US2306435A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency compression
Assignee: AT&T Inc
•
Filing: 1941-01-17
•
Granted: 1942-12-29
•
Expires: 1961-01-17
Abstract
No abstract record available.
Inventors
- 👤 Robert E Graham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:24
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/18; H04B; H04B1/00; H04B1/66; H04B1/662; H04L; H04L25/00; H04L25/38; H04L25/40; H04L25/49; H04N; H04N7/00; H04N7/12; H04N7/127
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) | 1945-12-28 | 1946-06-29 | 1946-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-12-28 | 1950-06-29 | 1950-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-12-28 | 1954-06-29 | 1954-12-29 | $7700.00 | Window Closed / Lapsed |