File:Spark transmitter at Ambon Indonesia 1921.png

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Captions

Captions

Spark gap radiotelegraphy transmitter, Ambon, Indonesia, 1920

Summary

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Description
English: A 2.5 kW spark-gap transmitter station operated around 1920 by the Dutch East Indies Co. at Ambon, Indonesia, to communicate with Jakarta. It transmits information by radiotelegraphy, the operator tapped on a switch called a telegraph key turning the transmitter on and off to transmit text messages by Morse code. The transformer charged the Leyden jar capacitors up to a high voltage of 5 - 20 kV, which discharged through the spark gap and coil, creating oscillating currents which were applied to the large wire antenna (not shown), which radiated the energy as radio waves.
Date
Source Retrieved 9 March 2018 from Bernard John Leggett (1921) Wireless Telegraphy, with special reference to the Quenched-Spark System, E. P. Dutton Co., New York, fig. 140, facing p. 280 on Google Books
Author Bernard John Leggett

Licensing

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Public domain
This work is in the public domain in the United States because it was published (or registered with the U.S. Copyright Office) before January 1, 1929.
Public domain works must be out of copyright in both the United States and in the source country of the work in order to be hosted on the Commons. If the work is not a U.S. work, the file must have an additional copyright tag indicating the copyright status in the source country.
Note: This tag should not be used for sound recordings.PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Spark_transmitter_at_Ambon_Indonesia_1921.png
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current17:50, 1 May 2021Thumbnail for version as of 17:50, 1 May 2021976 × 696 (496 KB)Materialscientist (talk | contribs)FFT
10:07, 27 March 2018Thumbnail for version as of 10:07, 27 March 2018976 × 696 (426 KB)Chetvorno (talk | contribs)User created page with UploadWizard

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