Patent US2773977A successfully refreshed from Google Patents.
US2773977A
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Communications system checking apparatus
Assignee: TDK Micronas GmbH
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Filing: 1951-03-08
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Granted: 1956-12-11
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Expires: 1971-03-08
Abstract
No abstract record available.
Inventors
- 👤 Robert W Hale
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:52
CPC Classifications
B; B61; B61L; B61L7/00; B61L7/06; B61L7/08; B61L7/088; H; H03; H03F; H03F1/00; H03F1/52; H03F1/54
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1662877A
Cited
US1749444A
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US2280420A
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US2277469A
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US2280421A
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US2433281A
Cited
US2459105A
Cited
US2501091A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-12-11 | 1960-06-11 | 1960-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-12-11 | 1964-06-11 | 1964-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-12-11 | 1968-06-11 | 1968-12-11 | $7700.00 | Window Closed / Lapsed |