Date   : Tue, 18 Nov 2008 22:01:07 +0000
From   : afra@... (Phill Harvey-Smith)
Subject: BBC PSU

Hi,

I have a couple of spare Beeb boards that I don't have cases or PSUs 
for, which I'd like to try running up. I have a 5V psu that I could 
power them off, however the Beeb PSU supplies both +5V and -5V to the 
main board. Looking at the circuit diagram it looks like it's only the 
cassette input amps that use the -5V.

So would it be possible to run a Beeb board off 5V only as long as you 
didn't want to use the cassete ? Alternatly I wonder if you could 
generate the -5V with a little oscilator / rectifier circuit, in the 
same way as the Sinclair Spectrum did ?

Cheers.

Phill.

-- 
Phill Harvey-Smith, Programmer, Hardware hacker, and general eccentric !

"You can twist perceptions, but reality won't budge" -- Rush.