US2257031A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power amplifier
Assignee: Siemens APP und Maschinen GmbH
•
Filing: 1939-08-19
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Granted: 1941-09-23
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Expires: 1959-08-19
Abstract
No abstract record available.
Inventors
- 👤 Barth Gustav
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:46
CPC Classifications
H; H03; H03F; H03F9/00; H03F9/02; G; G05; G05B; G05B11/00; G05B11/01; G05B11/012; G05B11/016
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) | 1944-09-22 | 1945-03-24 | 1945-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-09-22 | 1949-03-24 | 1949-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-09-22 | 1953-03-24 | 1953-09-23 | $7700.00 | Window Closed / Lapsed |