Patent US3517223A successfully refreshed from Google Patents.
US3517223A
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US
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Transistor phase shift circuit
Assignee: AT&T Inc
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Filing: 1967-11-17
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Granted: 1970-06-23
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Expires: 1987-11-17
Abstract
No abstract record available.
Inventors
- 👤 Wilmer B Gaunt Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:33
CPC Classifications
H; H03; H03H; H03H11/00; H03H11/02; H03H11/16; H03H11/18; H03H11/04; H03H11/12; H03H11/1213; H03H11/126; H03H11/22
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-06-22 | 1973-12-22 | 1974-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-06-22 | 1977-12-22 | 1978-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-06-22 | 1981-12-22 | 1982-06-23 | $7700.00 | Window Closed / Lapsed |