US2575571A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wave-signal directional coupler
Assignee: Hazeltine Research Inc
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Filing: 1947-05-13
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Granted: 1951-11-20
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Expires: 1967-05-13
Abstract
No abstract record available.
Inventors
- 👤 Harold A Wheeler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 08:49
CPC Classifications
H; H01; H01P; H01P5/00; H01P5/12; H01P5/16; H01P5/18; H01P5/183
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-11-19 | 1955-05-21 | 1955-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-11-19 | 1959-05-21 | 1959-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-11-19 | 1963-05-21 | 1963-11-20 | $7700.00 | Window Closed / Lapsed |