Doherty amplifier
The Doherty amplifier is a modified class B radio frequency amplifier invented by William H. Doherty of Bell Telephone Laboratories Inc in 1936. In Doherty's day, within the Western Electric product line, the eponymous electronic device was operated as a linear amplifier with a driver which was modulated. In the 50,000 watt implementation, the driver was a complete 5,000 watt transmitter which could, if necessary, be operated independently of the Doherty amplifier and the Doherty amplifier was used to raise the 5,000 watt level to the required 50,000 watt level.