American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 312
e spring-jack. For repeating from one quad set to another, as from a to b, in Fig. 202, a double-end cord, having a full brass plate, r p, ^as in Fig. 202^) on one wedge, and a half plateH p, on the other wedge, is used; the full plate h p making contact, but leaving in theresistance ;^,as at p. In… … CHAPTER XVL COMBINATION DUPLEX SYSTEMS, ETO. THE EDISON-SMITH DUPLEX. This duplex is arranged to operate with battery at one end only. It may beclassed as a combination of the Stearns duplex and the polar duplex. Such aduplex is occasionally of utility when it is not feasible to place a battery at…
Telegraph
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