| 摘要 |
PURPOSE:To obtain an oscillator having no spurious at a point close to an output frequency by adding a voltage control type oscillator containing a phase control circuit to attain the substitute oscillation. CONSTITUTION:A voltage control oscillator 11 is provided together with a mixer 13 and a phase control circuit 12. The outputs of the 1st and 2nd voltage control oscillator are sent to the mixer 13, and the differential frequency of both outputs is delivered from the mixer 13. The output of the mixer 13 is divided by a division circuit 14 and compared with the output signal of a reference frequency oscillator 3 by the 2nd phase control circuit 12. Then the oscillation frequency of the oscillator 11 is controlled so that the phase difference of both signals is set at 0. In such a constitution, it is possible to obtain an oscillator having no spurious at a point near an output frequency. |
