Electrical engineer's pocket-book: a hand-book of useful data for electricians and electrical engineers (1901)
Foster, Horatio A. (Horatio Alvah), 1858-1913 · New York, D. Van Nostrand co.; London, E.& F.N. Spon, ltd. · leaf 669
her plug in the spring-jack of the subscriber, learns with what number hewants to be connected, then connects one end of a cord from the callingsubscribers jack to the one he called, as the number called for has a jackon every section. The following diagram shows in simple form the connec-tions for… … Ofb This form of board is open to manydefects, and is being replaced by an-other form to be next described. Theseries multiple board, as the above issometimes called, has all the spring-jacks of a subscribers line in series,and a weak spring or a particle ofdust may open-circuit one of thejacks and…
Electrical engineering
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
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