The practical telephone handbook and guide to the telephonic exchange (1906)
Poole, Joseph · New York, Macmillan Co. · leaf 93
nograph.The single instrument weighs but If ounces, and the pairwith steel wire 4J ounces. In spite of its lightness andconvenience, however, it is not now much used, as it has notproved so efficient as expected. Operators1 Head-Gear Receivers.—These are used to allowexchange operators to have both… … Fig. 58 RECEIVERS IN GENERAL USE 7i and Fig. 60 aDother, provided with an elastic rubber bandand buckle. Loud-Speaking Receiver.—Fig. 61. This is used for com- ; M ™ n^ I -mm ■P ■> * Fig. 59 munication between offices in the same building, so that callsmay be made without any call bell being…
Telephone
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