PURPOSE: To obtain a wide band reception tuner with small and simple constitution which can switch easily bands and with small power consumption and satisfactory distortion characteristics, by using a variable filter which receives different bands at a time and extracts these bands from different outputs.

CONSTITUTION: In a circuit consisting mainly of microstrip lines; lines 20∼24 are set in parallel and successively at the reference position. At this reference position, the lines 20, 22, and 24 are defined as an output terminal 29, an input terminal 30 and an output terminal 31, respectively. While the length of the line 22 is set at 1/4 wavelength of the center frequency of a signal band. The lengths of lines 20 and 21 are smaller than the line 22; while the lengths of lines 23 and 24 are larger than the line 22. It is possible to obtain signals different in band from output terminals 29 and 31 by varying the bias voltage of capacity variable diodes 25 and 26, respectively. In addition, the signals obtained from terminals 29 and 31 have virtually no mutual inteference since the terminal 30, the open terminals of lines 21 and 23 and the terminals 29 and 31 are set at the same position.