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US2419219A
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Phase responsive circuits
Assignee: Sperry Gyroscope Co Inc
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Filing: 1943-05-25
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Granted: 1947-04-22
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Expires: 1963-05-25
Abstract
No abstract record available.
Inventors
- 👤 Charles W Johnstone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:06
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/02; G01S13/06; G01S13/42; G01S13/422; G01R; G01R25/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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GB406903A
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US2092081A
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US2178074A
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US2231929A
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US2227598A
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US2263377A
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US2285038A
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US2328985A
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US2318197A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-04-21 | 1950-10-21 | 1951-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-04-21 | 1954-10-21 | 1955-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-04-21 | 1958-10-21 | 1959-04-22 | $7700.00 | Window Closed / Lapsed |