US3454888A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistorized power amplifier using two series connected transistors driven by an emitter-coupled pair of transistors
Assignee: AT&T Inc
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Filing: 1967-08-23
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Granted: 1969-07-08
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Expires: 1987-08-23
Abstract
No abstract record available.
Inventors
- 👤 Frederick D Waldhauer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 03:12
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/30; H03F3/3083; H03F3/3086; H03F3/3093
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-07-07 | 1973-01-06 | 1973-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-07-07 | 1977-01-06 | 1977-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-07-07 | 1981-01-06 | 1981-07-08 | $7700.00 | Window Closed / Lapsed |