A proximitor is an electronic device that generates a radio frequency (RF) signal using an oscillator circuit. It also processes the RF signal to extract usable data using a demodulator circuit. A proximitor is often used in conjunction with a proximity probe to measure the displacement of a target surface.
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Thanks to a bit of research performed by Sir Humphry Davy for the British Navy, we have a technology known as "cathodic protection." First developed to keep the copper hulls of British naval ships from corroding, this technology has been applied to protecting everything from oilrigs to gas pipelines to telephony cabinets. By keeping the cabinet frame at a more positive voltage than ground, corrosion is reduced and the life of the equipment is increased. Who would have guessed?