Pulling this thread a little to one side:

The "Radiotron Designer's Handbook" from the Amalgamated Wireless Valve
Company (Australia) had a number of tricks to reduce the tube count in
radios. Its main interests are AM and shortwave broadcast radios.

The book was sold by RCA in the USA. Anyone interested in tube radios
should have a copy. It's a couple of inches thick. It was last issued in the
1950s - mine includes info on FM broadcast receivers.