File:Telephone loading coils 1922.jpg
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![File:Telephone loading coils 1922.jpg](https://upload.wikimedia.org/wikipedia/commons/thumb/a/ad/Telephone_loading_coils_1922.jpg/489px-Telephone_loading_coils_1922.jpg?20210503104710)
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[edit]DescriptionTelephone loading coils 1922.jpg |
English: A loading coil for a 1922 AT&T long-distance telephone trunk cable between New York and Chicago. Loading coils prevent signal degradation on long distance lines and are still used in modern telephone systems. It consists of toroidal 0.175 H coils each attached to one of the circuits in the trunkline. 14 toroidal coils are strung on a spindle, shown leaning against the pot. Seven spindles fit in the pot, which is filled with oil. The pot will be mounted on a telephone pole. Loading coils are required at 6000 ft. intervals along the cable. |
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. 591, fig. 19 on Google Books |
Author | James J. Pilliod |
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[edit]Public domainPublic domainfalsefalse |
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This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See this page for further explanation.
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current | 10:47, 3 May 2021 | ![]() | 719 × 882 (237 KB) | Materialscientist (talk | contribs) | FFT |
07:04, 22 February 2014 | ![]() | 747 × 900 (116 KB) | Chetvorno (talk | contribs) | User created page with UploadWizard |
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