Patent US4011982A successfully refreshed from Google Patents.
Patent US3566291A successfully refreshed from Google Patents.
US3566291A
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US
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Assignee: Individual
•
Filing: 1969-04-07
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Granted: 1971-02-23
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Expires: 1989-04-07
Abstract
Abstract TWO SUCCESSIVE DIFFERENTIAL AMPLIFIER STAGES HAVE A SIGNAL INPUT SIMULTANEOUSLY APPLIED THERETO, A FREQUENCY SELECTIVE INVERSE FEEDBACK CIRCUIT CONNECTED TO THE FIRST STAGE, AND THE FIRST STAGE OUTPUT ALSO BEING APPLIED TO THE SECOND DIFFERENTIAL AMPLIFIER STAGE.
Inventors
- 👤 Ira B Tice Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:33
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/181; H03F3/183; H03F1/00; H03F1/34; H03F1/347; H03H; H03H11/00; H03H11/02; H03H11/04; H03H11/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-22 | 1974-08-24 | 1975-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-22 | 1978-08-24 | 1979-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-22 | 1982-08-24 | 1983-02-23 | $7700.00 | Window Closed / Lapsed |