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US2666818A
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US
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Transistor amplifier
Assignee: AT&T Inc
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Filing: 1951-09-13
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Granted: 1954-01-19
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Expires: 1971-09-13
Abstract
No abstract record available.
Inventors
- 👤 Shockley William
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:39
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/30; H03F3/3066; H03F3/3067; H03F3/3069; H03F3/3071; H03F3/42
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2524035A
Cited
US2541322A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-01-18 | 1957-07-20 | 1958-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-01-18 | 1961-07-20 | 1962-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-01-18 | 1965-07-20 | 1966-01-19 | $7700.00 | Window Closed / Lapsed |