Intercom transmission device

摘要

An intercom transmission device in which feedback whistling and echos due to acoustic couplings are avoided by the fact that the transmission of a number of subfrequency bands is suppressed in one transmission direction whilst the subfrequency bands located between these subfrequency bands are suppressed in the other transmission direction. Application for audio, video conferences, hands-free talking devices for telephone or videophone, intercom systems, long-distance connections. <IMAGE>