Express adapters in the UK

From V.I.T.R.I.O.L. <xxxxxx@globalnet.co.uk>
Date
Hi.  I just bought a Turbo Express from bt (it arrived fine, thanks bt), and
I'm trying to get it to work with a mains adapter.  The problem is, when I
use the adapter (a standard multipurpose adapter from an electrics shop),
the screen is too bright - regardless of voltage or the brightness control.
Is there anything I can do about this?  AFAICS it shouldn't be a problem
with UK mains voltage difference or anything, neither should it matter if
it's not an official TE adapter.
Any ideas how I can solve this problem?

Thanks.