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File:Marconi spark transmitter on SS Minnetonka 1902.jpg

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Marconi_spark_transmitter_on_SS_Minnetonka_1902.jpg (627 × 591 pixels, file size: 108 KB, MIME type: image/jpeg)

Summary

Description
English: Photo of standard Marconi shipboard spark wireless transmitter in the radio room of the S.S. Minnetonka in 1902. Operating from batteries, it transmitted with a power of 100-200 watts on a frequency of 600 - 1000 kHz. The induction coil (cylinder, right) produced a high voltage which charged the 6 Leyden jar capacitors (center). A spark across the spark gap (right) discharged the capacitors through a spiral air core "oscillation transformer" in the box on the wall, creating oscillating currents. The transformer is connected to an external wire antenna strung between the masts and the power from the oscillating currents is radiated as radio waves. The transmitter transmitted data by wireless telegraphy; the operator taps on the telegraph key (bottom center) turning the transmitter on and off, to spell out text messages in Morse code. British-Italian radio pioneer Guglielmo Marconi invented the first practical radio transmitters and receivers around 1896, and his company, the Marconi Wireless Telegraph Company, dominated marine wireless through World War 1.
Date
Source Retrieved 21 May 2018 from Marillier, H. C. "The development of wireless telegraphy, part 2" in Page's Magazine, Chicago, IL, Vol. 1, No 4, October 1902, p. 387 on Google Books
Author H. C. Marillier

Licensing

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.

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Note: This tag should not be used for sound recordings.PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Marconi_spark_transmitter_on_SS_Minnetonka_1902.jpg
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Marconi shipboard radiotelegraphy transmitter

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1 October 1902Gregorian

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Date/TimeThumbnailDimensionsUserComment
current17:56, 1 May 2021Thumbnail for version as of 17:56, 1 May 2021627 × 591 (108 KB)MaterialscientistFFT
01:37, 22 May 2018Thumbnail for version as of 01:37, 22 May 2018627 × 591 (66 KB)ChetvornoUser created page with UploadWizard

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