Current supply equipment for distance supplied line repeaters - uses phantom circuit of two balanced lines with wire connected to resistors centre tapping

摘要

Repeaters consist of a preequaliser and an active amplifier section in a balanced line. Supply d.c. current is fed in equal parts through a phantom circuit of two balanced lines to the respective repeater. A wire is connected to a centre tapping of two matching resistors connected in parallel to the repeater input. It is split in two by the resistors and carried by transmission line two wires to the output of the next repeater so that a supply d.c. circuit is produced. Two resistors in series with each other are connected in parallel with the output of each repeater and with the input of the active section (2). Their centre tappings are directly connected with each other, so that a second supply d.c. circuit is provided. Voltage drop between a repeater output and the input of the active amplifier section (2) is smaller than voltage drop in the first supply d.c. circuit.