Modern practice of the electric telegraph : a handbook for electricians and operators (1874)
Pope, Frank L., 1840-1895 · New York : D. Van Nostrand · leaf 95
Make the length to be tested as short as possible,and have all the instruments in circuit taken out. Se-lect a good wire, similar, if possible, to the one it isrequired to test, Both these wires must then be con-nected together in a loop, at the nearest available sta-tion beyond the fault, without… … M GOOD WIRE + BAD WIRE F J Fig. 51. Connect one end of the loop to the + pole of thebattery E, and the other to one of the galvanometerwires at M. Connect also the + pole of the batterywith the resistance coils, R, at N, and the — pole ofthe battery to the key, K, and common terminal, a, ofthe…
Telegraph
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