1944 Army-Navy recommended tubes

[W1DAN]

QST!

Perusing an old edition of FM magazine from March 1944, I came across an interesting listing showing recommended receiving and transmitting tubes that the Army and Navy suggest for new military equipment designs.

https://www.worldradiohistory.com/Archive-FM-Magazine/FM-1944-03.pdf

Screen grab attached. Now we know why so many different radios had the same tube types.

Dan

[KA3EKH]

Mind blowing, at least for me that in two short years the new generation of seven and nine pin tubes like the 6AQ5, 6BA6 and 6X4 came out blew away all the big octal that ruled the world before. If you look closely you can see the 6AK5 and 6C4 were there to show what was coming. I remember that I worked on a old Sparta 1 kW AM transmitter that looked like it was designed back in the early forties that used all octal and the like and was surprised to discover it was built in nineteen seventy. Transmitters clung on to the old tubes a lot longer, think Gates ? Harris used 833 tubes well into the sixties and it was not uncommon to find broadcast transmitters in service in the seventies and eighties still using them.

[W1DAN]

Yes...

RCA started introducing miniature tubes in 1939, but with JAN (Joint Army-Navy) requirements of ruggedness, the octal metal tubes ruled the roost for the duration of the war. At the same time, VHF was being exploited and UHF was getting it's start.

And this document revealed the beginnings of the All American 5 revolution in 1945:
https://www.worldradiohistory.com/BOOKSHELF-ARH/Technology/RCA-Books/RCA-New-Miniatures-Tubes-manual-1945.pdf

Dan