File:Ship spark transmitter tuned circuit 1921.jpg
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Summary
[edit]DescriptionShip spark transmitter tuned circuit 1921.jpg |
English: The tuned circuit of a marine spark gap transmitter, an obsolete radio transmitter used during the wireless telegraphy era, 1890-1920. This was from a German Telefunken Type D 1.5 kW ship wireless set, which could transmit on wavelengths of 600 - 200 meters (500 - 1500 kHz). It consists of a bank of Leyden jar capacitors (cylinders) connected to a spiral inductor of copper strip through a quenched spark gap (top). It was powered with an alternating current of 10-20 kilovolts from a high voltage transformer. Alterations to image: partially removed aliasing artfacts (crosshatched lines) introduced by scanning the halftone photo using Gimp FFT filter. . |
Date |
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Source | Retrieved August 4, 2013 from Bernard John Leggett (1921) Wireless Telegraphy, with Special Reference to the Quenched-Spark System, E. P. Dutton and Co., New York, fig. 29a facing p. 85 on Google Books |
Author | Bernard John Leggett |
Licensing
[edit]Public domainPublic domainfalsefalse |
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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Annotations InfoField | This image is annotated: View the annotations at Commons |
Quenched spark gap. Consists of multiple metal disks with narrow micrometer gaps between them. In operation the disks rapidly cooled the ionized air, terminating the spark after the energy had been transferred to the antenna, to minimize wasted energy
Oscillation transformer resonates with the capacitors to form the tuned circuit that creates the radio frequency oscillating current. The primary induces current in the secondary that is attached to the antenna.
Leyden jar capacitors connected to the coil through the spark gap, making up the tuned circuit. Charge stored in the capacitors by a high voltage transformer is discharged with each spark, creating an oscillating damped wave.
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current | 11:43, 3 May 2021 | 852 × 1,128 (223 KB) | Materialscientist (talk | contribs) | FFT | |
09:17, 1 November 2015 | 852 × 1,128 (117 KB) | Chetvorno (talk | contribs) | User created page with UploadWizard |
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