Patent EP0111134A1 successfully refreshed from Google Patents.
US2428295A
Expired / Lapsed
US
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Thermionic valve amplifier circuit arrangement
Assignee: EMI Ltd
•
Filing: 1944-04-21
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Granted: 1947-09-30
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Expires: 1964-04-21
Abstract
No abstract record available.
Inventors
- 👤 Scantlebury Gordon Si Pengelly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:13
CPC Classifications
H; H03; H03C; H03C1/00; H03C1/16; H03F; H03F3/00; H03F3/42; H03F3/44
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2358428A
Cited
US2310342A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-09-29 | 1951-03-31 | 1951-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-09-29 | 1955-03-31 | 1955-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-09-29 | 1959-03-31 | 1959-09-30 | $7700.00 | Window Closed / Lapsed |