Intercommunicating telephone set system on bifilar line.

摘要

System for intercommunicating telephone sets on bifilar line including a master circuit (CM) on which an external telephone line (le) is abutted, as well as an internal telephone line (li). To this one, a number of slave circuits (CS) are connected in cascade among them, and to each one of them one of said intercommunicating telephone sets (TL) is abutted.