Abstract: A coaxial cavity resonator filter has a hollow cavity and a post having desired dimensions for achieving desired filter characteristics. A tuning element is supported within a metallic opening and is configured to electromagnetically interact with the post. The tuning element has a conductive core element where the orientation of the tuning element with the cavity is adjusted so as to achieve the desired filter characteristic. An insulator is configured to cover a portion of the conductive core element of the tuning element, at a location where the tuning element and the metallic opening interact. A portion of the insulator is threaded so as to allow the conductive core element vary its orientation within the cavity without contacting the metallic opening.