Valve RF amplifier

Shortwave amplifier with tube GU-78B

A valve RF amplifier (UK and Aus.) or tube amplifier (U.S.) is a device for electrically amplifying the power of an electrical radio frequency signal.

Low to medium power valve amplifiers for frequencies below the microwaves were largely replaced by solid state amplifiers during the 1960s and 1970s, initially for receivers and low power stages of transmitters, transmitter output stages switching to transistors somewhat later. Specially constructed valves are still in use for very high power transmitters, although rarely in new designs.[1][citation needed]

  1. ^ Watkins, G.T.; Mimis, K. (2016). "Dynamic Load Modulation RF Amplifier with Current Mirror Based Varactor Driver Amplifier". Active and Passive RF Devices Seminar. Institution of Engineering and Technology. pp. 7 (4 .). doi:10.1049/ic.2016.0007. ISBN 978-1-78561-219-0.