Modern practice of the electric telegraph. A handbook for electricians and operators (1872)
Pope, Frank L. (Franklin Leonard), 1840-1895 · New York : D. Van Nostrand · leaf 37
Fio. 10. 52. THE MORSE SIGXAL KEY is shown in fig. 10.* Itconsists of a brass lever, A, four or five inches in length,which is hung upon a steel arbor, G, between adjustableset screws, I) 1), in such a manner as to allow it tamove freely in a vertical direction. This movement,however, is limited in… … THK MORSE, OR AMERICAN TELEGRAPHIC SYSTEM. 29 One wire of the main circuit is connected to themetallic frame of the key, and the other to the anvil, C,which is insulated from the frame. These connectionsarc made by screws passing up through the table frombeneath. The lever is provided with a knob…
Telegraph
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