Counting translation in telephone junction - device keys DC voltage applied to junction line wire

摘要

The telephone junction device controls the counting pulse generation beginning and end, and keys a d.c. voltage at a specified rate. When the called subscriber puts his receiver down, a signal e.g. flickering clearing signal, is evaluated by a switch becoming operative with a delay. A switching element controlled by this switch is inserted in the control wire passing through the counting translation. It clears the connection. A divider element in the dialling transmission of the control line connects the calling subscriber to the next dialling stage when he fails to hang up after the clearing signal, while releasing the called subscriber. The dialling input is simultaneously finished. The divider enables an additional function to be automatically carried out.