Patent US3519945A successfully refreshed from Google Patents.
US3519945A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for replacing all or part of a faulty amplifier
Assignee: AT&T Inc
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Filing: 1967-09-05
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Granted: 1970-07-07
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Expires: 1987-09-05
Abstract
No abstract record available.
Inventors
- 👤 Richard E Lawson
- 👤 Charles C Willhite
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:02
CPC Classifications
H; H03; H03K; H03K9/00; H03K9/06; H03F; H03F1/00; H03F1/52; H03F1/526
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) | 1973-07-06 | 1974-01-05 | 1974-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-06 | 1978-01-05 | 1978-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-06 | 1982-01-05 | 1982-07-07 | $7700.00 | Window Closed / Lapsed |