Seventy-five years ago this month, the May 1944 issue of Radio Craft carried this simple one-tube AC/DC circuit sent in by one Bob Smith of Montclair, NJ.  The set uses a single 12A7 tube as rectifier and detector.  According to Smith, the set would perform on either the standard broadcast band or on shortwave, with appropriate plug-in coils.

The filament voltage is dropped through a standard light bulb, although the schematic shows 70 watts, and the text shows 40 watts.  I suspect 70 watts is the correct value, but we’ll leave it up to the reader to do the calculations.