Patent US2820951A successfully refreshed from Google Patents.
US2820951A
Expired / Lapsed
US
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Attenuator
Assignee: Northrop Grumman Space and Mission Systems Corp
•
Filing: 1953-03-17
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Granted: 1958-01-21
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Expires: 1973-03-17
Abstract
No abstract record available.
Inventors
- 👤 Ernest A Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:34
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/22; H01P1/23
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2197123A
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US2286428A
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US2402948A
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US2436427A
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US2629079A
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DE806150C
Cited
US2534437A
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US2670461A
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US2611094A
Cited
US2645758A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-20 | 1961-07-22 | 1962-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-20 | 1965-07-22 | 1966-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-20 | 1969-07-22 | 1970-01-21 | $7700.00 | Window Closed / Lapsed |