Telephone exchange with address receiving relays - has each individual unit reached through two address lines, to which windings of relays are separately connected

摘要

The exchange individual units for reception and/or delivery of signals are equipped with signal receiving and/or transmitting switches connected to common signal circuits. These switching units are made operative by address receivers in the form of relays. Two groups of address lines are provided for control of these address receivers. In order to reach one certain individual unit, one address line in each group is activated. Each of these lines leads to several units, based on the control matrix principle. Windings of two individual address receiving relays are in each individual unit separately connected to the two address lines. The other winding terminals are connected to a fixed opposite potential. Signal receiving and/or transmitting switching units can be activated through two make contacts of the address receiving delays, connected in series.