Patent US2568855A successfully refreshed from Google Patents.
US2568855A
Expired / Lapsed
US
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Vacuum tube and circuit therefor
Assignee: RCA Corp
•
Filing: 1946-12-06
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Granted: 1951-09-25
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Expires: 1966-12-06
Abstract
No abstract record available.
Inventors
- 👤 Clarence W Hansell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:36
CPC Classifications
H; H01; H01J; H01J21/00; H01J21/02; H01J21/06; H01J21/065
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1079250A
Cited
US1182291A
Cited
US1873722A
Cited
US1858275A
Cited
US1987328A
Cited
US2390659A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-09-24 | 1955-03-26 | 1955-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-09-24 | 1959-03-26 | 1959-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-09-24 | 1963-03-26 | 1963-09-25 | $7700.00 | Window Closed / Lapsed |