OSCILLATION CIRCUIT AND METHOD FOR CONFIRMING STABILITY OF OSCILLATION FREQUENCY OF OSCILLATION CIRCUIT

摘要

PURPOSE:To recognize the stability of an oscillation circuit at a short time by making the resonance frequency of a resonance element lower than the resonance frequency of an elastic surface wave element within the range of about several MHz-several tens of MHz. CONSTITUTION:When the resonance frequency f1 of the elastic surface wave SAW resonance element 2 is set higher than the resonance frequency of the resonance element 2 by about 20MHz, a system shifts stably from resonance by the resonance circuit to that of the SAW resonance element. Thus, the resonance frequency of the resonance element is set lower than the resonance frequency of the SAW resonance element by several MHz-several tens of MHz, preferably, about 20MHz. The SAW resonance element 2 is made into an intermittent oscillation state based on the power voltage of a pulse waveform and a spectrum is displayed in a display device such as a spectrum analyzer, for example. The stability of the oscillation frequency in the oscillation circuit can be recognized according to whether f shows about 20MHz.