A frequency switching signal for switching a reception frequency of an antenna based on a reception success or failure signal output from a detection circuit and a standard time code output from a demodulator is output to a reception frequency selection circuit. The reception frequency is switched to the frequency which is the same as an intermediate frequency other than that of the standard radio waves, and at the same time, an output temporarily stopping signal is output to a local oscillation circuit to temporarily stop the output of a local oscillation signal of the local oscillation circuit, enabling to output the reception signal which was received by the antenna as the intermediate frequency signal without synthesizing and converting it in the frequency conversion circuit to be detected by a detection circuit.Thereby, the reception of the radio wave composed of a plurality of frequencies can be realized with a simple structure.