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电话伴侣和分机电话＠史保和电话伴侣和分机电话史保和本文介绍的电话伴侣具有以下４大优点：１．安装方便电话伴侣的大小和普通电话接线盒差不多，采用二线安装，只要代替接线盒装在电话机的输入端就行了。安装时注意２根电话进线有极性区别。两部分机之间的距离可达３００ｍ。...
Phone companion and extension phone @ Shi Bao and phone companion and extension phone Shi Bao and this phone companion has the following four major advantages: 1. Easy to install Telephone companion size and ordinary telephone terminal box is almost the same, the use of second-line installation, as long as the terminal box instead of wiring installed in the phone’s input on the line. Pay attention to the installation of two phones into the line polarity difference. The distance between two machines can reach 300m. ...