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US2438913A
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High-frequency filter structure
Assignee: Unisys Corp
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Filing: 1942-09-02
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Granted: 1948-04-06
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Expires: 1962-09-02
Abstract
No abstract record available.
Inventors
- 👤 William W Hansen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:35
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/20; H01P1/201; H01P1/202
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1935313A
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US2030178A
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US2178299A
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US2127408A
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US2248227A
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US2250090A
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US2253393A
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US2243851A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-04-06 | 1951-10-06 | 1952-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-04-06 | 1955-10-06 | 1956-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-04-06 | 1959-10-06 | 1960-04-06 | $7700.00 | Window Closed / Lapsed |