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US2590104A
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Direct-coupled amplifier
Assignee: United States Department of the Interior
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Filing: 1950-11-03
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Granted: 1952-03-25
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Expires: 1970-11-03
Abstract
No abstract record available.
Inventors
- 👤 Howard L King
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:34
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/42; H03F3/44
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2428295A
Cited
US2329073A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-03-25 | 1955-09-24 | 1956-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-03-25 | 1959-09-24 | 1960-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-03-25 | 1963-09-24 | 1964-03-25 | $7700.00 | Window Closed / Lapsed |