US2469569A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Point contact negative resistance devices
Assignee: AT&T Inc
•
Filing: 1945-03-02
•
Granted: 1949-05-10
•
Expires: 1965-03-02
Abstract
No abstract record available.
Inventors
- 👤 Russell S Ohl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:39
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/16; H04B3/18; H03; H03B; H03B7/00; H03B7/02; H03B7/06; H03C; H03C7/00; H03C7/02; H03F; H03F3/00; H03F3/04; H03F3/10; H03F3/12; H10; H10D; H10D99/00; H10P; H10P95/00; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49014; Y10T29/49117
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) | 1952-05-09 | 1952-11-08 | 1953-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-05-09 | 1956-11-08 | 1957-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-05-09 | 1960-11-08 | 1961-05-10 | $7700.00 | Window Closed / Lapsed |