Service Support Tranning Programs Laserwriter Technical Procedures Jan 1985
This file is much more than its title. It is a scan of an Apple Service Support Training Programs binder, 236 pages, and it contains six separate Apple technical documents. The page title names only the first of them, and the word "Training" is misspelt "Tranning" on both the file and the page.
The centrepiece is genuinely important: Apple's own LaserWriter Printer Technical Procedures, marked on its own contents page as "a preliminary version … for internal use only", with comments to be sent to Technical Information Materials Development, Apple Computer, Mailstop 27-V. Individual sections carry revision stamps of rev. Jan 85 and rev. Feb 85. Some items are marked as also appearing on accompanying videotapes.
What is actually in the file
[edit | edit source]1. Apple LaserWriter Printer Technical Procedures
[edit | edit source]- Section 1 — Basics: theory of operation (300 dpi, 6.8 million dots per page; the I/O board
carries 1.5 MB of RAM, 500 KB of ROM and a 68000), locations of major assemblies, printer specifications, setup/operation/preventive maintenance, the two test prints, the toner cartridge, status lights
- Section 2 — Take-Apart: equipment needed, main screw types, safety, ESD (the I/O board is
called out as the most static-sensitive part), covers and panels, I/O board, DC controller PCB, DC power supply / motor drive PCB, laser/scanner assembly, laser beam blocking shutter, registration shutter assembly, preconditioning exposure assembly, fan, ozone filter, high-voltage power supply, power interlock assembly, fuser assembly (699-0306) with heater bulb, thermistor and thermoprotector, transfer guides, feeder guide, transfer corona
- Section 3 — Adjustments: Laser Power Adjustment (P/N 011-7052) — performed after
replacing the DC controller, with a jumper between pins 5 and 6 on J209 and the jumper between J209 pins 7 and 6 removed before adjusting — and Image Skew Adjustment (P/N 011-7051), which involves loosening four mounting screws and two sealed screws on the scanner unit
- Section 4 — Troubleshooting: a quick fix guide, an installation checklist, image-defect
tables (light, dark, black, stains on the back of the paper, sharp horizontal black lines, horizontal fogged stripes, thin vertical lines, faulty registration, waviness) and electromechanical tables (no power, main motor does not rotate, HVPS provides no power, fuser roller heater does not operate, cannot feed manually, paper not fed from cassette, false jam detection, jams not detected, paper-out indicator faults, preconditioning exposure lamps do not light, laser or scanner malfunction, laser or fuser heater malfunction, ready/wait indicator faults), plus paper-jam tables by area, and an appendix of DC Controller Board signals and connectors
2. Macintosh Office (AppleTalk) Technical Procedures
[edit | edit source]A troubleshooting guide built on flowcharts — ONE NODE, TWO OR MORE BUT NOT ALL, ALL NODES, FIRST NODE and RARE CASE — with an appendix explaining the AppleTalk personal network: cable sold in two- and ten-metre lengths, why noisy nodes break the bus, bus termination problems, impedance, dangling cables and circular networks. Apple notes that the AppleTalk bus conforms to the EIA electrical interface specification.
3. DuoDisk Technical Procedures
[edit | edit source]Includes the DuoDisk Analog Card Chip Swapping Chart, which is component-level and is reproduced nowhere else on this wiki. See "What it settles" below.
4. UniDisk Technical Procedures
[edit | edit source]Section 4 — Illustrated Parts List, with Apple part numbers: analog card 661-0287, sub-bezel 970-1258, bottom shield 805-0890, LED cable assembly 590-0140, drive-to-CPU cable 590-0327, Uni/DuoDisk disk mechanism assembly 661-72128, top case 675-5103, top shield 805-0891.
