US2549875A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermionic valve circuits
Assignee: Individual
•
Filing: 1947-08-06
•
Granted: 1951-04-24
•
Expires: 1967-08-06
Abstract
No abstract record available.
Inventors
- 👤 Williams Frederic Calland
- 👤 Norman F Moody
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:14
CPC Classifications
H; H03; H03K; H03K21/00; G; G01; G01R; G01R23/00; G01R23/02; H03K3/00; H03K3/02; H03K3/04; H03K3/05; H03K3/06; H03K3/10; H03K4/00; H03K4/06; H03K4/08; H03K4/10; H03K4/12; H03K4/20; H03K4/22; H03K5/00; H03K5/00006
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2114938A
Cited
US2291045A
Cited
US2252457A
Cited
US2405237A
Cited
US2412485A
Cited
US2418364A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-04-23 | 1954-10-23 | 1955-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-04-23 | 1958-10-23 | 1959-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-04-23 | 1962-10-23 | 1963-04-24 | $7700.00 | Window Closed / Lapsed |