US3718873A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phase shifter having at least one t-section lc circuit
Assignee: United States Department of the Army
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Filing: 1971-06-28
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Granted: 1973-02-27
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Expires: 1991-06-28
Abstract
Abstract THE PRESENT INVENTION SETS FORTH DESIGN CRITERIA AND GENERIC LC CIRCUIT CONFIGURATIONS FOR TWO TYPES OF PHASE SHIFTERS. THE FIRST TYPE ACCOMPLISHES VARIABLE PHASE SHIFTING BY EMPLOYING A T-SECTION CIRCUIT USING FIXED INDUCTORS AND VARIABLE CAPACITORS IN THE SERIES LEG OF THE CIRCUIT WHILE A PARALLEL CONNECTION OF FIXED INDUCTOR AND VARIABLE CAPACITOR EXISTS IN THE SHUNT LEG OF THE CIRCUIT. IN THE SECOND TYPE, DIGITAL PHASE SHIFT IS ACCOMPLISHED BY SEQUENTIALLY SWITCHING BETWEEN LOW AND HIGH PASS T-SECTION FILTERS.
Inventors
- 👤 R Garver
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:44
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/18; H01P1/185
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) | 1976-02-27 | 1976-08-28 | 1977-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-27 | 1980-08-28 | 1981-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-27 | 1984-08-28 | 1985-02-27 | $7700.00 | Window Closed / Lapsed |