American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 290
to another, apparatuscorresponding to that used in this country is employed, namely, a pole-changer andtransmitter operated by their electromagnets and keys in local circuits. {See t andPC, Fig. 163.) CHAPTER XIII. DUPLEX AND QUADRUPLEX REPEATERS. Although automatic repeaters of the class described… … DUPLEX REPEATERS ARRANGED ON QUARTETTE TABLE. pelting automatically from one wire into another, operate in a more direct andsimple manner than do the single wire, automatic repeaters. 242 AMERICAN TELEGRAPHY. This is explained by the fact that in duplex telegraphy the result is practicallythe same…
Telegraph
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