High-frequency crystal oscillator

摘要

A high-frequency crystal oscillator capable of outputting a signal at a frequency, for example, higher than 500 MHz without using a multiplication amplifier. The high-frequency crystal oscillator comprises a voltage controlled Colpitts oscillation circuit operating at the fundamental frequency of a quartz-crystal element, means for increasing the level of harmonic component in an output from the Colpitts oscillation circuit, an SAW (Surface Acoustic Wave) filter for selecting a component of a predetermined order of the harmonic component, and a broadband amplifier for amplifying the component selected by the SAW filter. The means for increasing the levels of harmonic component is, for example, a resistor for setting the operating point of a transistor in the oscillation circuit such that an output signal is distorted.