US2857574A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tunable electrical resonator
Assignee: Hazeltine Research Inc
•
Filing: 1954-12-23
•
Granted: 1958-10-21
•
Expires: 1974-12-23
Abstract
No abstract record available.
Inventors
- 👤 Dean B Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:12
CPC Classifications
H; H01; H01P; H01P7/00; H01P7/06
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-10-20 | 1962-04-21 | 1962-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-10-20 | 1966-04-21 | 1966-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-10-20 | 1970-04-21 | 1970-10-21 | $7700.00 | Window Closed / Lapsed |