Amstrad NC150 Maintenance Guide
The Amstrad NC150 uses the NC100's case and, according to Hans-Jürgen Böhling's surgical guide, the same power arrangement: four AA cells, a lithium backup cell, a 6 V DC adaptor input through fuse F301, and a DC/DC converter with a lithium-backed supply for the RAM and clock.[1][2] The battery, lithium cell, adaptor, memory card and opening procedures on the Amstrad NC100 Maintenance Guide therefore apply. The points below are where the NC150 differs or where its larger memory changes the risk.
What the lithium cell protects
editThe NC150 has 128 KB of RAM against the NC100's 64 KB, and its ROM adds a spreadsheet to the NC100's applications.[3] All of that RAM sits on the lithium-backed supply in Böhling's NC100/NC150 diagram, so removing the AA cells, the adaptor and the lithium cell together loses everything stored in it.[1]
- Back up documents and spreadsheets to an SRAM memory card, or transfer them over the serial port, before changing the lithium cell or opening the case.
- Change the AA cells with the lithium cell in place, and change the lithium cell with good AA cells fitted or the adaptor connected. Amstrad gives this order for the NC100, whose backup arrangement Böhling shows as the same.[4][1]
Batteries and adaptor
edit| Source | Details |
|---|---|
| Main cells | Four AA |
| Backup cell | Lithium coin cell; the NC100 manual specifies a CR2032 |
| Adaptor input | 6 V DC, through fuse F301 |
Sources: Böhling's diagram[1] and the NC100 manual.[4] Tim Surtell's NC users' site also lists 4 × AA cells and a 6 V mains adaptor for the NC150, the same as the NC100, and gives the NC100's adaptor as 300 mA, unregulated.[5] The site's two statements about the plug's polarity contradict each other, so measure the original adaptor and match it; a wrong voltage or polarity can blow the internal fuse.[5] Clean leaked alkaline electrolyte from the battery compartment as described in Battery Explosion, Capacitor or Corrosion Damage.
Opening the case
editBöhling's opening procedure was written for the NC100: five screws on the underside, one of them under the battery cover and one holding the firmware EPROM cover, then lift off the upper case with care because the display flat cable and the speaker lead stay connected to the main board.[1] The NC150 has the same case design.[2] Its board carries more RAM and ROM than the NC100 board Böhling describes, so do not rely on his IC table or link tables for an NC150.
Related pages
editReferences
edit- ↑ 1.0 1.1 1.2 1.3 1.4 Hans-Jürgen Böhling, A Surgical Guide To The Amstrad Notepad Computer. Community document, hosted as File:Amstrad NC100 Surgical Guide.pdf, described at Amstrad NC100 Surgical Guide. The NC150's ROM, RAM and software; the "NC100/NC150" power supply diagram; opening the NC100.
- ↑ 2.0 2.1 Wikipedia, "Amstrad NC100", section "Upgrades". Retrieved 2026-10-02. The NC150 in the NC100's case.
- ↑ Robin Nixon and Chris Nixon, The Amstrad Notepad Advanced User Guide (Sigma Press, 1993), p. 247 (the NC150's ROM, RAM and software) and pp. 187–188 (lock-up recovery on the NC100). Scan at archive.org. Retrieved 2026-10-02.
- ↑ 4.0 4.1 Amstrad plc, Amstrad Notepad Computer user manual (NC100), powering the Notepad and lithium battery, p. 43. Hosted as File:Amstrad Notepad Computer User Manual.pdf, described at Amstrad Notepad Computer User Manual.
- ↑ 5.0 5.1 Tim Surtell, Tim's Amstrad NC Users' Site, "Specifications of the NC Computers" and "Questions & Answers: Hardware". Retrieved 2026-10-02. Power sources of the NC100 and NC150; adaptor rating and conflicting polarity statements; the internal fuse; the NC100 display ribbon cable.