Date   : Tue, 24 Oct 2006 14:06:17
From   : Jules Richardson <julesrichardsonuk@...>
Subject: Re: One more BBC B to fix

Michael Foot wrote:
> The strange screen display indicates a RAM or addressing problem but having
the
 > power leads removed could indicate a voltage problem.

Hmm, memory's pretty power-hungry stuff. When you checked the PSU, did you put
a 'scope on it to check ripple, or just measure DC voltage? I wonder if it has
  excessive ripple and that's messing things up? If you don't have a 'scope to
check, then an alternative might be to hop on your local freecycle list,
source a 'junk' PC power supply, and try the beeb off that.

It may also be worth taking current readings on the power supply lines; I'm
sure someone with a working beeb could do the same and you could compare notes
to see if anything's obviously out.

The screen display issues are strange. Hmm...

ps. Your email client isn't wrapping lines properly :-(

cheers

Jules