SE332234

1,022,707. Magnetrons. RAYTHEON CO. Aug. 25, 1964 [Sept. 25, 1963], No. 34752/64. Heading H1D. A frequency stabilized magnetron includes a plurality of anode resonant cavities disposed around a cathode to form an interaction space, a stabilizing cavity longitudinally adjacent the interaction space, means for symmetrically coupling energy between the stabilizing cavity and the anode resonant cavities, and a magnet which includes a member of magnetic material disposed between the interaction space and the stabilizing cavity. Anode vanes 11 extend from ring 12 towards cathode 10 to form a plurality of resonant cavities, alternate vanes being connected by straps 15 and 16. The stabilizing cavity 21 is coupled to the vane structure by a probe 22 which extends through a hollow core 26 of the polepiece 14 of the magnet 18, a plurality of legs 23 connecting the probe to alternate vanes. The flexible upper wall of cavity 21, which is preferably operated in the TM 01 mode, is adjustable by screw 36 to permit frequency tuning of the magnetron, the output from which is taken from a coupling loop 30. In a modification (Fig. 3, not shown), a plurality of coupling loops 42 couple alternate vanes to the stabilizing cavity 51, and the magnetron output is derived from a coaxial cable connected to the anode straps 45, 46. In a further embodiment (Fig. 4, not shown), the coupling loops 42 are replaced by irises. The anode resonant cavities may be of slat or pole rather than vane-type.