INDUCTION LOOP

For the dubbing process of replacing voices for a motion picture, see Automated dialogue replacement. An induction loop is a simple coil wire transceiver. One use of an induction loop is in inductive loop detection where the coil is used to detect metal objects. Applications for this include vehicle detection at traffic lights and car parks in Parking Guidance and Information systems, use in metal detectors, etc. The principle of operation is a changing inductance which changes the frequency of an oscillator of which the inductive loop forms a part. It is also used in hearing aids for people who have hearing loss (here also known as teleloop).
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