PURPOSE: To prevent the oscillation frequency of a local oscillating circuit from being drawn into a sound carrier wave by setting the oscillation frequency of the local oscillating circuit at a level higher than the oscillation frequency of reception time when a channel is selected.

CONSTITUTION: When contacts 21 and 22 are turned on in case a channel selection switch is changed over to select another channel, the contacts 11 and 12 of a channel selection switch at the left end are turned off. In this case, the potential at the anode side rises instantaneously for LEDs L1, and L2 while the contact 11 is turned off and the contact 21 is turned on. Then this increased voltage is charged to a capacitor 8 via a diode 7 and applied to a control termial 3 for oscillation frequency. A variable capacity diode 10 forming a part of a local oscillating circuit is connected to the next stage of the terminal 3. The diode 10 varies its capacity by the applied voltage, and therefore the oscillation frequency of the local oscillating circuit is set higher than that of a reception mode by the voltage which rises up instantaneously. This action prevents said oscillation frequency from being drawn into a sound carrier wave.