File:Marconi radiotelegraphy receiver circuit US patent 763772 fig 2.png

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    Summary

    Description
    English: Circuit of Guglielmo Marconi's inductively-coupled coherer radiotelegraphy receiver, from his controversial US patent 763772 Guglielmo Marconi, Apparatus for wireless telegraphy, fig.2], filed 10 November 1900, granted 28 June 1904. In this patent Marconi claimed credit for the "4 circuit" radio system, which had already been patented by Nikola Tesla, Oliver Lodge, and John Stone Stone. This patent gave Marconi rights to virtually all radiotelegraphy in England and the US. In 1943 the US Supreme Court invalidated this patent.

    Labeled parts:

    A vertical antenna
    B battery to operate relay
    c1, c2 chokes to prevent electrical transients created by relay from triggering coherer
    E earth connection, a metal plate buried in the ground
    f1 optional metal plate at top of antenna
    g1 loading coil to adjust antenna to resonance with tuned circuit
    g2 inductors
    h primary tuning capacitor
    h1 secondary tuning capacitor
    j1, j2 resonant transformer
    R relay, which controls paper tape recorder (not shown)
    T coherer, which becomes conductive when exposed to radio wave from antenna
    Date
    Source Retrieved 3 June 2025 from US Patent 763772 Guglielmo Marconi, Apparatus for wireless telegraphy, filed November 10, 1900, granted June 28, 1904, fig.2 on Google Patent
    Author Guglielmo Marconi

    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, 1931.
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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_radiotelegraphy_receiver_circuit_US_patent_763772_fig_2.png
    Public domain

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    Captions

    Inductively coupled radiotelegraphy receiver 1900

    Items portrayed in this file

    depicts

    schematic diagram

    radio receiver

    inception

    10 November 1900Gregorian

    File history

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    current00:51, 4 June 2025Thumbnail for version as of 00:51, 4 June 2025523 × 665 (20 KB)wikimediacommons>ChetvornoUploaded a work by Guglielmo Marconi from Retrieved 3 June 2025 from [https://patents.google.com/patent/US763772 US Patent 763772 Guglielmo Marconi, Apparatus for wireless telegraphy, filed November 10, 1900, granted June 28, 1904, fig.2] on Google Patent with UploadWizard

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