US3370247A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Harmonic notch filter
Assignee: United States Department of the Navy
•
Filing: 1964-07-24
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Granted: 1968-02-20
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Expires: 1984-07-24
Abstract
No abstract record available.
Inventors
- 👤 Benjamin F Hoffman
- 👤 Sr Ronald W Carruthers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:12
CPC Classifications
H; H03; H03H; H03H11/00; H03H11/02; H03H11/04; H03H11/12; H03H11/1295
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
101 words
THE COMBINATION IN A HARMONIC NOTCH FILTER FOR FILTERING OUT UNDESIRED HARMONICS FROM SUPPRESSED CARRIER CONTROL SIGNALS, COMPRISING A TWIN T NOTCH FILTER HAVING A RESISTIVE PORTION AND A REACTIVE PORTION, A UNITY GAIN AMPLIFIER CONNECTED TO THE OUTPUT OF SAID TWIN T NOTCH FILTER, A RESISTOR CONNECTED TO THE INPUT OF SAID TWIN T NOTCH FILTER FOR PROVIDING A RELATIVELY HIGH INPUT IMPEDANCE AT FREQUENCIES ABOVE THE NOTCH FREQUENCY, A FIRST CAPACITOR CONNECTED TO THE OUTPUT OF SAID AMPLIFIER AND TO THE RESISTIVE PORTION OF SAID TWIN T NOTCH FILTER, A FIRST RESISTOR CONNECTED TO THE OUTPUT OF SAID AMPLIFIER,
Claim 2
Dependent Claim
101 words
THE COMBINATION IN A HARMONIC NOTCH FILTER FOR FILTERING OUT UNDESIRED HARMONICS FROM SUPPRESSED CARRIER CONTROL SIGNALS, COMPRISING A TWIN T NOTCH FILTER HAVING A RESISTIVE PORTION AND A REACTIVE PORTION, A UNITY GAIN AMPLIFIER CONNECTED TO THE OUTPUT OF SAID TWIN T NOTCH FILTER, A RESISTOR CONNECTED TO THE INPUT OF SAID TWIN T NOTCH FILTER FOR PROVIDING A RELATIVELY HIGH INPUT IMPEDANCE AT FREQUENCIES ABOVE THE NOTCH FREQUENCY, A FIRST CAPACITOR CONNECTED TO THE OUTPUT OF SAID AMPLIFIER AND TO THE RESISTIVE PORTION OF SAID TWIN T NOTCH FILTER, A FIRST RESISTOR CONNECTED TO THE OUTPUT OF SAID AMPLIFIER,
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) | 1971-02-19 | 1971-08-21 | 1972-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-02-19 | 1975-08-21 | 1976-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-02-19 | 1979-08-21 | 1980-02-20 | $7700.00 | Window Closed / Lapsed |