GB1468122A - Device for converting acoustic energy into electrical energy and vice versa - Google Patents

Abstract

1468122 Microphone/receiver arrangement H PEIKER 27 Feb 1975 [1 March 1974] 8316/75 Heading H4J Transducer arrangement, particularly for use in a sound recording and reproduction system or a transmitter receiver, has two electroacoustic transducers and a record reproduce switch connected so that in the record or transmit mode one of the transducers is used as a full frequency range microphone while in the reproduce or receive mode the microphone is used to reproduce the upper frequency range of the reproduced signal and the other transducer is used to reproduce the lower frequency range. As described, Fig. 2, a housing 1 is divided into two sections by a partition 16 with the microphone 5 mounted in one section, and a reproducer 8 mounted in the other section. The microphone is directional and has a conventional front sound aperture 6 and rear slots 7 to provide a required directional characteristic The reproducer has a pressure chamber 14 leading to a portion 4 of the housing forming a resonator having sound output slots 9. Switches 10 are mounted on the housing to effect changeover between record and replay and to make the microphone 5 operate as high frequency reproducer during replay. The record replay switch can be arranged to uncover, or cover, slots 7 to either vary the directional characteristics or to bring into effect a resonant chamber fed by the transducer. The volume of chamber 4 can be adjustable, e.g. by making the housing telescopic. In an alternative form, Fig. 3 (not shown), the reproducer 8 has a re-entrant horn (15) arranged to feed to the cavity 4 and indicator lamps are mounted on the front surface of the housing over the sound input to the microphone.