The practical telephone handbook and guide to the telephonic exchange (1906) (14752988921)

Identifier: practicaltelepho00pool (find matches)

Title: The practical telephone handbook and guide to the telephonic exchange

Year: 1906 (1900s)

Authors: Poole, Joseph

Subjects: Telephone

Publisher: New York, Macmillan Co.

Contributing Library: Northeastern University, Snell Library

Digitizing Sponsor: Boston Library Consortium Member Libraries

Text Appearing Before Image:

SMALL SWITCH-BOARDS iSi convenient type of small switch-board used for C.B. privatebranch extensions. It is intended to stand on a desk or a table.

Text Appearing After Image:

thus allowing the attendant to carry on clerical work, and yetbe always ready to answer a call, and thus ensure more promptattention than is met with, with ordinary wall sets. 182 PRACTICAL TELEPHONE HANDBOOK The instrument shown is a six-line board, intended for twoexchange lines and four extensions; similar instruments aremade for four lines (one exchange and three extensions) andfor ten lines (three exchange and seven extensions). Thecalling indicators for the exchange lines are 1000w tubular(as shown on the left of the second row), and those for theextensions are 500w eye-ball signals, shown in the same row. Two rows of keys, similar to combined ringing and listeningkeys, are used for making the connections, the upper positionsand the lower positions of the upper row of keys being usedfor this purpose, whilst the lower position of the lower rowis used for signalling—by generator in the case of the extensions,and by connecting a 750w-retardation coil across the loop forthe exchan

the practical telephone handbook and guide to the telephonic exchange 1906 book illustrations telephone high resolution images from internet archive

1906

Northeastern University, Snell Library

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public domain