American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 210
r which may correspond to a duplex relay, at a. b is abattery at a distant station in circuit i. The resistances of wires i and 2 are supposedto be equal. Battery b is so arranged that its current coincides in direction with thecurrent from battery b. It is assumed that the electromotive force of… … THEORY DIFFERENTIAL DUPLEX. electromotive force in wire 2 has not been increased, the current in coil 2 remains asin Fig. 141. This excess of current in coil i magnetizes the bar virtually as ifthere were but one coil with a current from one of the batteries flowing in it. Thisaction will be…
Telegraph
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