| 摘要 |
Channel selecting apparatus wherein it comprises two local oscillators each of which can oscillate with its frequency swept by a sweep voltage, the two local oscillators are so set as to alternately perform sweep initiation and sweep termination, the frequency interval between the sweep initiation and the sweep termination is made equal to a channel frequency interval or 1/n (n being an integer) thereof, the number of times of the sweep initiation or sweep termination is counted, to detect that the operation has been performed by a desired number of times, the sweep of one of the local oscillators is stopped upon the detection, the sweep voltage at the stop is stored, it is applied to a variable reactance element to make the reception possible, a flip-flop is provided which is actuated upon entrance of two signals, and the operation of a circuit for storing the voltage is made by an OR signal between a signal [1 ] produced by the second one of the two signals and a signal [1 ] stopping the sweep after the detection of the desired number of times of the operation of the local oscillators. |
