Telephone line connecting system - has evaluation circuit providing control signal for establishing connections

摘要

Lines connecting transmitters e.g. of telephone systems, are established by means of a reflex junction panel controllable via junction-forming circuits and junction-holding circuits, reversal of the holding circuits effecting energisation of routing relays at the transmitters and opening of the junction-forming circuits. A control voltage derived from the switching on of the junction-forming circuits influences a central supervisory device in such manner that an output signal therefrom connects an evaluation device to the junction-forming circuit, the evaluation device being designed so that a control signal effecting the establishment of the connections is derived from the opening of all the junction-forming circuits.