| 摘要 |
PURPOSE:To prevent a public circuit from being used surreptitiously by providing an identification number which is applied to only both a key station and its slave equipment and registering the identification number in the master equipment optionally. CONSTITUTION:The key station and slave equipment are connected by connectors 4 and 5 and the special recognition number, etc., are written through the key station in addition to the extension number and trunk line telephone number of the subordinate equipment. Those numbers are stored in the memory circuit MEMO incorporated in the key station device at the same time. When a public telephone circuit is used through the slave equipment, a signal corresponding to the discrimination number is sent out and compared with the stored discrimination number by the key station, and the external line or extension is connected only when they are identical. Further, the various recognition numbers registered in the memory MEMO of the key station are freely erasable. |
