Abstract: A magnetron includes an anode with an anode casing at least partly surrounding the anode. A pair of permanent magnets on each side of the anode define an interaction region and create a magnetic circuit defining a magnetic field through the interaction region. A mass of magnetically permeable material is positioned in a vicinity of the magnetic circuit. The mass is arranged to be slidable over the anode casing. A locking device secures the position of the mass to set the strength of the magnetic field through the interaction region.

Abstract: A magnetron includes an anode with an anode casing at least partly surrounding the anode. A pair of permanent magnets on each side of the anode define an interaction region and create a magnetic circuit defining a magnetic field through the interaction region. A mass of magnetically permeable material is positioned in a vicinity of the magnetic circuit. The mass is arranged to be slidable over the anode casing. A locking device secures the position of the mass to set the strength of the magnetic field through the interaction region.

Abstract: A magnetron of the type having a strap ring has protruding regions of the strap ring arranged so as to increase the capacitance between the strap ring and another strap ring or between the strap ring and anode vanes. Increasing the capacitance at selected portions of the strap ring allows control of the frequency response of the magnetron.

Abstract: A magnetron output arrangement includes a coaxial output adapted to be coupled in an endfire configuration to a rectangular waveguide. The waveguide has a flange for mating with the magnetron output arrangement. The coaxial output includes a central conductor. The output arrangement further includes a plate located in a predetermined position with respect to the central conductor. The plane of the plate is arranged to be substantially perpendicular to the axis of the coaxial output. The plate is located a predetermined distance from the end of the central conductor, such that the coaxial output in use couples with the plate so that the output coupling is substantially the same regardless of the type of waveguide flange employed.