| 摘要 |
PURPOSE:To perform main wire originating control by the common control unit below, by providing the common control unit in the private telephone exchange unit which is not provided with the central office line trunk, in the telephone exchange newwork where two or more private telephone sets are connected mutually by the private line. CONSTITUTION:When 9 is dialed in the telephone set of extension EXT in the side of private telephone exchange unit PAX having no central office line trunk, the dial signal is transmitted to repeater trunk TLT-B in the side of private telephone set PBX, which has the central office line trunk, through repeater trunk TLT-A by the operation of common control unit M. Simultaneously, originating register OR detects this transmission to release trunk TLT-A forcedly. Next, when the number other than 9 is dialed, register OR is self-released after detection and abandons monitor after that. As a result, main wire originating control can be performed by control unit M of unit PAX. |
