Patent US2729396A successfully refreshed from Google Patents.
US2021638A
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Amplifier
Assignee: G USESOJUZNOJE OBJEDINENJE ELE
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Filing: 1932-09-08
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Granted: 1935-11-19
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Expires: 1952-09-08
Abstract
No abstract record available.
Inventors
- 👤 Paul N Ramlau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:57
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/62; H03F3/64; H04; H04B; H04B3/00; H04B3/02; H04B3/36
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) | 1938-11-18 | 1939-05-20 | 1939-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1942-11-18 | 1943-05-20 | 1943-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1946-11-18 | 1947-05-20 | 1947-11-19 | $7700.00 | Window Closed / Lapsed |