File:Spark gap transmitter-Marconi patent 763772 fig 1.png
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Summary
| Description |
English: Spark-gap transmitter circuit from Guglielmo Marconi's controversial patent no. 763772 for a "four circuit" wireless telegraphy radio communication system. The significant innovation of this circuit was the use of two tuned circuits, coupled by a resonant transformer (d,d'), which Marconi called a "jigger". This reduced the bandwidth of the transmitted signal, which enabled it to transmit much further, and reduced interference with transmitters on other frequencies. The receiver also employed a similar resonant transformer design with two tuned circuits, so the combined system was described as a "four circuit" design. This patent was the foundation of the Marconi Company's dominance of the wireless business during the first decades of the 20th century. It was contested by Oliver Lodge, Nikola Tesla, and John Stone Stone as violating their prior patent rights, and became the focus of a long running litigation. It was overturned in 1943 by the US Supreme Court. |
| Date | |
| Source | Retrieved August 14, 2015 from US patent no. 763772 Guglielmo Marconi, Apparatus for wireless telegraphy, filed November 10, 1900; granted June 28, 1904 |
| Author | Guglielmo Marconi |
Licensing
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In general, the contents of United States patents are in the public domain.
In specific cases, patent applicants and holders may claim copyright in portions of those documents. In those specific cases, applicants are required to identify the portions that are protected under copyright, and are additionally required to state the following within the body of the application and patent (see 37 CFR 1.71(d) & (e) and 37 CFR 1.84(s), and MPEP § 608.01(e) & (w) and MPEP § 1512):
The original patent should be checked for the presence of such language before an assumption is made that the contents are in the public domain. (This template can be replaced by {{PD-US-patent-no notice}} in such cases.)
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File history
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 07:05, 15 August 2015 | | 546 × 834 (7 KB) | Chetvorno | User created page with UploadWizard |
