In the pulse induction technology, we don't need two distinct coils, transmitter and receiver, but only a single coil as both transmitter and receiver or more coils working together for same purpose. This technology sends shorts pulses of current through a coil wire. Every burst or pulse creates or generates a brief magnetic field. When the burst gets its end, a collapse of magnetic field happens and results a sharp electrical spike. This spike lasts a few microseconds and causes another current to run through the coil. When the Metal Detector is over a metal object, the pulse generates an opposite magnetic field in the object.