摘要 |
<p>A frequency ratio between the first frequency band and the second frequency band is increased and stable oscillation is produced. A resonance circuit is connected between the base and collector of an oscillation transistor, the resonance circuit having a midtap (10a), an inductance element (10) with one end thereof grounded, a varactor diode (11) connected in parallel with the inductance element, and a switch transistor (13) switched on or off, wherein either of the collector and the emitter of the switch transistor is connected with the midtap and the other is grounded. <IMAGE></p> |