Telemetric electro-acoustic supervision of heat and power machinery

Abstract A telemetric electro-acoustic method is explained, enabling the discovery of irregularities in the machinery-noise, by hearing, after the general noise level has been reduced to a low level, eliminating the masking effect of the original high noise intensity. In addition, an objective system is proposed, using transducers for vibration as well as for air-borne sound. Continuous recording, the introduction of electric filters and the comparative observation of standard vibration and noise curves, with those produced by the machinery (applying double beam oscillographs, spectral line analysis, etc.) are explained.