[Milsurplus] VT-xx Tube designations

[Mike Morrow]

>Were the VT-xx designated tubes used before WW II or was that a wartime
>designation?

It goes back at least to the early 1920s.  I have a 1924 Signal Corps training manual covering radio sets then in use, many of which used VT-1 tubes.

A good cross-reference is found at:

http://pages.cthome.net/fwc/VT.HTM

The US Army Signal Corps VT- designations shouldn't be confused with the UK's WWII VT- designations.

Mike / KK5F