DIGITAL COMMUNICATIONS SYSTEM

摘要

A communication system comprising a connecting line and stations connected thereto, each station having free access to the connecting line. In a station which requests or has access, a transmitting stage and a receiving stage are both connected to the line, the output impedance of the transmitting stage on the supply of a predetermined logic value being temporarily increased to at least the order of magnitude of the characteristic impedance of the line, and a detector which is coupled to an output of the receiving stage producing a detection signal which switches off the transmitting station when the receiving stage receives a value which differs from the predetermined logic value.