LaserWriter II Service Source
The LaserWriter II volume of Apple's Service Source is a 225-page service manual covering the LaserWriter II SC, II NT, II NTX (and NTX-J), IIf and IIg. The PDF's creation date is 29 October 1995.[1] It names some components by designator (capacitor C211, switches SW301 and SW302) and gives measurable test values and Apple's own maintenance schedule.
Specifications
[edit | edit source]| Item | Value |
|---|---|
| Engine | Canon SX; electrophotography with single-component dry toner; semiconductor laser with a rotating six-faced prism scanning mirror; 300 dpi |
| Speed | 8 pages per minute (7 on legal paper); no monthly duty-cycle limit; minimum life 300,000 pages; major service interval 100,000 copies |
| Line voltage | US/Japan 100-115 V, 50-60 Hz; Europe/Australia 220-240 V, 50 Hz |
| Power | Standby 170 W average; operating 900 W maximum (115 V), 780 W (220 V), 880 W (240 V) |
| Size and weight | 51 × 48 × 21.6 cm (20 × 18.9 × 8.5 in); 21 kg (46 lb) |
| Operating environment | 10-33 °C; 20-80% relative humidity |
| Model | CPU | DRAM | ROM | I/O | Languages |
|---|---|---|---|---|---|
| II SC | 68000, 7.45 MHz | 1 MB | 16 KB | SCSI, ADB | QuickDraw |
| II NT | 68000, 11.16 MHz | 2 MB | 1 MB | RS-232/422, LocalTalk, ADB | PostScript, Diablo 630 subset |
| II NTX / NTX-J | 68020, 16.67 MHz | 2 MB (NTX-J 4 MB), expandable to 12 MB | 1 MB, expandable to 8 MB | RS-232/422, LocalTalk, SCSI, ADB | PostScript, Diablo 630 and LaserJet Plus subsets (no emulation on NTX-J) |
| IIf | 68030, 20 MHz | 2 or 5 MB, expandable to 32 MB | 2 MB | RS-232/422, LocalTalk, SCSI | PostScript Level 1 and 2, HP PCL4 |
| IIg | 68030, 25 MHz | 5 or 8 MB, expandable to 32 MB | 2 MB | RS-232/422, LocalTalk, SCSI, Ethernet | PostScript Level 1 and 2, HP PCL4 |
The Intro Dates page gives July 1990 for the SC, NT and NTX and October 1991 for the IIf and IIg.[2] The first date is not an introduction date: Apple introduced the LaserWriter II SC, NT and NTX in January 1988.[3]
Contents
[edit | edit source]- Basics (PDF pp. 3-13): product information, startup test page, service test page, preventive maintenance, parts replacement schedule
- Specifications (PDF pp. 15-27): general, intro dates, logic board, performance, paper, built-in fonts, environmental, electrical, physical
- Troubleshooting (PDF pp. 29-54): IIf/IIg diagnostic, capacitor discharge, controller board readings, roller diameters, drum check, top-cover interlock, circuit board diagrams, connector locators, flowcharts, wiring diagram (110 V)
- Take Apart (PDF pp. 56-201): I/O board, base unit, controller boards, cover set, laser/scanner assembly, fuser assembly, feeder, ozone filter, fans, power supply block, DC power supply, distribution board, high-voltage power supply, main motor, transfer guide and corona, paper feed and more
- Upgrades (PDF pp. 203-205): NTX ROM upgrade, IIf/IIg ROM upgrade kit
- Additional Procedures (PDF pp. 207-223): I/O board installation, voltage conversions, laser power output check
- Exploded View (PDF pp. 224-225)
What it settles
[edit | edit source]Capacitor C211: when the fusing system fails, the DC controller board cuts current to the fuser heater and charges C211 to prevent overheating, and the printer will not restart until C211 is discharged. Either leave the power off for about 30 minutes, or unplug the printer, remove the bottom panel and lower cover, and jumper the two wires at the base of C211 on the DC controller board with a conductive tool. Apple shows a length of lead solder, which is ductile and less likely to damage the board than a screwdriver.[4]
Repetitive defects: match the spacing of repeated marks to a roller circumference. Transfer guide: roller to corona assembly 0.5 in (13 mm), upper metallic roller 1.5 in (38 mm), lower black roller 1.75 in (44 mm). Fuser: lower roller 2.56 in (65 mm), upper roller 3.16 in (80 mm). Toner cartridge: developer roller 2.0 in (51 mm), photosensitive drum 3.75 in (95 mm).[5]
