US1971235A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radio receiving system
Assignee: AT&T Inc
•
Filing: 1931-11-28
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Granted: 1934-08-21
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Expires: 1951-11-28
Abstract
No abstract record available.
Inventors
- 👤 Francis X Rettenmeyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:49
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/65; H04H20/76; H04H20/77; H04H40/00; H04H40/18; H04H40/27
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) | 1937-08-20 | 1938-02-19 | 1938-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1941-08-20 | 1942-02-19 | 1942-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1945-08-20 | 1946-02-19 | 1946-08-21 | $7700.00 | Window Closed / Lapsed |