Electro-acoustic transducers and intercommunication systems for aircraft

The paper is a review of audio-frequency communication instruments and techniques used in military aircraft during the war years. It indicates also the purpose and trend of further developments in this field. A brief exposition is first given of the mechanism of speech communication in and from noisy locations, and of the requirements. thereby imposed on the design of transducers and audio circuits. The practical application of these considerations in aircraft equipment is discussed; details are given of instruments used in the Royal Air Force. Telephone distribution problems in aircraft intercommunication and radio installations are outlined, and a brief description is given of systems proposed for future Service and civil aircraft.