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US3219873A
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US
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Microwave electron discharge device having annular resonant cavity
Assignee: Northrop Grumman Space and Mission Systems Corp
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Filing: 1961-09-01
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Granted: 1965-11-23
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Expires: 1981-09-01
Abstract
No abstract record available.
Inventors
- 👤 Kaufman Irving
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:40
CPC Classifications
H; H01; H01J; H01J25/00; H01J25/78
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2418735A
Cited
US2463617A
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US2444073A
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US2408437A
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US2489082A
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US2827592A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-11-22 | 1969-05-24 | 1969-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-22 | 1973-05-24 | 1973-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-22 | 1977-05-24 | 1977-11-23 | $7700.00 | Window Closed / Lapsed |