File:Sealed cat whisker detector.jpg
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Sealed_cat_whisker_detector.jpg (499 × 499 pixels, file size: 46 KB, MIME type: image/jpeg)
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[edit]DescriptionSealed cat whisker detector.jpg |
English: A galena cat whisker detector from around 1922, an antique radio component used in crystal radio receivers from 1906 to World War 2. It consists of a fine wire attached to an adjustable arm that touches the surface of a crystal of galena (lead sulfide). In this type, common in portable radios, the delicate cat whisker and crystal are sealed inside a glass tube to prevent contamination by dirt and fingerprints. It functioned as a crude semiconductor diode, rectifying the AC radio signal to extract the audio (sound) modulation signal from the radio frequency carrier wave. The galena crystal is embedded in a fusible metal alloy such as Wood's metal in a metal cup in the base of the detector. The cup and the cat whisker are connected to the binding posts, which are used to connect the device with the rest of the receiver. |
Date | |
Source | Retrieved 19 July 2018 from Henry Smith Williams (1922) Practical Radio, Funk and Wagnall's Co., New York, p. 78 on Google Books |
Author | Unknown authorUnknown author |
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[edit]Public domainPublic domainfalsefalse |
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:Sealed_cat_whisker_detector.jpg |
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Date/Time | Thumbnail | Dimensions | User | Comment | |
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current | 17:20, 1 May 2021 | 499 × 499 (46 KB) | Materialscientist (talk | contribs) | FFT | |
02:22, 20 July 2018 | 499 × 499 (26 KB) | Chetvorno (talk | contribs) | User created page with UploadWizard |
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