A Fluidic System for Measuring Current in Bridge Wires

摘要

A fluidic system for sensing current and transmitting this information is being developed to measure current induced in electronic circuits by radiofrequency electromagnetic radiation. The system consists of two temperature-sensitive flueric oscillators, one of which is heated by the current to be measured while the other produces a reference signal. The beat frequency which results from summing the signals from the two oscillators is amplified with flueric proportional amplifiers and transmitted acoustically out of the radiation environment. The breadboard system can measure direct currents up to 100-mA. Currents of 18 mA were detected with a sensitivity of 1 Hz/mA. In the present system, two amplifiers per meter of length were required to transmit the signal. (Author)