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. The practical telephone handbook and guide to the telephonic exchange . rhaps40 or 50 (as seen in Fig. 463, whichshows a group of 30). A receiveris connected at the exchange endof any one of these call wires, andan operator is continually listeningduring business hours. A sub-scriber of the group has merelyto press a special key or lever(which changes the connection ofhis instrument from his ordinaryline to the call wire) to place him-self in instant communicationwith the operator, to whom hethen gives his own number andthat of the subscriber he wishesFig. 463.—Branch Call Wire to speak with
. The practical telephone handbook and guide to the telephonic exchange . rhaps40 or 50 (as seen in Fig. 463, whichshows a group of 30). A receiveris connected at the exchange endof any one of these call wires, andan operator is continually listeningduring business hours. A sub-scriber of the group has merelyto press a special key or lever(which changes the connection ofhis instrument from his ordinaryline to the call wire) to place him-self in instant communicationwith the operator, to whom hethen gives his own number andthat of the subscriber he wishesFig. 463.—Branch Call Wire to speak with. The operator then joins the ordinary lines of thesetwo numbers by cords, plugs, and switch-jacks, as on anordinary board, enabling the subscribers concerned to ringor speak as they wish. When they have finished their con-versation they press the call-wire key, and tell the operatorto disconnect. The above would appear to be a very simple and rapidsystem of working, subscribers being always withthe operators. Practical difficulties, mainly due to the inter-. ®\—-@
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Keywords: ., bookcentury1900, bookdecade1900, booksubjecttelephone, bookyear19