Alps Electric Co., Ltd.

Shigeru Sato

Hirokazu Watanabe

Shigetaka Suzuki

A signal selecting circuit comprises a first switch means connected between a first input terminal and a common output terminal, a second switch means connected between a second input terminal and the common output terminal, a first microstrip line for connecting the first switch means and the common output terminal, and a second microstrip line for connecting the second switch means and the common output terminal, wherein a length of the first microstrip line is set to be approximately odd-numbered times of 1/4 wavelength of a frequency of an image signal relative to the second mode reception signal, and a length of the second microstrip line is set to be approximately odd-numbered times of 1/4 wavelength of a frequency of an image signal relative to the first mode reception signal.

Signal selecting circuit

According to the present invention, there is provided a satellite broadcast receiving converter which comprises a waveguide in which the broadcast wave travelling therein travels as a first TE11 mode linearly polarized wave and as a second TE mode linearly polarized wave intersecting at a right angle with each other, a first probe disposed at a predetermined position within this waveguide for detecting the first linearly polarized wave, a first reflecting conductor disposed approximately 1/4 of the wavelength separate from the first probe in the direction in which the electric wave travels for reflecting the first linearly polarized wave, a second probe disposed in the neighborhood of the first reflecting conductor for detecting the second linearly polarized wave, and a second reflecting conductor disposed approximately 1/4 of the wavelength from the second probe in the direction in which the electric wave travels for reflecting the second linearly polarized wave. On the second reflecting conductor, an electrically conductive columnar portion is provided for protrusion so that it may lie in the neighborhood of the inner peripheral surface of the waveguide on the axial line thereof.

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Miyagi-ken, Japan

Shigeru Sato