Patent US3053503A successfully refreshed from Google Patents.
Patent US2756286A successfully refreshed from Google Patents.
US2756286A
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Frequency selective signal amplifier
Assignee: Individual
•
Filing: 1948-06-24
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Granted: 1956-07-24
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Expires: 1968-06-24
Abstract
No abstract record available.
Inventors
- 👤 Ford L Johnson
- 👤 Kenneth W Mcload
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:38
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/1638
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-07-24 | 1960-01-23 | 1960-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-07-24 | 1964-01-23 | 1964-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-07-24 | 1968-01-23 | 1968-07-24 | $7700.00 | Window Closed / Lapsed |