American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 256
atio of 3 to I in current strength. Hence in each case, with and without Stummresistance, the proportion of current to main line is 3 to i with key closed and openrespectively. TEEMIJ^TAL COI^NECTIOI^S. W. U. QUADRUPLEX. In Fig. 170 are shown the terminal connections of the Western Union… … 214 AMERICAN TELEGRAPHY. Smith condenser; cc are the boxes containing the 600 ohm coils; SP is the 3-point switch for putting line to ground at the desk; sc is the spark-coil withresistance equal to internal resistance of long end of the battery; se is the short end,le the long end of the main…
Telegraph
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