Patent US2876402A successfully refreshed from Google Patents.
US2086601A
Expired / Lapsed
US
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Modulating system
Assignee: AT&T Inc
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Filing: 1934-05-03
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Granted: 1937-07-13
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Expires: 1954-05-03
Abstract
No abstract record available.
Inventors
- 👤 Robert S Caruthers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:04
CPC Classifications
H; H03; H03C; H03C1/00; H03C1/52; H03C1/54; H03C1/56; H03C1/58
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) | 1940-07-12 | 1941-01-11 | 1941-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1944-07-12 | 1945-01-11 | 1945-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1948-07-12 | 1949-01-11 | 1949-07-13 | $7700.00 | Window Closed / Lapsed |