| 摘要 |
PURPOSE:To attain oscillations at frequencies over a wide range without any deterioration in characteristics by providing plural oscillation circuits, connecting their output sides to one buffer in parallel, and powering on only a specific oscillation circuit to be put in oscillating operation selectively. CONSTITUTION:Resonance elements 7 and 8 are connected in parallel through capacitors, and a varactor diode 9 is applied with a control voltage CT to vary in equivalent electrostatic capacity. The output side of each oscillation circuit is connected to the input side of a common amplifier (buffer) 10. A power source B is connected between the collectors and emitter of every oscillation circuit during operation. A bias power source, however, is connected to between the base and emitter of an oscillation circuit selectively by a switch 11. For this purpose, the switch 11 is only changed over to obtain two oscillation outputs of different frequencies selectively at the output side of the amplifier 10. |
