File:Amateur radio T antenna 1912.png
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![File:Amateur radio T antenna 1912.png](https://upload.wikimedia.org/wikipedia/commons/thumb/c/c1/Amateur_radio_T_antenna_1912.png/635px-Amateur_radio_T_antenna_1912.png?20140312185604)
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[edit]DescriptionAmateur radio T antenna 1912.png |
English: A wire antenna for a home amateur radio station, from a 1912 textbook. It is a type called a T antenna, widely used in medium wave and longwave bands during the wireless telegraphy era before 1930. The vertical wire from the radio transmitter in the attic up to the horizontal wires is the radiating element, while the horizontal "clothesline" wires suspended between two insulating wooden spacers are a capacitive "top-load" that serves to add capacitance to the antenna, increasing the radiated power. In the early en:spark-gap transmitters used until World War 1, the output power was limited by the amount of energy that could be stored in the capacitance of the antenna, so multiwire antennas like this were common. |
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Source | Retrieved November 9, 2013 from Harry Winfield Secor, Sidney Gernsback, Austin Celestin Lescarboura (1912) Wireless Course in Twenty Lessons, Lesson 1, The Electro Importing Co., New York, p. 103, fig. 40 on Google Books |
Author | Harry Winfield Secor, Sidney Gernsback, Austin Celestin Lescarboura |
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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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This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the rule of the shorter term for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.
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current | 18:56, 12 March 2014 | ![]() | 1,364 × 1,288 (164 KB) | Chetvorno (talk | contribs) | User created page with UploadWizard |
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Horizontal resolution | 28.35 dpc |
Vertical resolution | 28.35 dpc |
File change date and time | 18:32, 12 March 2014 |
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