| 摘要 |
PURPOSE:To enable to receive the broadcast having a fragmentary frequency at a part of Europe, by providing the reception detecting circuit to detect the FM detection output and the reference oscillator having the function of voltage controlled oscillator. CONSTITUTION:The broadcast electromagnetic waves are present near the tuning frequency corresponding to the frequency dividing ratio of the variable frequency divider 8 set at the frequency dividing ratio set circuit 14, a given level of electric field strength is given, and when the output of the FM detection circuit 4 is detected with the reception detecting circuit 17 for the tuning within a given range, the change-over switch 20 is switched to the smoothing circuit side. Accordingly, the DC component in the output of the detection circuit 4 changes the oscillating frequency of the crystal oscillator 16 being the reference oscillator. Further, it is operated to be tuned to the broadcast electromagnetic waves operating the reception detecting circuit 17. Thus, reception is made possible even to the broadcast electromagnetic waves having a fragmentary frequency present at a part of Europe. |
