Patent US2721397A successfully refreshed from Google Patents.
US2721397A
Expired / Lapsed
US
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Simulated high frequency radio receiving apparatus for aircraft trainers
Assignee: Curtiss Wright Corp
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Filing: 1951-07-17
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Granted: 1955-10-25
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Expires: 1971-07-17
Abstract
No abstract record available.
Inventors
- 👤 Joseph E Gallo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:48
CPC Classifications
G; G09; G09B; G09B9/00; G09B9/02; G09B9/08; G09B9/26
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1981589A
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US2448544A
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US2366603A
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US2450240A
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US2519233A
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US2559039A
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US2471439A
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US2560527A
Cited
US2685747A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-10-24 | 1959-04-25 | 1959-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-24 | 1963-04-25 | 1963-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-24 | 1967-04-25 | 1967-10-25 | $7700.00 | Window Closed / Lapsed |