Proximity switch

摘要

A proximity switch or detector is disclosed herein having an oscillator circuit for establishing a radio frequency field about an antenna so that the presence of an object or agent in close proximity to the antenna causes the oscillator to become loaded and to cease oscillations. A voltage comparator senses a change of voltage from the oscillator and triggers a bistable circuit. A power-up or setting circuit primes the bistable circuit to be responsive to the trigger signal from the voltage comparator which, in turn, actuates an output driver circuit incorporating a light emitting diode network operably coupled to a load plug interconnecting with a suitable electrical appliance intended to be actuated by the presence of the object or agent.