A Proposed Current-Noise Index for Composition Resistors

A study of fluctuation voltage generated by dc current flowing in composition resistors has led to a convenient factor for expressing the noisiness of a resistor. This factor, or index, is named "conversion gain" and indicates the efficiency with which a resistor converts applied dc power to noise power, expressed in decibel units. The method of measurement is described, and results are given for various commercial resistors including some film types. The use of conversion gain for quality control testing is discussed. Also, examples are given of the use of conversion gain in computing interference in actual circuits.