1923 Four-Tube Receiver

Screenshot 2023-02-24 3.06.24 PMThe plans for this handsome instrument were found in the March 1923 issue of Popular Mechanics.  The version shown here contained four tubes, the detector, and three stages of audio amplification to drive the speaker.  Also shown were scaled-down models with one or two stages of audio, for use with headphones.

The set tuned 150-400 meters (750 kHz – 2 MHz) and was said to be a well performing receiver for a reasonable cost.