PURPOSE: To stably and surely control a BPF by forming an oscillation circuit so as to integrate the BPF automatically when a frequency of a reference signal and a frequency of the BPF are deviated.

CONSTITUTION: When an input signal is a chrominance signal, a switch 14 is thrown to the position of a contact 14b so as to give an output of an adder 18 to a BPF 12 for a period between the chrominance signal and a burst signal. A sum signal between an output of the BPF 12 of a prescribed level via a limiter 24 and a reference signal is outputted from the adder 18. The center frequency of the BPF 12 is controlled to be brought into a frequency fO of the reference signal by using the oscillation frequency. When a level of an output Vout of the reference signal component in response to an input Vin of the reference signal is smaller than the oscillation level, the BPF is oscillated at the frequency f0 of the reference signal.