The December 1940 issue of Radio and Television Magazine showed how to put together this three-tube set for the broadcast band. A 6J7 served as regenerative detector, with a 6J5 audio amplifier. The 6C5 was pressed into service as rectifier, with a line-cord resistor dropping the filament voltage.

You’ll get some idea of the size by the fact that the front panel is made out of a standard household outlet cover. With a short antenna strung around a picture frame or on the floor behind furniture, the set would pull in local stations. Strong local stations might be strong enough to run a speaker.