The practical telephone handbook and guide to the telephonic exchange (1906)
Poole, Joseph · New York, Macmillan Co. · leaf 317
Fig. 292.—Testing Shoe to the main frame, but need not be quite so large, as it is onlynecessary to provide for the lines actually to be fitted on theswitch-board. It should, however, be built for the full capacityat first, as it is difficult to enlarge after installation. The ter-minal tabs on the… … Fig. 293.—Scale \ Fig. 294 horizontally, and provide for three wires per line. A sectionalview is shown in Fig. 293, and a side elevation in Fig. 294. On the vertical side similar sections of terminal tabs areused, but four tabs are provided for each line instead of three. The jumper wire or cable…
Telephone
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