| 摘要 |
PURPOSE:To make easy the adjustment of frequency compensation amount and to obtain a low cost oscillator, by providing a means in which the bias for variable reactance coupled wit a solid-state oscillating element is changed with ambient temperature change. CONSTITUTION:A gun diode 7 is located at about 1/2 intube wavelength from a short-circuit plane 11 of a cavity resonator 10, and a varactor diode 1 is added in the resonator with a suitable coupling. A parallel circuit consisting of a thermister 2 and a resistor 3 is connected between a power supply 6 and the diode 1 to give reverse bias to the diode 1, and a resistor 4 connected in parallel with the diode 1 is connected to a power supply 5. The resistance value of the thermister 2 is decreased when ambient temperature rises, the bias voltage to the diode 1 is increased, the junction capacitance of the diode 1 is decreased and the oscillating frequency is made higher. Since the temperature coefficient of a gun diode oscillator 7 is negative, the change in the resonance frequency can be compensated by the change in the capacitance of the diode 1. The amount of frequency versus temperature compensation can be adjusted easily. |
