extension telephone

As extension of IDN network, ISDN has broken the ambit between the traditional telephone network and data network, expanded the application types and scope of network operation.

综合业务数字网（ISDN）是综合数字网的延伸，它打破了传统电话网和数据网之间的界限，扩展了网络业务的使用类型和范围。

Each fire special use telephone extension telephone Shan Zhan group, telephone jack each Lou Zhan group.

每一消防专用电话分机单占一路, 电话插孔每栋楼占一路.

Application Technology of Cheap to Bring About Half-Automatic Continuation and Extension for Urban Telephone Subscriber Line

实现半自动接续和市话用户线路延伸的廉价实用技术

In view of the fact that the apparatus would undoubtedly be used by the Prime Minister, and that no extension telephone involving an outside line could be permitted,

鉴于首相需要使用这套设备，但它却不允许外线接入，

The system can realize three call mode including single-call, group-call and interrupt-call, in addition each extension telephone can set its address by itself.

系统能够实现单呼、群呼和强插三种通话方式，且每个分机都具有单独设号功能。

The principal application for this extension is at the analogue end points of digital transmission links, especially telephone terminal equipment.

该扩展的主要应用是在数字传输链路的模拟端点，特别是电话终端设备。