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Battery removal - BBC Master

E
arlier in the week I commented on Twitter that I was grateful to someone for mentioning that the Master contains a battery, because I didn't think anything I had in the attic had a battery inside. Well now I feel silly:
 There it is.
 Looks like we may have got away with it! There is leakage but it appears to be contained.
 Shall I call Acorn and ask what part they would approve?
 After a rudimentary clean, it's looking very nice indeed. The cartridge contains Wordwise Plus, as the f-key strip hints:


I think I've been lucky not to have had to deal with alkali spills. But the computer is well-designed, even if any had got out, it would have been contained within the plastic of the case as long as the thing is stored at a reasonable angle.

This job is essential when there are potentially 30-year-old batteries in there. It's important not to just replace the old pack with alkaline batteries, because the Master tries to charge them when switched on. The pack should include a diode and limiting resistor. Mark at Retroclinic supplies two replacement options, both have the necessary components and a sheet explaining how to reset your CMOS memory, and how to reset your Econet Station number if you have one.

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