Patent FR519666A successfully refreshed from Google Patents.
FR519666A
Expired / Lapsed
FR
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Improvements to electron tubes
Assignee: Westinghouse Lamp Co
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Filing: 1920-02-12
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Granted: 1921-06-14
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Expires: 1940-02-12
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
FR
Data Source
google_patents
Last Synchronized
2026-11-07 15:23
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/163
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