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US2875331A
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US
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Switching tube circuit with auxiliary load energized by self-bias developed at gating grid
Assignee: Zenith Electronics LLC
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Filing: 1952-11-17
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Granted: 1959-02-24
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Expires: 1972-11-17
Abstract
No abstract record available.
Inventors
- 👤 John G Spracklen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:12
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/04; H04N5/12; H04N5/126; H04N5/44; H04N5/52; H04N5/53
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2157534A
Cited
US2211860A
Cited
US2576093A
Cited
US2565486A
Cited
US2649542A
Cited
US2684404A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-02-23 | 1962-08-25 | 1963-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-02-23 | 1966-08-25 | 1967-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-02-23 | 1970-08-25 | 1971-02-24 | $7700.00 | Window Closed / Lapsed |