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US2853647A
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Tunable cavity resonator electron discharge device
Assignee: Northrop Grumman Systems Corp
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Filing: 1954-03-24
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Granted: 1958-09-23
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Expires: 1974-03-24
Abstract
No abstract record available.
Inventors
- 👤 Charles V Litton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:57
CPC Classifications
H; H01; H01J; H01J23/00; H01J23/16; H01J23/18; H01J23/20; H01J23/213; H01J23/207
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2432571A
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US2523122A
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GB630110A
Cited
US2484643A
Cited
US2659025A
Cited
US2623194A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-09-22 | 1962-03-24 | 1962-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-22 | 1966-03-24 | 1966-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-22 | 1970-03-24 | 1970-09-23 | $7700.00 | Window Closed / Lapsed |