BBC Microcomputer Service Manual October 1985 Section 3
Section 3 of Acorn Computers' BBC Microcomputer Service Manual, part number 0433,001, Issue 1, October 1985 — the Additional Upgrades volume, in 20 pages.
It contains two dealer upgrade procedures:
- BBC Microcomputer Model B — 1770 Disc Interface. Fitting instructions for the 1770 disc interface daughter board, explicitly applicable to any issue of the Model B main PCB and explicitly not suitable for the Model B+. Covers the main-PCB modifications, the pin numbering needed to install the module, fitting the module itself, and fitting the 1770 Disc Filing System ROM — including a table of what to do with machines that already carry 0.90 DFS, Econet, or both.
- 64K Sideways RAM daughter board. Fitting instructions for the Model B+, including the two main-PCB track cuts required (IC40 pin 13 to pin 14, and the track to IC52 pin 10).
The scan carries a text layer and is searchable.
Download here: BBC Microcomputer Service Manual October 1985 Section 3 Additional Upgrades.pdf
Other sections of this manual
edit- BBC Microcomputer Service Manual October 1985 — Section 1, Models A and B
- BBC Microcomputer Service Manual October 1985 Section 2 — Model B+