Auxiliary attenuator arrangement for use in voice-switched speakerphone and method of selectively inserting communication loss in speakerphone paths

摘要

Speech signals appearing at the receiving and transmitting paths of a speakerphone which operates under voice switching, are received at a control circuit. The control circuit issues a control signal which assumes a first level in the event that a signal at the receiving path exceeds a signal at the transmitting path and which assumes a second level if the signal at the receiving path falls below the signal at the transmitting path. Communication loss is inserted in both the receiving and transmitting paths in response to the first level of the control signal, and is eliminated therefrom in response to the second level of the control signal.