Telephone exchange switching panel - has individually allocated subscriber lines with signal source supplying indicating and control signals

摘要

Telephone exchanges have switching panels at whose line side subscriber lines have individually allocated subscriber circuits, and at least one subscriber station is connected to each line. Central control is provided with a signal source supplying indicating and control signals. The signal source can be connected through a collecting wire to individual subscriber circuits, each of which has switching elements which can be controlled by a control unit through addresses allocated to these circuits. They respond to separate signals from the control unit and cause the connection of the collecting wire to the subscriber station connected to the corresponding subscriber circuit.