US3373364A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Standby cathode heating circuit for vacuum tube
Assignee: Griffiths Electronics Inc
•
Filing: 1965-09-23
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Granted: 1968-03-12
•
Expires: 1985-09-23
Abstract
No abstract record available.
Inventors
- 👤 Gerald A Tumarkin
- 👤 Ng Walter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:30
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/52; H03F1/54; H03F1/546
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) | 1971-03-12 | 1971-09-11 | 1972-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-03-12 | 1975-09-11 | 1976-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-03-12 | 1979-09-11 | 1980-03-12 | $7700.00 | Window Closed / Lapsed |