This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1896 Excerpt: ... of relay RV This operates the sounder &, which in its turn repeats the signals into the (circuit. The repetition of these outgoing signals in the relay H2, would cause the circuit on the incoming side to open at its local contact, if the extra magnet r2, were not coincidently demagnetized by the action of the ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1896 Excerpt: ... of relay RV This operates the sounder &, which in its turn repeats the signals into the (circuit. The repetition of these outgoing signals in the relay H2, would cause the circuit on the incoming side to open at its local contact, if the extra magnet r2, were not coincidently demagnetized by the action of the repeating sounder S, opening the circuit. Consequently, the outgoing signals are unable to disturb the line on the incoming side. Fig. 100, shows a Milliken repeating relay. Here J/J are the main-line magnets, with the main retractile spring S and E, the extra or local magnets with the extra retractile spring s. The connection of the apparatus will be readily followed from an examination of the preceding figure. The greatest length of circuit usually operated out of New York city, by repeaters, is to Galveston, Tex., a total length of line of 1,800 miles, through three repeaters, but it is possible to thus operate from New York to San Francisco, or even for a greater distance, as many as six repeaters being sometimes employed on one line. CHAPTER XI. HIGH-SPEED TELEGRAPHY. The ordinary Morse apparatus, in which hand signalling is employed, is capable of dealing with telegraphic traffic up to a certain number of messages per hour, depending upon the speed of transmission, which, as we have seen, under practical conditions, is limited to about thirty words per minute. When the traffic between two cities exceeds what can be handled in this way on a single wire, it is necessary to adopt one of the following plans; viz., to employ more wires, equipping each with Morse apparatus; to resort to machine transmission instead of hand transmission j or to adopt some form of multiplex transmission, whereby more than a single message can be simultaneously sent ...
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