Patent US2839619A successfully refreshed from Google Patents.
US2839619A
Expired / Lapsed
US
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Pulse amplifier
Assignee: Individual
•
Filing: 1955-04-05
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Granted: 1958-06-17
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Expires: 1975-04-05
Abstract
No abstract record available.
Inventors
- 👤 Johnstone Charles Wilkin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:46
CPC Classifications
H; H03; H03K; H03K5/00; H03K5/01; H03K5/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2712081A
Cited
US2538488A
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US2500756A
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US2686266A
Cited
US2617946A
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US2740835A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-06-16 | 1961-12-16 | 1962-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-16 | 1965-12-16 | 1966-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-16 | 1969-12-16 | 1970-06-17 | $7700.00 | Window Closed / Lapsed |