US3369189A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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Assignee: United States Department of the Navy
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Filing: 1964-07-24
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Granted: 1968-02-13
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Expires: 1984-07-24
Abstract
No abstract record available.
Inventors
- 👤 Benjamin F Hoffman
- 👤 Robert L Konigsberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:50
CPC Classifications
H; H03; H03H; H03H11/00; H03H11/02; H03H11/04; H03H11/12; H03H11/1295
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
148 words
A COMBINATION, IN A VARIABLE FEEDBACK NOTCH FILTER COMPRISING A FIRST RESISTOR, A SECOND RESISTOR CONNECTED IN SERIES WITH SAID FIRST RESITOR, A FIRST CAPACITOR, A SECOND CAPACITOR CONNECTED IN SERIES WITH SAID FIRST CAPACITOR, SAID FIRST AND SECOND CAPACITORS BEING CONNECTED IN ELECTRICAL PARALLELISM WITH SAID FIRST AND SECOND RESISTORS, A GROUND LINE, A UNITY GAIN AMPLIFIER CONECTED TO SAID SECOND RESISTOR AND SAID SECOND CAPACITOR, AND FEEDBACK MEANS INCLUDING A PAIR OF SERIES CONNECTED FEEDBACK CAPACITORS CONNECTED BETWEEN THE OUTPUT OF SAID AMPLIFIER AND SAID GROUND LINE IN ELECTRICAL PARALLELISM WITH A PAIR OF SERIES CONNECTED FEEDBACK RESISTORS AND THE OUTPUT OF SAID AMPLIFIER FOR FEEDING BACK A PREDETERMINED PORTION B1 OF THE OUTPUT SIGNAL FROM SAID AMPLIFIER TO THE JUNCTION OF SAID FIRST AND SECOND RESISTORS AND A PREDETERMINED PORTION B2 OF SAID AMPLIFIER OUTPUT SIGNAL TO THE JUNCTION OF SAID FIRST AND SECOND CAPACITORS.
Claim 2
Dependent Claim
148 words
A COMBINATION, IN A VARIABLE FEEDBACK NOTCH FILTER COMPRISING A FIRST RESISTOR, A SECOND RESISTOR CONNECTED IN SERIES WITH SAID FIRST RESITOR, A FIRST CAPACITOR, A SECOND CAPACITOR CONNECTED IN SERIES WITH SAID FIRST CAPACITOR, SAID FIRST AND SECOND CAPACITORS BEING CONNECTED IN ELECTRICAL PARALLELISM WITH SAID FIRST AND SECOND RESISTORS, A GROUND LINE, A UNITY GAIN AMPLIFIER CONECTED TO SAID SECOND RESISTOR AND SAID SECOND CAPACITOR, AND FEEDBACK MEANS INCLUDING A PAIR OF SERIES CONNECTED FEEDBACK CAPACITORS CONNECTED BETWEEN THE OUTPUT OF SAID AMPLIFIER AND SAID GROUND LINE IN ELECTRICAL PARALLELISM WITH A PAIR OF SERIES CONNECTED FEEDBACK RESISTORS AND THE OUTPUT OF SAID AMPLIFIER FOR FEEDING BACK A PREDETERMINED PORTION B1 OF THE OUTPUT SIGNAL FROM SAID AMPLIFIER TO THE JUNCTION OF SAID FIRST AND SECOND RESISTORS AND A PREDETERMINED PORTION B2 OF SAID AMPLIFIER OUTPUT SIGNAL TO THE JUNCTION OF SAID FIRST AND SECOND CAPACITORS.
References Cited (Backward Citations)
US2441567A
Cited
US2987678A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-02-12 | 1971-08-14 | 1972-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-02-12 | 1975-08-14 | 1976-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-02-12 | 1979-08-14 | 1980-02-13 | $7700.00 | Window Closed / Lapsed |