Dielectric filter device having conductive strip removed for improved filter characteristics

摘要

The invention provides a dielectric filter device having first bore opening portions arranged between a first electrode formed on an upper surface or side surface of a dielectric block and a second electrode formed on the upper surface to provide a filter for passing a predetermined frequency band, and a second bore opening portion disposed between the second electrode and the side surface of the block. A conductive layer on the outer peripheral side surface close to the second electrode is removed in the form of a strip from at least one portion of the peripheral side surface which portion extends from the upper surface to the lower surface of the block. Unnecessary resonance in a high frequency range outside the pass band can be suppressed without providing an external circuit.