Abstract: An electronic tuning AM/FM radio receiver utilizes a common circuit for both FM reception and AM reception to stop automatically the scanning operation on the local oscillation frequency at its optimum point thus attaining simplicity of circuit structure, whereas the prior art needed a pair of complicated circuits for FM reception and AM reception. There is a local oscillator for AM reception and a second local oscillator for FM reception provided independently or commonly to each other, a control circuit provided for controlling selectively the scanning operation of the local oscillators and holding the local oscillation frequency of the selected one of the local oscillators at a scanning frequency when a tuning signal is applied, and a converter provided for converting an FM intermediate frequency into an AM intermediate frequency.

Abstract: A digital oscillator is provided which has digital oscillation outputs corresponding to the sweep speed of the local oscillation frequency of a local oscillator included in an electronic tuning radio receiver. An oscillation frequency controlling element which forms an external oscillation frequency control section of the digital oscillator and a circuit constant variable upon variations in its working length, is mounted on an operator operable knob shaft on the operational panel of the radio receiver around the rotation path of a sweep speed controlling element mounted coaxially thereto. The sweep speed controlling element and the oscillation frequency controlling element are connected to an input section of the digital oscillator. There is further provided a Distance/LOCAL receiver mode selecting element coaxially on the knob shaft.