File:Popov coherer radio receiver.jpg
Popov_coherer_radio_receiver.jpg (784 × 385 pixels, file size: 55 KB, MIME type: image/jpeg)
File information
Structured data
Captions
Summary edit
DescriptionPopov coherer radio receiver.jpg |
English: One of the first radio receivers, built by Russian physicist Alexander Popov as a lightning detector in 1894. It is not clear from the source whether this is the original or a recreation. It uses a coherer (top), a glass tube containing metal filings between two electrodes, invented by Edouard Branley in 1890. Radio waves are received by the wire dipole antenna (top) and applied to the coherer electrodes. The radio waves cause the metal powder to stick together (cohere) and decrease the resistance between the coherer electrodes, turning on a DC circuit to ring a bell. Popov improved the coherer by adding a relay, and a mechanical vibrator (electric bell, center) which disturbed the filings, resetting the coherer to its receptive state after each signal had been received. On 25 April 1895 Popov demonstrated the receiver to a meeting of the Russian Physico-Chemical Society at Petersburg University. In Russia Popov is regarded as the inventor of radio, and 25 April is celebrated as Radio Day.. |
Date | |
Source | Retrieved 26 April 2013 from Gustav Partheil 1907 Die drahtlose Telegraphie und Telephonie, Gerdes und Hodel, Berlin, p. 13, fig. 8 on Google Books |
Author | Gustav Partheil |
Licensing edit
Public domainPublic domainfalsefalse |
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.
|
||
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.
|
File history
Click on a date/time to view the file as it appeared at that time.
Date/Time | Thumbnail | Dimensions | User | Comment | |
---|---|---|---|---|---|
current | 08:29, 5 November 2013 | 784 × 385 (55 KB) | Chetvorno (talk | contribs) | User created page with UploadWizard |
You cannot overwrite this file.
File usage on Commons
There are no pages that use this file.
File usage on other wikis
The following other wikis use this file:
- Usage on fr.wikipedia.org