Seventy years ago this month, the February 1955 issue of Popular Mechanics showed how to build this transceiver for the two-meter ham band. The heart of the four-tube set was a 6C4 tube which served as superregenerative detector on receive, and as a Colpitts oscillator on transmit. Since the tuning circuit was in common with both circuits, there was no problem with tracking, but care had to be taken to keep the entire transmitted signal within the band.