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US2169212A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radio transmitting system
Assignee: Individual
•
Filing: 1937-01-16
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Granted: 1939-08-15
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Expires: 1957-01-16
Abstract
No abstract record available.
Inventors
- 👤 Edwin H Armstrong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:53
CPC Classifications
H; H03; H03C; H03C3/00; H03C3/02
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) | 1942-08-14 | 1943-02-13 | 1943-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-08-14 | 1947-02-13 | 1947-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-08-14 | 1951-02-13 | 1951-08-15 | $7700.00 | Window Closed / Lapsed |