Ultrasonic technique for the measurement of pressure below atmospheric pressure

This paper deals with the theory, fabrication and test results of an ultrasonic technique which is used to measure vacuum in a container. Ultrasonic transmitter and receiver, working at 40 KHz, are used for conducting the experiments. The sensitivity of measurement is a function of applied voltage to the transmitter. Results on a prototype model are included and relationship between output voltage and pressure is appreciably linear.