Protection against undesirable insects or animals - is provided by emission of particular modulated or unmodulated ultrasonic frequency

摘要

An electronic noise or sound emitter enables vertebrates or non-vertebrates to be attracted or repelled without destroying them. This is particularly useful for humans or other animals for repelling insects by modulating the ultrasonic sound. An electronic emitter circuit comprises a transmitter (1) with a sound emitter (2). The transmission frequency is determined by the type of animal to be repelled. This also determines whether or not the audible or inaudible sound frequency should be modulated continuously. The sound emitter is a miniature loudspeaker or tweeter and the components are of the integrated circuit type or discrete components as required for the application. Similarly the power supply is integrated with the circuit or is independent.