Chapter Sections (chapter page) PDF pages
Basics Overview (1) 3
Specifications Introduction (1), Processor (2), Memory (3), Disk Storage (4), I/O Interfaces (5), I/O Devices (6), Sound and Video (7), Electrical (8), Physical (9) 5-13
Troubleshooting General (1); Symptom Charts: Video (2), Drives (3-5), Peripherals (6-7), Miscellaneous (8-11) 15-25
Take Apart Cover (1-2), Power/Sweep Board (3-6), Logic Board (7-12), CRT (13-15), Floppy Drive (16-17), Chassis (18-19) 27-45
Upgrades Memory Upgrade (1-3) 47-49
Adjustments Voltage (1-7), Yoke (8-12), Video (13-17) 51-67
Exploded View one drawing with part numbers 69

What it settles

[edit | edit source]
  • Specifications: 68000 at 7.83 MHz; 1 MB RAM expandable to 4 MB with 150 ns or faster SIMMs; 128K ROM; PRAM in a CMOS custom chip with 256 bytes, backed by a 4.5 V user-replaceable battery; 800K internal drive; 60 W maximum power at 105-125 V AC, 50-60 Hz; 7.5 kg (Specifications pp. 2-9).
  • The voltage adjustment (Adjustments pp. 1-7): voltage test cable 077-0135 on the external drive port, orange lead 11.90-12.75 V, red lead 4.85-5.15 V, one regulator on the power/sweep board, and replacement of the board if both rails cannot be brought into tolerance. Required after replacing the logic board, power/sweep board or CRT. Used on Macintosh Plus General Maintenance.
  • Video adjustments (pp. 13-17): raster 7 in (177.8 mm) wide and 4.7 in (119.4 mm) high; brightness, contrast and focus settings.
  • Memory configurations (Upgrades pp. 2-3): 1, 2.5 and 4 MB, and clipping resistor R8. Used on Macintosh Plus Memory Upgrade Guide.
  • Symptom charts, including the ROM-specific entries: a Plus with ROMs 342-0341-A or -B and 342-0342-A hangs at start-up unless an attached SCSI device is switched on first; a 400K drive with stepper motor serial F518 or higher does not boot with Rev. A ROMs; a programmer's switch that resets the machine must be filed down about 1/16 inch; the logic board ground clip (Rev. D boards and later only) can short to solder points and cause erratic keyboard behaviour. Used on Macintosh Plus Troubleshooting.
  • Exploded-view part numbers: logic board 661-0525; power/sweep board 661-0462 (110 V) and "661-76214" (220 V, as printed); CRT and yoke assembly 076-0103; 800K floppy drive 661-0345; internal drive cable 590-0437; CRT socket cable 590-0160; chassis 805-0766; RFI shroud 805-5047; rear housing 630-5211 (630-5235 platinum); front bezel 810-0379 (810-0385 platinum).

What this manual does not contain

[edit | edit source]
  • No schematics, no component-level parts list and no component values. The power/sweep board and logic board are exchange modules, so the manual cannot source a capacitor list.
  • The Electrical page covers the 105-125 V machine only; the 220 V power/sweep board appears only as a part number in the exploded view.
  • No keyboard or mouse take-apart, and no hard disk information (the Plus has no internal hard disk).
  • No board-level fault finding. For that, see The Dead Mac Scrolls, whose "Early Macs" chapter covers the Plus logic and analog boards by board location.

Pages that cite this document

[edit | edit source]

The Macintosh Plus contains a CRT and a live analog board. Follow CRT Discharge Procedure before working inside one.

Download: Macintosh_Plus.pdf (538 KB)


Retrieved from "https://wiki.retrotechcollection.com/index.php?title=Macintosh_Plus_Service_Source&oldid=20346"