Patent DE376977C successfully refreshed from Google Patents.
Patent US3531722A successfully refreshed from Google Patents.
US3531722A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency monitoring system employing a local oscillator and fixed-tuned monitor
Assignee: FREDERICK W SEIBOLD
•
Filing: 1967-08-11
•
Granted: 1970-09-29
•
Expires: 1987-08-11
Abstract
No abstract record available.
Inventors
- 👤 Frederick W Seibold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:14
CPC Classifications
H; H03; H03L; H03L7/00; H03L7/02; G; G01; G01R; G01R23/00
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1973-09-28 | 1974-03-30 | 1974-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-09-28 | 1978-03-30 | 1978-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-09-28 | 1982-03-30 | 1982-09-29 | $7700.00 | Window Closed / Lapsed |