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. 1908 Excerpt: ...pull of the magnet. The springs are adjusted until a point is reached when, with the armature placed on the poles, the force of attraction of the magnet is slightly in excess of the tension of the springs. The incoming signals pass through the coils in such a direction as temporarily to weaken the pull of the magnet. ...
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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. 1908 Excerpt: ...pull of the magnet. The springs are adjusted until a point is reached when, with the armature placed on the poles, the force of attraction of the magnet is slightly in excess of the tension of the springs. The incoming signals pass through the coils in such a direction as temporarily to weaken the pull of the magnet. The balance, so lightly set, is thus destroyed and the armature is released. As soon as the initial movement is accomplished--that is, as soon as the slightest space exists between armature and poles--the attractive power of the magnet falls off very rapidly, according to the well-known law. Hence as soon as it is detached, the armature rises with practically the whole force of the springs. In rising, the armature strikes upward the left-hand end of the detent arm P, which is seen in Figs. 101 and 102, and is shown separately in Fig. 106. This left-hand end of P is normally just above the armature with a small space between them. Keyboard.--This (Figs. 100 and 108) is a system of 28 levers mounted at the front of the instrument. The levers are pivoted beneath the table plate, and their front ends form a kind of pianoforte keyboard, in which 14 white alternate regularly with 14 black keys. The back ends of the levers rest normally under the key-pins, two of which, C C, are shown in Fig. 100. The white key at the left is the "letter-blank." The sixth white key is also a blank, and every key bearing a letter also bears a figure or punctuation sign. This second blank key is the "figureblank," and when this is depressed the series of figures comes into use instead of the letter series. The keyboard thus contains 26 letters and 2 blanks, or 28 keys in all. Key-pins--Pin-plate.--A horizontal circular plate of brass B (Figs. 101 and...
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Add this copy of Telegraphic Systems and Other Notes to cart. £54.30, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Santa Clarita, CA, UNITED STATES, published 2016 by Wentworth Press.
Add this copy of Telegraphic Systems and Other Notes to cart. £38.24, good condition, Sold by Wonderland Books rated 1.0 out of 5 stars, ships from Berkeley, CA, UNITED STATES, published 1908 by J. B. Lippincott Co.
