Toroidal_telephone_loading_coil.jpg
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Summary
Description Toroidal telephone loading coil.jpg |
English:
A loading coil for a 1922 AT&T long distance telephone trunkline between New York and Chicago. It consists of a toroidal iron core with two 0.175 H windings. Each twisted pair in the telephone trunkline is attached to a loading coil. The coils are contained in steel tanks on the telephone pole, immersed in oil. The line required a loading coil every 6000 ft.
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Date | |
Source | Retrieved February 21, 2014 from James J. Pilliod, "Philadelphia-Pittsburgh section of the New York-Chicago cable" in Transactions of the AIEE , American Institute of Electrical Engineers, New York, August 1922, p. 452, fig. 18 on Google Books |
Author | James J. Pilliod |
Licensing
Public domain Public domain false false |
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occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See
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