US2536617A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct current negative feedback amplifier
Assignee: Individual
•
Filing: 1945-02-27
•
Granted: 1951-01-02
•
Expires: 1965-02-27
Abstract
No abstract record available.
Inventors
- 👤 Barton L Weller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:01
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/34; H03F1/36; H03F3/00; H03F3/34; H03F3/36
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1915440A
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US2033963A
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US2224699A
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US2202522A
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US2162412A
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US2173426A
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US2297543A
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US2245671A
Cited
US2401779A
Cited
US2431335A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-01 | 1954-07-03 | 1955-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-01 | 1958-07-03 | 1959-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-01 | 1962-07-03 | 1963-01-02 | $7700.00 | Window Closed / Lapsed |