5. ImageWriter (Dot Matrix Printer) and Scribe parts lists
[edit | edit source]From the August 1985 edition of the Technical Procedures Manual, with per-section revision dates. ImageWriter part numbers include platen knob 970-0008, print head assembly 699-0092, front panel PCB with harness 970-0007, carriage drive wire 970-0080, carriage drive motor 699-0093, paper release lever 970-0009, AC line switch (115 V) 970-0011, transformer/switch assembly 699-0095 and DMP CPU card 661-75091. The fuses are 2 A 3AG (740-0101), 5 A (740-0022) and 3 A (740-0021).
6. Lisa / Macintosh XL troubleshooting extracts
[edit | edit source]Rev. 5/17/83 pages from Apple's Lisa Troubleshooting Guide (footed "Page n of 51"): start-up repair procedures and error tones, start-up error icons with the module each implicates, Appendix D start-up error codes, and video repair procedures which open with the warning "If you have never been taught how to adjust…".
What it settles
[edit | edit source]Apple published component-level data for the DuoDisk, and it is here. The DuoDisk Analog Card Chip Swapping Chart lists, by symptom, the chips to change in order, by grid location:
| Symptom | Location and chip, in Apple's order |
|---|---|
| Motor runs but LED is off; will not boot | A1 3469, B4 74LS32, B5 74LS07 |
| Motor and LED on; will not boot | B1 CA3141, B3 74LS125, A1 MC3469, C1 MC3470, B2 74LS33, B5 7407, C3 74LS74, C4 74LS02, C6 ULN2068, C7 ULN2068 |
| Drive reads but does not write | A1 MC3469, B1 CA3141, B2 74LS33, B3 74LS125, C5 74C86, B5 7407 |
| Drive writes when diskettes are write-protected | A1 MC3469 |
Apple qualifies it: symptoms 1 to 4 apply only to analog cards with engineering number 676-[]101; symptom 5 applies to 676-[]101 or 676-[]102. Find the engineering number on the card before using the chart.
And there is a specific, avoidable failure. Apple: "Before replacing any chips carefully inspect the card for melted or broken components, particularly the 74LS125 and C21. If you notice fuzz on the card, return the card to Apple. This usually means that the card was connected to a computer with the power on, and capacitor C21 has exploded." That is a self-inflicted fault with a named component and a named cause — do not hot-plug a DuoDisk.
The DuoDisk illustrated parts list gives screw 400-1604, drive 2 top shield 805-5002, bottom cover subassembly 676-5101, DuoDisk shield 805-5000, drive 1 top shield 805-5001, top cover assembly 676-5103, screw 415-1410, DuoDisk cable 590-0114 and drive-number label 825-0548.
What this file does not contain
[edit | edit source]- The LaserWriter section is preliminary and marked internal-use-only; Apple's later
Service Source LaserWriter volumes supersede parts of it.
- No schematics for any of the six documents. The DuoDisk chart gives chip types and grid
positions, not circuit topology, and no capacitor values beyond naming C21.
- The Lisa extract is partial — the footers show "Page 10 of 51" and similar, so most of the
Lisa Troubleshooting Guide is absent.
- The scan is of a photocopied binder; some pages are skewed and a few figure captions are illegible.
Pages that cite this document
[edit | edit source]- Apple LaserWriter and Apple LaserWriter Plus — the take-apart, the two adjustments and the DC controller appendix
- Apple UniDisk 3.5 — the UniDisk illustrated parts list
- Apple Floppy Disk Drive and Floppy Drive Repair — the DuoDisk chip-swapping chart and the C21 warning
- Apple Lisa Troubleshooting — the start-up error tones, icons and codes
- Apple Desktop Bus and Apple LaserWriter — the AppleTalk bus termination material
- Apple Service Level 1 The Macintosh Office Technical Procedures 072-0163 April 1985 — the fuller Level 1 procedures
The LaserWriter contains a high-voltage power supply and a fuser that runs hot enough to burn. Apple's own safety section is Section 2.A.3.
Download: Service_Support_Tranning_Programs_Laserwriter_Technical_Procedures_Jan_1985.pdf (9.8 MB)