Eighty years ago this month, this schematic for a one-tube regenerative receiver appeared in the August 1945 issue of QST.  It used a 3A5 dual triode, half of which served as detector, with the other half being the AF amplifier.  The use of midget parts allowed the set to be built in a metal case measuring only 4 x 5 x 3 inches.

It appeared in Hints and Kinks, where it had been sent in by Charles Richardson, W8RXY. He reported that two plug-in coils were used to cover 16 through 70 meters. He used it to drive a small speaker, but it could also be used with headphones. He noted that when he was located in England, the set pulled in the States as well as the Orient.