ULTRASONIC BIOLOGICAL EFFECT EXPOSURE SYSTEM.

An ultrasonic biological effect exposure system was developed to provide experimental data which could be used in assessing the biological risk from exposure to ultrasonic energy. The system can reproduce the ultrasonic signals of medical diagnostic and therapeutic equipment at comparable or greater intensities. Signal synthesis is at low electrical powers (less than 0 dBm) with linear amplification of the signal to the desired level by a high power, broadband amplifier. A minicomputer controls the exposure time and the net electrical power to the ultrasonic transducer assembly through an interface to a programmable frequency synthesizer. The net electrical power is monitored by a dual directional coupler which, in turn, is monitored by the minicomputer with an r. f. digital voltmeter.