Abstract: A stub tuner includes a first conductor, and a rod-shaped conductor shaft. The first conductor is inserted into a tube axial direction inner side from an opening in a waveguide tube transmitting high frequency waves. The first conductor includes a plate-shaped first shape extending in a direction intersecting a tube axial direction, inside the waveguide tube, and a plate-shaped second shape extending from the outer end in the tube radial direction of the first shape toward the tube axial direction outer side in the tube axial direction. An outer circumferential surface of the second shape is separated from an inner surface of the waveguide tube. An electrical length of the outer circumferential surface in the tube axial direction is ¼ of a wavelength of the high-frequency waves. The conductor shaft is electrically connected to the waveguide tube, supports the first conductor, and extends in the tube axial direction.

Abstract: A waveguide connecting structure includes an inserting waveguide having an inserting conduit line and a flange extending outwardly in a conduit radial-direction, and a receiving waveguide having a receiving conduit line, a receiving structure into which the inserting waveguide is inserted, and stub grooves disposed on both sides of the receiving conduit line outwardly in the direction. The receiving structure has a receiving end face extending in the radial direction and opposing to a flange end face, and an annular receiving inner-circumferential surface disposed outward of the flange and extending in a conduit axial-direction. An electric length of each stub groove in the axial direction from an opening first end to a closing second end is ½ of a conduit wavelength of the stub groove.

Abstract: A waveguide tube connecting member includes a first waveguide tube having a first waveguide path and a flange. The flange has a flange end surface extending from a first opening end of the first waveguide path toward an outer side in a tube radial direction, and a second flange outer peripheral surface which is a part of a first flange outer peripheral surface. The second flange outer peripheral surface is a surface formed in a shape in which a part of the flange has a cavity. An electric length from the first opening end of the flange end surface to the second flange outer peripheral surface along the tube radial direction is (2×N+1)/4 times a wavelength.

Abstract: A waveguide connecting structure includes an inserting waveguide having an inserting conduit line and a flange extending outwardly in a conduit radial-direction, and a receiving waveguide having a receiving conduit line, a receiving structure into which the inserting waveguide is inserted, and stub grooves disposed on both sides of the receiving conduit line outwardly in the direction. The receiving structure has a receiving end face extending in the radial direction and opposing to a flange end face, and an annular receiving inner-circumferential surface disposed outward of the flange and extending in a conduit axial-direction. An electric length of each stub groove in the axial direction from an opening first end to a closing second end is ½ of a conduit wavelength of the stub groove.