The Effects of Time Delay and Echoes on Telephone Conversations

A brief history of the problem of echoes and delay in telephone connections is first given. Actual delays involved in typical circuits are shown. This is followed by a discussion of the effects of delay only on typical conversations. The sources of echo in typical telephone connections are then discussed, together with measures which have been taken to reduce echo by improving return loss. Methods of controlling the effects of delayed echo are then summarized; the summary includes a brief introduction to echo suppressors and some of the new problems they introduce