Henry and Hora's modern electricity; a practical working encyclopedia (1915)
Henry, James. [from old catalog], Hora, Karel Jan, 1881- [from old catalog] joint author · Chicago, Laird & Lee, inc. · leaf 271
ck and plug 218. The jack is an (see A fig. 121) arrangement, bymeans of which, the connection of two subscribers may bemade, by inserting the plug B into its aperture, so that itcomes into contact with the line by touching the spring a.The forward end of the spring a, rests in its normal… … Fig. 121. to the ground. When the plug is inserted into the apertureof the jack, it disconnects the line from the ground bylifting the spring a from the pin b and establishes a con-nection of the other line to the jack where another plug,connected with the former by a flexible cord dt is also…
Electrical engineering
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