Noise Level Meter

An instrument which measures the level of continuous noise present in amplifier and/or receiver circuits with reference to a fixed level of signal generated by a separate noise source. It is designed to measure noise levels over a wide band of frequencies including radio and video frequencies, and is normally calibrated in decibels relative to a specified r.M.S. Voltage summation across a specified impedance, or in decibels relative to a specified noise power level. if only audio frequency range, see meter, audio level.