US3566312A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switchable filter network
Assignee: VIDAR CORP
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Filing: 1967-05-25
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Granted: 1971-02-23
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Expires: 1987-05-25
Abstract
Abstract A FILTER SWITCHABLE BETWEEN THOMSON AND BUTTERWORTH CHARACTERISTICS WHERE TWO OF THE INDUCTORS OF THE FILTER ARE MAINTAINED CONSTANT AND THE SWITCHING IS ACCOMPLISHED BY CHANGING THE VALUES OF THREE CAPACITORS AND THE LOAD RESISTANCE. THE INDUCTOR DISSIPATION FACTOR IS USED AS A COMMON PARAMETER AND ITS VALUE ADJUSTED TO CAUSE THE INDUCTOR RATIOS BETWEEN THE TWO CHARACTERISTICS TO BE EQUAL. THEREAFTER BY APPLICATION OF THIS RATIO AS AN IMPEDANCE SCALING FACTOR TO THE BUTTERWORTH CHARACTERISTICS, THE INDUCFOR VALUES ARE EQUALIZED NECESSITATING ONLY A CHANGE IN THE CAPACITORS VALUES AND THE LOAD RESISTANCE VALUE TO SWITCH BETWEEN THE TWO CHARACTERISTICS.
Inventors
- 👤 John C Mcdonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:30
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/01; H03H7/0153
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 |