File:Loupiote radio 1915.jpg
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Size of this preview: 501 × 600 pixels. Other resolutions: 200 × 240 pixels | 573 × 686 pixels.
Original file (573 × 686 pixels, file size: 214 KB, MIME type: image/jpeg)
Summary
| Description |
Français : Loupiote. Brevet français n°452657, octobre 1915. Triode militaire TM, douille en cuivre.
English: Early French military triode vacuum tube patent no. 452657, October 1915. The triode was invented by American engineer Lee De Forest in 1906, who held the rights, but in 1912 he let his French patent rights lapse due to lack of a $125 fee. The French government manufactured hundreds of thousands of these sturdy tubes, called the Loupiote, during World War 1. The tube consists of an evacuated glass bulb containing three electrodes: a heated filament, a fine horizontal tungsten wire, surrounded by a concentric helix of wire called the grid, surrounded by a concentric metal cylinder called the plate. |
| Date | |
| Source | Own work Scanné par F1jmm |
| Author | Photo d'un inconnue, anonyme. Unknown |
Licensing
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 | This file is an original and may be obsolete for general use, but is kept for historical or archival use. As such, it should not be modified or deleted except to correct upload or technical errors. Any modified versions or replacements of this image should be uploaded with a different file name. |
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 15:59, 26 March 2012 | | 573 × 686 (214 KB) | wikimediacommons>F1jmm |
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