Patent US2070590A successfully refreshed from Google Patents.
US1935966A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amplifier
Assignee: FOX CASE Corp
•
Filing: 1929-08-31
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Granted: 1933-11-21
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Expires: 1949-08-31
Abstract
No abstract record available.
Inventors
- 👤 Whiting Donald Fairfax
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:52
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/181
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) | 1936-11-20 | 1937-05-22 | 1937-11-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-11-20 | 1941-05-22 | 1941-11-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-11-20 | 1945-05-22 | 1945-11-21 | $7700.00 | Window Closed / Lapsed |