ARRANGEMENT WITH A FORK CIRCUIT FOR THE TWO-WIRE-FOUR-WIRE TRANSITION IN PCM-TIME MULTIPLEX SYSTEMS.

摘要

A hybrid circuit arrangement for a telecommunication system includes a transformer having a first and a second partial winding connected to a two-wire line. Third and fourth partial windings having a grounded junction are coupled to a receiving branch and a transmitting branch of a four-wire transmission line, respectively. A power supply bridge having a resultant supply resistor and a supply capacitor is inserted between the first two partial windings. The total inductance of these windings equals the supply capacitor value times the squared supply resistor value. An ohmic load resistor terminating the receiving branch has a resistance according to a specific relationship depending on the ratio of turns of the third partial winding divided by those of the first and second partial windings. Finally, there is provided a quadripole network connected by a first input to the fourth partial winding, by a second input to the receiving branch; by a first output to the transmission line, and by a second output to ground. This network composed of a RC-network is designed such that signal portions of a signal received from the receiving branch of the transmission line supplied to the network directly and across the third and fourth partial windings in a phase-shifted condition are superimposed for cancellation.