Laser power output: with the laser power checker (076-0121, discontinued) in the laser access hatch, drum sensitivity switches SW301 and SW302 held and the service test page button pressed, a multimeter on the 200 mV range should read 17.6 ± 1.6 mV. No adjustment of the laser power circuitry is possible on the LaserWriter II. Do not open the laser access hatch or disconnect the optical fibre cable with the printer switched on.[6]
Preventive maintenance: Apple's schedule is to clean, every 12 months or at each service call, the primary corona wire (brush supplied with the printer), transfer corona wire (cotton swab and isopropyl alcohol), transfer guide (cloth dampened with water), fuser rollers (fuser cleaning pad), separation claws, paper guide and lower delivery guide (cloth dampened with alcohol), and the feeder guide, registration rollers and exterior case (cloth dampened with water). Never use an ammonia-based cleaner, which discolours the plastic, and leave the printer off for at least 5 minutes before touching the fuser rollers.[7] Every 50,000 prints replace the ozone filter and check both fans. Every 100,000 prints replace the fuser assembly, transfer guide assembly, preconditioning exposure assembly, paper feed roller assembly and transfer corona assembly; the LaserWriter II refurbishment kit, P/N 652-0597, contains one of each.[8]
Voltage conversion: printers built for the USA and Japan run at 110-115 V and those for Europe and Australia at 220-240 V. Converting one to the other means replacing the power supply block, the DC power supply and the fuser assembly with the parts for the new voltage.[9]
What this manual does not contain
[edit | edit source]There is no circuit schematic and no parts list of individual components. The circuit board diagrams are connector and switch locators, and the wiring diagram shows connections and supply names between boards, not board circuitry. C211 is named for the discharge procedure; its value is not printed.[10]
Pages that cite this document
[edit | edit source]- Apple LaserWriter II NT
- Apple LaserWriter Printers Volume I
- Laserwriter Ii Nt Ntx Owners Guide 1988 and Laserwriter Iint Ntx Owners Guide 1990
- Apple Laserwriter Ii Service Training Participant Manual Version 1.1 Oct 1992 and Service Training Laserwriter Ii Service Course Participant Manual Version 1.1 1996
- Service Training Introduction To Laser Printer Service Version 1.0.1 1996 and Service Training Introduction To Laser Printer Service Version 1.0 1992
- Introduction To Laserwriter Service 2.0 1997
- Envelope Feeder Service Source, Inside The Apple Laserwriter 1989, Programming the LaserWriter 1991, The Laser Writer Family 1992
Download: Laserwriter ii.pdf
References
[edit | edit source]- ↑ Apple Computer, Inc., LaserWriter II (Service Source), 225 pp. Hosted as File:Laserwriter ii.pdf.
- ↑ 2.0 2.1 2.2 LaserWriter II Service Source, Specifications, pp. 2-14 (PDF pp. 15-27).
- ↑ Dan Knight, "1988: LaserWriter II, A/UX, CD-ROM, and Mac IIx", Low End Mac. Retrieved 2026-09-30.
- ↑ LaserWriter II Service Source, Troubleshooting, Capacitor Discharge, pp. 2-4 (PDF pp. 30-32).
- ↑ LaserWriter II Service Source, Troubleshooting, Roller Diameters, pp. 6-7 (PDF pp. 34-35).
- ↑ LaserWriter II Service Source, Additional Procedures, Laser Power Output Check, pp. 12-17 (PDF pp. 218-223).
- ↑ LaserWriter II Service Source, Basics, Preventive Maintenance, pp. 8-10 (PDF pp. 10-12).
- ↑ LaserWriter II Service Source, Basics, Parts Replacement Schedule, p. 11 (PDF p. 13).
- ↑ LaserWriter II Service Source, Additional Procedures, Voltage Conversions, pp. 10-11 (PDF pp. 216-217).
- ↑ LaserWriter II Service Source, Troubleshooting, Circuit Board Diagrams, Connector Locators and Wiring Diagram, pp. 11-25 (PDF pp. 39-54).