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US2854531A
Expired / Lapsed
US
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Direct-voltage amplifier
Assignee: US Philips Corp
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Filing: 1954-07-29
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Granted: 1958-09-30
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Expires: 1974-07-29
Abstract
No abstract record available.
Inventors
- 👤 Reijnders Joseph Lodewij Maria
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:46
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/34; H03F3/36; H03F1/00; H03F1/26; H03F1/28; H03F3/26; H03F3/28
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2079655A
Cited
US2125719A
Cited
US2228080A
Cited
US2383345A
Cited
US2603720A
Cited
US2543940A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-09-29 | 1962-03-31 | 1962-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-29 | 1966-03-31 | 1966-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-29 | 1970-03-31 | 1970-09-30 | $7700.00 | Window Closed / Lapsed |