Eighty years ago this month, the May 1940 issue of Popular Mechanics showed how to put together this project for advanced radio hobbyists. It was a three-band six-tube superheterodyne receiver capable of tuning 530 kHz to 18 MHz. It was an update to a four-tube set shown in the December 1939 issue, as that project had left space on the chassis for the upgrade, and most of the parts from the original set were re-used.

Unfortunately, I don’t see any indication that the set had a BFO, so while it was probably a good receiver for voice signals, it couldn’t be used for code.