AJ Lake wrote:
..

I'm sure that our (US) military protects for EMP, but I doubt it is by
using tube equipment. Likely something more modern. Fancy Shielding?
Perhaps you know the technology currently used?

Nope, no idea. When I was in the Air Force working on aircraft comm
radio equipment, "they" told us if a nuke went off, our radios would
most likely not work. I don't think fancy shielding would work since
all radios I know of have a hole in the shield where RF and EMP can
enter. It used to be called the antenna port. Not sure what they call
it in "modern" equipment...

When I was still in the USAF, we had our EC-135 and RC-135 aircraft that
still had some tube type radios on at least HF and UHF bands, ie 618-T
and ARC-34...but...they also had modern radios such as the ARC-190 HF
set. I loved the ARC-190 (Collins). It was a nice radio to use and
work on. Still see them installed on at least National Guard KC-135s
when I get aboard at airshows.