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Poulsen_tikker_radio_receiver_circuit.png (581 × 482 pixels, file size: 30 KB, MIME type: image/png)
Summary
DescriptionPoulsen tikker radio receiver circuit.png |
English: Schematic diagram of a radio receiver from the first decade of the 1900s using a "tikker", to receive radiotelegraph transmissions. Around 1905, continuous wave (CW) radio transmitters began replacing the previous spark-gap transmitters which generated damped waves. The "tikker" or "ticker" invented by Valdemar Poulsen in 1902 was one of the first devices that could make CW Morse code transmissions audible. It consisted of an interrupter such as a motor driven contact wheel which had metal contacts spaced around its rim, which periodically interrupted the carrier wave from the tuned circuit, producing a tone in the earphones. The tikker was only used for a short time, until Fessenden's heterodyne receiver replaced it around 1913. |
Date | |
Source | Retrieved January 28, 2016 from Elmer Eustice Bucher (1920) The Wireless Experimenter's Manual, The Wireless Press, New York, p. 243, fig. 201 on Google Books |
Author | Elmer Eustice Bucher |
Licensing
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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Captions
Paulsen's tikker radiotelegraph receiver
Items portrayed in this file
depicts
inception
1920
File history
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Date/Time | Thumbnail | Dimensions | User | Comment | |
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current | 08:23, 1 February 2016 | ![]() | 581 × 482 (30 KB) | Chetvorno | User created page with UploadWizard |
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Horizontal resolution | 28.35 dpc |
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Vertical resolution | 28.35 dpc |
File change date and time | 22:25, 28 January 2016 |
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