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US3518549A
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US
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Automatic protection switching system for communication channels
Assignee: Italtel SpA
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Filing: 1965-10-24
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Granted: 1970-06-30
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Expires: 1985-10-24
Abstract
No abstract record available.
Inventors
- 👤 Luigi Sarati
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:49
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/52; H03F1/54; H03F1/542; H04; H04B; H04B1/00; H04B1/74
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2733296A
Cited
US2572912A
Cited
US2892930A
Cited
US3111624A
Cited
US3328697A
Cited
US3268816A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-06-29 | 1973-12-29 | 1974-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-06-29 | 1977-12-29 | 1978-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-06-29 | 1981-12-29 | 1982-06-30 | $7700.00 | Window Closed / Lapsed |