Two-wire operation of n carrier systems

The san francisco BAY area, like many other metropolitan areas, has had a tremendous population increase in a very short period of time. More people mean more industry and more homes. The demand for telephone circuits to give these customers the service they desire has created a cable and conduit problem. Short-haul carrier systems have made great strides toward the relief of this problem, but even these have been only a partial answer. The purpose of this paper is to describe an experiment made by The Pacific Telephone and Telegraph Company for further utilization of existing cable plant to meet this rapidly increasing demand for service.