US3555439A
Expired / Lapsed
US
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Electrical filters
Assignee: Rank Organization Ltd
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Filing: 1968-04-16
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Granted: 1971-01-12
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Expires: 1988-04-16
Abstract
Abstract AN ELECTRIC SIGNAL INCLUDING HIGH AND LOW FREQUENCY COMPONENTS IS (A) FILTERED TO REMOVE THE HIGH FREQUENCIES WITHOUT DISTORTING THE LOW FREQUENCIES, AND (B) DELAYED TO SYNCHRONISE IT, WITHOUT DISTORTION, WITH THE FILTERED SIGNALS. THE FILTERED SIGNAL IS SUBTRACTED FROM THE DELAYED SIGNAL TO PROVIDE A SIGNAL COMPRISING THE UNDISTORED HIGH FREQUENCY COMPONENT.
Inventors
- 👤 Arthur Tisso Starr
- 👤 Thomas Charles Reeve
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:21
CPC Classifications
H; H03; H03H; H03H15/00; H03H11/00; H03H11/02; H03H11/04
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) | 1974-01-11 | 1974-07-13 | 1975-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-11 | 1978-07-13 | 1979-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-11 | 1982-07-13 | 1983-01-12 | $7700.00 | Window Closed / Lapsed |