Amstrad PC 2086 Service Manual
The PC2086 S/D/30 Personal Computer / PC12 MD / PC12 HRCD / PC14 CD / PC14 HRCD Monitors Service Manual is Amstrad plc's service manual for the PC2086 and its monitors. The contents list runs to page 60; the scan has 58 PDF pages with a machine-read text layer, and in the PC14 sections its pages are not in contents order.
Contents
[edit | edit source]Amstrad's contents list, with printed page numbers:
- Technical specification – 2; safety tests – 2
- PC2086 S/D/30 section: alignment instructions 3, electrical parts list 4, mechanical exploded view 5, keyboard exploded view 6, main/LED PCB top view 7 and bottom view 8, power switch PCB 9; chassis schematic diagrams for memory and disc controller 10, CPU and memory 11, expansion bus 12, printer port control 13, support controller 14, video 15, keyboard controller 16, keyboard 17 and power supply 18
- PC12 MD/O monitor – 19: alignment instructions 19, electrical parts list 20, chassis schematic 21–22, cabinet exploded view and parts list 23, monitor/CRT/LED PCB 24
- PC12 HRCD/O monitor – 25: alignment instructions 25, electrical parts list 26, monitor and CRT/LED PCBs 27, chassis schematic 28–30, cabinet exploded view and parts list 31
- PC14 CD/O monitor – 33: alignment instructions 33, electrical parts list 34, monitor PCB 35, chassis schematic 36–38, cabinet exploded view and parts list 39
- PC14 HRCD/O monitor – 41: alignment instructions 41, electrical parts list 42, monitor and CRT/LED PCBs 43, chassis schematic 44–46, cabinet exploded view and parts list 47
- PC12 MD/D monitor – 49: electrical parts list 50, monitor and supply PCBs 51, wiring diagram 52, monitor PCB 53, cabinet exploded view and parts list 54
- PC12 HRCD/D monitor – 55: electrical parts list 56, wiring diagram 57, CRT/monitor/power supply PCBs 58, schematic 59, cabinet exploded view and parts list 60
What it covers
[edit | edit source]The specification on page 2 gives an 8086 at 8 MHz with 16-bit memory, an 8087 socket, 640K of parity-checked RAM, three 8-bit expansion slots, 720K floppy drives and a 30 MB hard disc option, with MS-DOS 3.3, Windows 2.03 and GW-BASIC. The system unit measures 365 × 140 × 395 mm. The monitor table lists the PC12MD (12-inch mono), the PC14CD (14-inch colour, 0.42 mm dot pitch), the PC12HRCD (12-inch, 0.28 mm) and the PC14HRCD (14-inch, 0.29 mm).
The PC2086 alignment instructions (p. 3) set the power supply with a digital voltmeter at four test points on the power PCB:
| Rail | Test point | Control | Setting |
|---|---|---|---|
| +5 V | A | VR604 | 5.15 V ±0.1 V |
| +12 V | B | VR603 | 12.15 V ±0.2 V |
| −5 V | C | VR601 | −5 V ±0.1 V |
| −12 V | D | VR602 | −12.00 V ±0.2 V |
A fifth step sets the +12 V protection with VR606, with pins 1 and 3 of Q605 shorted and an oscilloscope on the link, and a sixth sets the real-time clock with trimmer TC101 against a timing meter on pin 21 of IC134. The monitor safety tests (p. 2) are a 1.5 kV RMS flash test for 3 s, an insulation test requiring more than 4 MΩ, and a mains-lead earth continuity of no more than 0.5 Ω.
Amstrad's notes to engineers (p. 3) set the repair policy: no component-level repair of the main CPU PCB, which is replaced once a fault is confirmed; the same for the floppy and hard disc drives; and component-level repair of the monitors.
What this manual does not contain
[edit | edit source]- Component-level data for repairing the main CPU board or the drives, by Amstrad's policy above.
- Alignment instructions for the PC12 MD/D and PC12 HRCD/D. Each section carries the note "Alignment instructions will be published as an amendment".
- Fault-finding flow charts.
- The PC2286, PC2386 or other models. See Amstrad PC 2386 Service Manual.
Pages that cite this document
[edit | edit source]- Amstrad PC2086 · Amstrad PC2086 Maintenance Guide · Amstrad PC2086 Troubleshooting Guide · Amstrad PC2086 Capacitor Replacement Guide
- Amstrad PC2286 and its guides: the PC12 and PC14 monitors sold with the PC2286
- Amstrad PC1640 Capacitor Replacement Guide: C124
Download: Amstrad PC 2086 Service Manual.pdf