SF system: Shore terminal facilities and fault location

A special shore terminal transmission facility has been developed for the SF Cable System. The multiplex portion differs from similar domestic plant in that the frequency allocation follows international standard, and can operate with 8-kHz as well as conventional 4-kHz spaced message channels. High reliability is achieved through duplication of equipment combined with added failure detection circuitry and protection switching. Additional features include broadband flexible equalization capability to optimize transmission performance, a separate 4-channel order wire, and automatic pilot measuring equipment. From the point of view of physical design, two departures from conventional practice are the use of shorter than normal bay frameworks and enclosures to cover them. both of which are compatible with foreign design practice. Newly designed test equipment enables monitoring undersea performance and fault locating from the shore terminal. Inclusion of a supervisory oscillator in each repeater is a major change from previous submarine cable systems.