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US2447309A
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Tuning indicator system
Assignee: Hazeltine Research Inc
•
Filing: 1945-10-29
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Granted: 1948-08-17
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Expires: 1965-10-29
Abstract
No abstract record available.
Inventors
- 👤 Harold L Blaisdell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:11
CPC Classifications
H; H03; H03J; H03J3/00; H03J3/02; H03J3/12; H03J3/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2164979A
Cited
US2334473A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-08-17 | 1952-02-16 | 1952-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-08-17 | 1956-02-16 | 1956-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-08-17 | 1960-02-16 | 1960-08-17 | $7700.00 | Window Closed / Lapsed |