Early magnetrons (negative resistance magnetrons and cyclotrons) were inefficient and had no practical significance. 1935 A.L.Samuel first developed a multi-cavity magnetron model. In the same year the French Camille Gutton with a magnetron to produce 16 cm wavelength, November 29 German H.E. Hollmann registered a more patented multi-cavity magnetron patent. While the Soviet Union claimed that the first multi-cavity magnetron is the Soviet Union project
Division Н.Ф. Alexei Yavi and Д.Е. Ma Liao Luofu made in 1936 ~ 1937 years. In 1939, the British physicist H.A.H. Bout and J.T. Randall made a fully practical multi-cavity magnetron. In the Second World War, multi-cavity magnetrons were widely used in military radar transmitters, played a significant role. By 1945, its operating frequency has reached 30 GHz. Generally known as the magnetron, that is, multi-cavity magnetron.