Patent US2489313A successfully refreshed from Google Patents.
US2489313A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency modulation discriminator
Assignee: International Standard Electric Corp
•
Filing: 1947-03-08
•
Granted: 1949-11-29
•
Expires: 1967-03-08
Abstract
No abstract record available.
Inventors
- 👤 Louis W Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:29
CPC Classifications
H; H03; H03D; H03D3/00; H03D3/02; H03D3/22
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) | 1952-11-28 | 1953-05-30 | 1953-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-11-28 | 1957-05-30 | 1957-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-11-28 | 1961-05-30 | 1961-11-29 | $7700.00 | Window Closed / Lapsed |