A Classic First Step: The Collins KWM-1 SSB-CW Transceiver

摘要

The Collins KWM-1 was a major step toward Amateur Radio equipment as we know it today. It was the first single-sideband (SSB) transceiver ever. It came out in 1957, as a result of a project built with Collins contributing parts and material to Gene Send, a Collins engineer. Arthur Collins, founder of Collins Radio Co., would often donate parts to his engineers to try out ideas on their own time. Gene made a separate transmitter that used the SSB mechanical filter in his 75A-4 receiver. It also used the main tuning permeability tuned oscillator (called the PTO by Collins) and the crystals to convert the amateur bands to the tunable IF used in the 75A-4. This device, with the 75A-4, created an SSB-CW transceiver. Art Collins liked the idea and, with an eye on mobile applications, the KWM-1 was designed and marketed by Collins.