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US2639406A
Expired / Lapsed
US
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Tunable magnetron tube
Assignee: United States, WAR, Secretary of
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Filing: 1946-01-03
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Granted: 1953-05-19
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Expires: 1966-01-03
Abstract
No abstract record available.
Inventors
- 👤 Franzo H Crawford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:53
CPC Classifications
H; H01; H01J; H01J23/00; H01J23/16; H01J23/18; H01J23/20; H01J23/213
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-18 | 1956-11-17 | 1957-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-18 | 1960-11-17 | 1961-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-18 | 1964-11-17 | 1965-05-19 | $7700.00 | Window Closed / Lapsed |