Telegraph Engineering; A Manual for Practicing Telegraph Engineers and Engineering Students

Telegraph Engineering; A Manual for Practicing Telegraph Engineers and Engineering Students

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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. 1915 edition. Excerpt: ...the flange on D. Signal lever L does not fall immediately, because it is momentarily held by pin b or b' carried on the driving wheel. If during this short test interval the line circuit is uninterrupted, a current will flow through the succession magnet and its armature A will be attracted, consequently keeping locking pin / to the left and clear of signal lever L. As pin b passes the downwardly-projecting hook of the signal lever, this lever will fall and the roller R will engage the teeth of the signal wheel, since catch T is pushed to the left when the first tooth on the signal wheel reaches roller R, and is kept in this position until the complete signal is transmitted by means of the notched wheel beneath W and, for a time during each revolution, by lever L itself. While the signal lever is in its lower position, pin / banks against its left end in order to keep lever E clear of the signal lever during the intervals when the line circuit is opened at C and the succession magnet is deprived of current. After the signal wheel has revolved four times slot p' will be in position for pawl P to fall into it, which action arrests the motion of the mechanism. The engagement of pin b' with the right-hand end of the signal lever raises roller R from the signal wheel and causes the contacts C to be closed. If, when the signal box is pulled, another is transmitting its signal over the same line, the succession magnet will be deprived of current at some instant during the brief period that the signal lever is held up by pin b or b', and consequently, spring 5 is enabled to pull lever E away from the magnet. Locking pin I then prevents the signal lever from bearing on W, and causes contacts C to be kept closed. As the normal line current, when'traversing...
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Product details

  • Paperback | 90 pages
  • 189 x 246 x 5mm | 177g
  • Miami Fl, United States
  • English
  • black & white illustrations
  • 1236606337
  • 9781236606334