COMBINED SUPPLY VOLTAGE CONNECTION AND CALL A.C. VOLTAGE GENERATOR AND CONNECTION FOR ANALOG TELEPHONE RECEIVER STATIONS IN EXTENSION INSTALLATIONS

摘要

The invention relates to a circuit arrangement for a combined supply voltage connection and call a.c. voltage generator and connection for analog telephone receiver stations in extension installations. The purpose is to make such a circuit arrangement as simply as possible with electronic components. This is attained in that two current paths are formed between earth and supply voltage potential which lead via the telephone receiver station and apply differing potential thereto if they are switched through by a control unit. In the inoperative position only one current path is switched through. In the call position, both current paths are alternately switched through at the call frequency or blocked. For use in analog telephone receiver stations in extension installations.