Oh, the UK valve numbers are a lot more logical that
the US ones (ducks
flames).
OK, you asked for it...
Why did the Post Office and Air Ministry hand out _identical_ type
numbers to _completely_ different tubes? Hmmmm????!?!! If I dig back in
the Boatanchors archives, I can find some examples. I think the VT90 is
one of them.
At least when we pulled that stunt, we gave the tubes prefixes (UV-203A or
WE-203A).
William Donzelli
william(a)ans.net