apparatus for data transmission in duplex with two sons

摘要

A circuit arrangement for providing full duplex data communication over two wires is described. Each station connected to the two wires contains a transmitter and receiver. The receivers are connected across the two lines; a balancing resistor connects one of the two lines to each receiver. The balancing resistors are adapted so that transmitter operation in a given station does not interfere with reception. The receivers produce measuring signals for aiding in the reception of data from other stations. The measuring signals are equal in value to the difference between two currents; the first current is that which flows through a transmitter and the two lines in a given station, and the second current is that which flows through the transmitter and the balancing resistor in a given station.