The thing is, whereas I wouldn't just turn on a
1980s business
computer with multiple moving parts, the donations chap at TNMOC has
put The Fear into me by sternly warning me Not To Turn Any Of Them On,
because They Will Blow Up.
Well, In my years of doing this hobby I've literally powered up about 30+ old
computers of about the same age as the BBC or older, and in that time I've only ever
had a single blown cap in a single power supply. The worst part of it was the smell. The
bang was a little shocking, but nothing to freak out about. I would just recommend you
stay close to the on/off switch at the mains.
Phil