Recollections of pre-world war II magnetrons and their applications
G.R. Kilgore · IEEE Transactions on Electron Devices · 1984
The magnetron development work at Westinghouse Research Laboratories in the years 1929 to 1934 and at RCA from 1934 to 1938 is described. The Westinghouse work led to internal-circuit magnetrons with powers on the order of 1W at 9-cm wavelength, and detectable power down to 1.6 cm. A complete microwave relay system using searchlight mirrors was built and demonstrated at the Chicago "Century of Progress" exhibition in 1933-1934. Later work at RCA was directed to longer wavelength in the 60-cm range, where powers of 100 W were obtained. These were CW tubes: the need for pulsed tubes for radar was never disclosed to the tube designers at that time.