The Mitron-An Interdigital Voltage-Tunable Magnetron

This paper describes a voltage-tunable magnetron which can be electronically tuned in the frequency range 1,500 to 3,500 mc. This tube delivers a useful power output of approximately 200 mw and, when used as a local oscillator in a microwave receiver, gives a noise figure 3 db greater than is obtained when a reflex klystron is used with the same receiver. It is shown that temperature-limited operation of the cathode is necessary for coherent operation of the tube and that the operating voltage is greater than that predicted by the Hartree relation. The relation of tube operation and circuit parameters is discussed.