The practical telephone handbook and guide to the telephonic exchange (1906)
Poole, Joseph · New York, Macmillan Co. · leaf 222
of the jacksbeing readily accessible in case of faults. The shorter the length of wire used the better, both onaccount of lower cost and because the static capacity of thecable is rather high. The wires used should not impede access to other parts ofthe board, and they should occupy as little space… … Fig. 222 1| inches wide by ^ths of an inch thick, each containing 63wires, made up in 21 sets of three, each set being twisted andkept together by a few cotton threads. One wire of each setis used for the a line, one for the b line, and the third for thetest line. All the b wires are coloured…
Telephone
Internet Archive · Northeastern University Library · Public Domain Mark 1.0. Free to use for anything.
