Fault location by pulses in PCM system transmission line - uses two connections made in each repeater between its two parts

摘要

Loops are consecutively formed in repeaters on reception of a locating signal. This occurs when a localing signal with an address is sent out from both supervising end stations. The loop is closed between the output of a repeater responding to the address of the locating signal in the one transmission direction, and the repeater decision part input is connected to the equaliser output in the opposite direction. The regenerators are cross-connected in pairs (411, R25) and (R12, R24) etc.