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Patent US2264197A successfully refreshed from Google Patents.
US2264197A
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US
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Thermionic amplifier
Assignee: Associated Electric Laboratories Inc
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Filing: 1940-05-17
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Granted: 1941-11-25
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Expires: 1960-05-17
Abstract
No abstract record available.
Inventors
- 👤 Hadfield Bertram Morton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:55
CPC Classifications
H; H03; H03K; H03K6/00; H03K6/02; H03F; H03F3/00; H03F3/26; H03F3/28
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) | 1944-11-24 | 1945-05-26 | 1945-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-11-24 | 1949-05-26 | 1949-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-11-24 | 1953-05-26 | 1953-11-25 | $7700.00 | Window Closed / Lapsed |