Fifty years ago this month, the May 1974 issue of Elementary Electronics showed how to build this receiver, which dated back another fifty years. It was dubbed an “antennaless” one-tube regen, and was said to work well without an outdoor antenna, instead using only a ground connection to a water pipe.

It uses two spiderweb coils, a type 30 tube (although others are possible), a variable capacitor, and only one resistor and capacitor.

I wasn’t able to find the original design, but according to the 1974 article, it was taken from an issue of Radio News from the “early 1920s.”