US2637779A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crystal filter circuit
Assignee: Collins Radio Co
•
Filing: 1950-11-13
•
Granted: 1953-05-05
•
Expires: 1970-11-13
Abstract
No abstract record available.
Inventors
- 👤 Robert L Craiglow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:33
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/54; H03H9/545
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2222043A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-04 | 1956-11-03 | 1957-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-04 | 1960-11-03 | 1961-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-04 | 1964-11-03 | 1965-05-05 | $7700.00 | Window Closed / Lapsed |