FIELD EXPERIENCES WITH DIGITAL LOOPS.

Digital transmission has been extensively used for several years in the toll network, but its introduction into subscriber loop plant is fairly recent. The initial digital subscriber carrier system in the loop plant in Maine was installed in 1974. It is reported that since then digital carrier systems have been installed in five other exchanges. Use was made of digital subscriber carrier systems as a means to replace a small dial office and to provide for growth facilities in some longer routes. Currently, additional locations are scheduled to be relieved by utilizing digital facilities.