American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 388
split plugs and tubular plugs shown in loop switch diagrams, elsewhere. Theannunciators are connected by wire to the sleeve y; the metal pin 2e^with the hori-zontal jack. The wedges w, w are connected with batteries b, b in the manner shown.Each subscribers circuit, which is a duplicate of that… … At such times it will be seen that the circuit of magnet m, SO, is< open at ep andcp and the transmitter coils c, c are short-circuited by tlie wires via the contacts p pand the transmitter rod, which is connected directly to ground. When a subscriber desires to communicate with another…
Telegraph
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