Patent US2162744A successfully refreshed from Google Patents.
US2162744A
Expired / Lapsed
US
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Amplifier
Assignee: AT&T Inc
•
Filing: 1937-01-07
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Granted: 1939-06-20
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Expires: 1957-01-07
Abstract
No abstract record available.
Inventors
- 👤 Harold M Owendoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:22
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/34; H03F1/36
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) | 1942-06-19 | 1942-12-19 | 1943-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-06-19 | 1946-12-19 | 1947-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-06-19 | 1950-12-19 | 1951-06-20 | $7700.00 | Window Closed / Lapsed |