Patent US2921224A successfully refreshed from Google Patents.
US2921224A
Expired / Lapsed
US
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Traveling wave tube amplifier
Assignee: AT&T Inc
•
Filing: 1954-12-06
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Granted: 1960-01-12
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Expires: 1974-12-06
Abstract
No abstract record available.
Inventors
- 👤 Ping K Tien
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:56
CPC Classifications
H; H01; H01J; H01J25/00; H01J25/34; H01J25/36; H01J25/38
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2512468A
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US2654047A
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FR993156A
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US2725499A
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US2751561A
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US2773213A
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FR1053556A
Cited
US2811673A
Cited
US2846613A
Cited
US2809321A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-01-11 | 1963-07-13 | 1964-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-11 | 1967-07-13 | 1968-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-11 | 1971-07-13 | 1972-01-12 | $7700.00 | Window Closed / Lapsed |