Abstract

ABSTRACT OF THE DISCLOSURE A dielectric filter (Fig. 16) for frequencies higher than VHF band comprising a closed conductive housing (112), an input and an output provided at both the extreme ends of said housing (112), a dielectric body (111) with a plurality of linear parallel grooves (118) arranged in said housing (112), a plurality of conductive rods (113) with the length of approximately 1/4 wavelength mounted in said dielectric body (111) between said grooves (118) so that one end of said resonators (113) is fixed to the common plane of the housing (112), a capacitor (114,115) provided between the other end of resonators (111,113,118) and said conductive housing (112) so that an electrode (115) of said capacitor may be trimmed by a laser beam to adjust the resonating frequency of each of said resonators (111,113,118) and a plurality of conductive rods (137) provided in said grooves (118) for improving the spurious characteristics of the filter. The dielectric filter, compared with those of the prior art, is simple in structure, easy to adjust the characteristics of the filter, and/or the resonating frequency of the resonators, and has small spurious characteristics.

IPC Classes  ?

• H01P 1/205 - Comb or interdigital filters; Cascaded coaxial cavities