ELECTRONIC WEIGHING APPARATUS UTILIZING SURFACE ACOUSTIC WAVES

摘要

A weighing apparatus includes a SAW oscillator and a "push oscillator" to force the SAW oscillator into a desired mode of operation. A SAW temperature oscillator and a thermistor are also provided. The frequency of the "push oscillator" is made immune to temperature changes by generating it via a mixer mixing the SAW temperature oscillator with an adjustable fixed frequency oscillator. Long term stability of the SAW temperature oscillator is achieved by periodic calibration with the thermistor.