Telegraph engineering : a manual for practicing telegraph engineers and engineering students (1922)
Hausmann, Erich, 1886- · New York : D. Van Nostrand Company · leaf 377
rrents in their coils are as small as 2 to15 microamperes.* Signals are sent either manually or by means of auto-matic transmitters such as described in § i of Chap. IV.Fig. 9 shows a cable key with removable contact levers.Automatic transmission by means of perforated tapesresults in greater speed… … SUBMARINE TELEGRAPHY 363 4. Speed of Signalling. — From the foregoing expres-sions it will be seen that the received current is a functionof U^ consequently the time required to establish a givencurrent at the far end varies inversely with h or directly
Telegraph
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