US1753444A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signaling system
Assignee: AT&T Inc
•
Filing: 1926-10-08
•
Granted: 1930-04-08
•
Expires: 1946-10-08
Abstract
No abstract record available.
Inventors
- 👤 Russell S Ohl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:54
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/26
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1933-04-07 | 1933-10-07 | 1934-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1937-04-07 | 1937-10-07 | 1938-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1941-04-07 | 1941-10-07 | 1942-04-08 | $7700.00 | Window Closed / Lapsed |