摘要 |
<p>The present invention has: a conductive casing body having cavity resonators; a conductive cover which covers the cavity resonators; resonator elements which are positioned within the cavity resonators one end whereof being connected to the casing body and another end whereof being a free end; and movable conductors which are positioned in spaces between the free ends of the resonator elements and the conductive cover. A tunable band -pass filter is thus implemented whereby it is possible to easily change a resonance frequency of a cavity resonator and a coupling quantity between the cavity resonators, and which is inexpensive and has a simple structure.</p> |