US2557009A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective amplifier system
Assignee: RCA Corp
•
Filing: 1947-10-08
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Granted: 1951-06-12
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Expires: 1967-10-08
Abstract
No abstract record available.
Inventors
- 👤 Ellison S Purington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:07
CPC Classifications
H; H03; H03G; H03G9/00; H03G9/02; H03G9/04; H03G9/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1931596A
Cited
US2148030A
Cited
US2173426A
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US2261335A
Cited
US2262846A
Cited
US2245365A
Cited
US2363985A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-06-11 | 1954-12-11 | 1955-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-06-11 | 1958-12-11 | 1959-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-06-11 | 1962-12-11 | 1963-06-12 | $7700.00 | Window Closed / Lapsed |