PURPOSE: To attain ease of manufacture and adjustment or the like of a circuit by providing a VCO having an oscillation frequency in response to the received 2nd local oscillator signal to utilize the oscillating signal of the VCO to the 1st local oscillator signal of a transmission system and to lock the oscillating signal with the oscillating signal of the VCO in phase.

CONSTITUTION: Signals and frequencies of a pilot signal of a received IF output and a reference pilot signal from a pilot signal generator 5 are compared by a phase detector 6 to control the VCO8 and the result is supplied to a phase detector 11. A loop comprising a loop filter 14, VCO13 and a mixer 12 is connected to the detector 11 and the output signal of a local oscillator 15 of the transmission system and an oscillation signal from he VCO13 are mixed at the mixer 12. A signal as the result of conversion of the signal of the VCO13 into a signal of 100MHz band is fed from the mixer 12 to the detector 11 to compare in phase with the output of the VCO8 of the reception system, and the VCO13 is controlled so as to make the phase difference zero. Then the output of the VCO13 is fed to a mixer 3 as the 2nd local oscillator signal of the reception system to take synchronism with the transmission system.