Terminal transmission equipment (TTE) for the SL undersea lightwave system

the SL transmission terminal equipment (TTE) provides the interface between the inland toll transmission network at 139.264 Mbit/s (CCITT 4th level) and the SL undersea cable on a two working and one standby fiber-pair basis. The TTE provides multiplexing of two 139.264- Mbit/s signal and overhead bits per fiber as well as electrical-to-optical signal conversion. End-to-end maintenance features, such as, order-wire, line performance parameters, alarms, and line regenerator supervisory signaling access are also provided.