PURPOSE: To always attain stable reception even when a telemeter radio wave is fluctuated by storing the relation of the VCO on the sweeping side and the fixed side and using the frequency in receiving a telemeter radio wave so as to designate the frequency of the reception section on the fixed side.

CONSTITUTION: An equation representing the relation of frequencies of VCO 4 and VCO 4' to receive a telemeter radio wave in advance is generated and stored in a storage circuit 10. In the case of the operation, the control voltage of the sweeping side reception section 4 is changed stepwise and when the telemeter radio wave is received in the process, the intermediate frequency of BPFs 7, 7' is outputted to a BPF 7 and a pulse is given to the circuit 10 from the detector 9. The digital signal of a D/A converter 8 generating the control voltage of the VCO 4 is held in this timing and the result is inputted to an address of the circuit 10 and a data is read from the circuit 10. Then the read data is given to the D/A converter 8' of the fixed reception section 2 to apply D/A conversion, thereby controlling the VCO 4', then the telemeter radio wave is received by the reception section 2.