The SLC@ 96 carrier system has been developed to bring digital capability to the local loop network, and ultimately it may be a component of a completely integrated digital network. It uses two unique channel banks: one located in the central office to interface to the local switching machine, and the other located remotely in the vicinity of a group of subscribers. The SLC 96 carrier can provide, through the use of different channel units, message telephone service, coin service, special services, and data services. For digital transmission, it interfaces to standard Tllines or optical fibers. The design is patterned after the D4 channel bank, and many of D4 carrier's channel units can be used in the SLC 96 carrier system. The resultant system has the versatility to serve both rapidly growing metropolitan, as well as rural, areas. Features that provide highly reliable service and easy maintenance have been included in the design of the system.

The L5 repeatered line is presented from the viewpoint of a distributed equalization process. Reliable transmission of 10,800 circuits over 4000 miles of coaxial cable with minimum noise is the sole objective of this process. The strategy is to provide equalization in cause‐associated increments that place specific bounds on signal‐level excursions, thereby insuring an ultralinear, low‐noise predictable transmission medium. The individual causes of signal misalignment, both static and dynamic, are examined and the realization of the strategy, which forms a hierarchy of equalizers, is described.

Abstruct-Two major characteristics of the coaxial cable that are of paramount importance in the design of coaxial line repeaters are the nominal cable loss and the variation in the cable loss due to seasonal variations in cable temperature.As a result, there are two types of line repeaters used to equalize for the cable loss characteristics. One is a low-noise ultralinear fixedgain amplifier. It is designated the basic repeater and is used to equalize for the nominal loss of the coaxial cable. The second type, called the regulating repeater, includes a basic repeater plus additional circuitIy which automatically corrects for dynamic variations in cable loss due to temperature.Some of the important design techniques that are used to achieve these low-noise ultralinear repeaters are described. In addition, ananalysis of the steady-state response of a tandem string of regulating repeaters is included. Paper approved by the Associate Editor for Wire Communication of the IEEE Communications Society for publication after presentation at