Technique for measuring the acceleration sensitivity of SC-cut quartz resonators

A simple method for measuring the acceleration sensitivity of doubly-rotated quartz resonators is discussed. This method utilizes readily available electronic components and the voltage-frequency effect in doubly-rotated cuts to determine both the phase and magnitude information. The method is based on monitoring vibration-induced FM sidebands of an oscillator with a spectrum analyzer and using acceleration compensation for SC-cuts by means of the voltage-frequency effect. An op amp with reversible polarity is used to apply a voltage, which is proportional to an accelerometer output, to the crystal. Examples of the application of the method are given. Typical reductions or enhancements of 6 to 20 dB can be obtained easily and are sufficient to establish the absolute phase (sign) of each gamma vector component. Data are presented to show that acceleration sensitivities of 1×10 ^-10/g can be measured with confidence