Patent US2502822A successfully refreshed from Google Patents.
US2502822A
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US
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Electron tube coupling circuit
Assignee: AT&T Inc
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Filing: 1942-12-31
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Granted: 1950-04-04
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Expires: 1962-12-31
Abstract
No abstract record available.
Inventors
- 👤 Everett T Burton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:53
CPC Classifications
H; H03; H03H; H03H11/00; H03H11/02; H03H11/32
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) | 1953-04-03 | 1953-10-03 | 1954-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-04-03 | 1957-10-03 | 1958-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-04-03 | 1961-10-03 | 1962-04-04 | $7700.00 | Window Closed / Lapsed |