Noise from induction regulators

AN IMPORTANT PREREQUISITE to the study of noise in induction regulators is the establishment of a method for making quantitative noise measurements. Surroundings have a very great effect on the values of sound intensity; thus for consistent results all sound measurements should be made under identical conditions as regards not only background noises but also surfaces in the vicinity. Induction regulators, however, are usually difficult to handle and it is therefore quite inconvenient to move them to a place suitable for making sound measurements.