| 摘要 |
PURPOSE:To provide an oscillator circuit which assures the highly stable frequency inexpensively. CONSTITUTION:In an Colpitts oscillator circuit consisting of a coil 86, the capacitors 87 and 88, and a variable capacitor 89 connected to a transistor TR 82 serving as an amplifier element, a surface acoustic wave oscillator 93 is connected between both capacitors 87 and 88 and the emitter of the TR 82 to constitutes an oscillator circuit 62A. Each constant of the circuit 62A is set so as to set the oscillation frequency at a prescribed level and also to satisfy the oscillation conditions (position feedback/loop gain are equal to 1). In such a constitution, the frequency of the output signal is stabilized to the variance of the ambient temperature in comparison with an LC oscillator circuit. Furthermore the power consumption is reduced and the stability is improved to the variance of the ambient temperature or the power voltage in comparison with a case where the crystal resonators of the B-C and B-E piercing circuits are merely replaced with the SAW resonators owing to application of the CE feedback. |
