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Patent US2494657A successfully refreshed from Google Patents.
US2494657A
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US
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Amplifier coupling network
Assignee: Hartford National Bank and Trust Co
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Filing: 1947-02-11
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Granted: 1950-01-17
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Expires: 1967-02-11
Abstract
No abstract record available.
Inventors
- 👤 Haantjes Johan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:53
CPC Classifications
H; H03; H03H; H03H11/00; H03H11/02; H03H11/04; H03H11/12; H03F; H03F1/00; H03F1/42; H03F1/48; H03F1/50
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-01-16 | 1953-07-18 | 1954-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-01-16 | 1957-07-18 | 1958-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-01-16 | 1961-07-18 | 1962-01-17 | $7700.00 | Window Closed / Lapsed |