Patent ID: 6600393
Filing Date: 2003-07-29
Classification: H01P

Abstract:
A temperature-compensated rod resonator, comprising:a housing having electrically conducting walls, including side walls, a bottom wall and a top wall, at least one electrically conductive resonator rod extending from said bottom wall towards said top wall, an upper end portion of said rod being located at a predetermined distance from said top wall, to define a resonance frequency, a temperature-compensating plate located adjacent to said top wall and being adapted to change geometrical configuration in response to temperature variations, and coupling means for transferring electro-magnetic energy to and from the resonator, said temperature-compensating plate is a bimetallic plate having a larger diameter than said resonator rod, a central portion of said bimetallic plate being secured to said upper end of said resonator rod, the bimetallic plate, in conjunction with the adjacent top wall defines a capacitance, which has a dominating influence on said resonance frequency, a peripheral portion of said bimetallic plate being permitted to be freely deflected in response to said temperature variations, and capacitance between the bimetallic plate and said top wall is changed to counteract temperature-induced dimensional changes of said housing and said resonator rod.