Handbook for the use of electricians in the operation and care of electrical machinery and apparatus of the U.S. seacoast defenses (1902)
United States. War Dept, Anderson, George Lucius, 1849-1934 · Washington, Govt. Print. Off. · leaf 184
ings off. 4. To illustrate the working of a board, itis only necessary to take three line drops,/, /, f\ in fig. 178, two plugs, P and P,and twin wire cord 1 and 2, one listeningkey, K, also one ringing key, K, whose but-ton being pressed, throws the magneto, al-ways running on a large board, into… … 177. Gravity Drop. 134 HANDBOOK FOR ELECTRICIANS. The insulated cylinder next the knob connects at the same time the otherconductor with the second main line to the station. 6. Suppose a call comes from station 1— The drop falls, displaying number 1 to the operator. She then inserts either plug, as…
Electric machinery · Searchlights · Coast defenses
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
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