Study of return losses on loaded trunk cables and methods taken to improve them

Return loss as a measure of a circuit's uniformness has been used in the Telephone Industry for many years. It usually determines the amount of gain which may be introduced into a circuit before encountering undesirable conditions of echo or singing. While the toll plant, or long distance circuits, have been of primary interest, today's transmission objectives tend to emphasize the need for accurate analysis of all trunk cables with a view toward their improvement. This paper will review briefly the meaning of return loss, and attempt to acquaint the reader with some of the practical factors encountered in analyzing and improving the return loss of loaded trunk cables.