File:Ducretet-Popov spark gap transmitter.png
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Summary
[edit]DescriptionDucretet-Popov spark gap transmitter.png |
English: Early spark-gap tramsmitter manufactured by Eugene Ducretet between 1897 and 1904 for wireless telegraphy communication. Labeled parts are: (O) Spark gap mounted in box to muffle its noise, (Bo) Induction coil, (I) Interrupter for induction coil, (M) Oil-break telegraph key, (P) Antenna wire, (T) Ground wire (i,i') High voltage terminals of coil |
Date | |
Source | Retrieved March 13, 2010 from Domenico Mazzotto (1906) Wireless Telegraphy and Telephony", Whittaker and Co., London, p. 285, fig. 214 on Google Books |
Author | Unknown. The engraving is signed "E. Ducretet, Paris", indicating it was probably taken from the catalog of Eugene Ducretet, a Paris manufacturer of scientific equipment, who died 1944. |
Licensing
[edit]Public domainPublic domainfalsefalse |
This work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 70 years or fewer. 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. | |
This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights. |
https://creativecommons.org/publicdomain/mark/1.0/PDMCreative Commons Public Domain Mark 1.0falsefalse
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current | 15:57, 5 December 2014 | 1,218 × 811 (503 KB) | Chetvorno (talk | contribs) | 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 | 22:55, 13 March 2010 |