Louis Standley Brown

US Patent:

44233981, Dec 27, 1983

Filed:

Sep 28, 1981

Appl. No.:

6/306077

Inventors:

Ronald E. Jachowski - Paradise Valley AZ
Louis E. Brown - Dallas TX

Assignee:

Decibel Products, Inc. - Dallas TX

International Classification:

H01P 704
H01P 706
H01P 1202
H01P 1207

US Classification:

333229

Abstract:

A microwave tuned cavity has a strip of temperature sensitive bi-metallic material plated with silver attached at one end to the inner surface for the tuned cavity and having its other end extending at an inclined angle to the center of the volume bounded by the inner surface of the tuned cavity. The housing of the tuned cavity expands as its temperature increases, tending to cause the resonant frequency of the cavity to decrease. The strip of bi-metallic material bends slightly as the temperature increases, causing its free end to move toward the surface on which the strip is mounted. This decreases the amount of capacitive loading of the resonant signal in the cavity, tending to increase the resonant frequency caused by thermal expansion of the housing. When the temperature decreases, the free end of the bi-metallic strip moves slightly toward the center of the cavity, thereby compensating for slight thermal contraction of the walls due to the decrease in temperature. In another embodiment of the invention, the bi-metallic strip is attached to the inner surface of a coaxial cavity to compensate for variation in the length of a coaxial resonator as its temperature varies.