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US2774872A
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Phase shifting circuit
Assignee: AT&T Inc
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Filing: 1952-12-17
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Granted: 1956-12-18
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Expires: 1972-12-17
Abstract
No abstract record available.
Inventors
- 👤 Howson Louis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:37
CPC Classifications
H; H03; H03L; H03L7/00; H03L7/06; H03L7/08; H03L7/081; H03B; H03B27/00; H03H; H03H11/00; H03H11/02; H03H11/16; H03H11/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2406309A
Cited
US2527523A
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US2605425A
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US2526353A
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US2568412A
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US2610297A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-12-18 | 1960-06-18 | 1960-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-12-18 | 1964-06-18 | 1964-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-12-18 | 1968-06-18 | 1968-12-18 | $7700.00 | Window Closed / Lapsed |