| 摘要 |
PURPOSE:To obtain stable oscillation by constituting the titled oscillator with 3-stage of common emitter amplifiers, a dielectric resonator, a capacitor having a small capacitance coupling a base input and a collector output of the amplifiers and the resonator and a vari-cap diode to vary the frequency so as to apply temperature compensation without using AFC. CONSTITUTION:Since the resonator 1 is coupled by the capacitors 2, 3 having a small capacitance, the Q of load is increased and the oscillation having high purity is obtained. The circuit is oscillated at a frequency in a manner that the sum of phases between the side of an amplifier 26 at boundaries of points D, E and the side of the resonator 1 are zero. Further, a temperature causing a voltage change is set by resistors 31, 32 and resistors 33, 34 can adjust the voltage change with respect to temperature. In applying the correcting voltage to a point A and applying a voltage adjusting the oscillating frequency to a point C, the voltage applied across the vari-cap diode 5 is reduced as temperature rises and the capacitance is increased, causing the oscillating frequency to be lowered. Thus, the frequency fluctuation with respect to the temperature of the resonator itself is compensated. |
