Eighty years ago, the November 1936 issue of Popular Science carried the plans for this portable 20 watt AM transmitter for 160-20 meters.

The compact transmitter was designed for operation on a 6-volt storage battery, with a motor-generator supplying the B+ voltage. Also included were plans for an AC power supply.

A type 42 tube was used for the crystal oscillator, with a 6A1 final amplifier. Modulation was handled by two 6A6 tubes.