Needless to say, this circuit we found in a 1943 documentation is quite critical. Using 4 valves it is powered by the mains. We remember that the UHF range in those days was different from what we consider today. It was between 30 and 300 MHz.

Needless to say, this circuit we found in a 1943 documentation is quite critical. Using 4 valves it is powered by the mains. We remember that the UHF range in those days was different from what we consider today. It was between 30 and 300 MHz.