US2639371A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wave-guide isolation coupling system
Assignee: AT&T Inc
•
Filing: 1950-01-25
•
Granted: 1953-05-19
•
Expires: 1970-01-25
Abstract
No abstract record available.
Inventors
- 👤 Wallace C Babcock
- 👤 Harry W Nylund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:14
CPC Classifications
H; H01; H01P; H01P3/00; H01P3/16; H01P5/00; H01P5/08; H04; H04B; H04B3/00; H04B3/52
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1912794A
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US2155508A
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US2158875A
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US2313850A
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FR881161A
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US2503549A
Cited
US2427098A
Cited
US2393218A
Cited
US2463297A
Cited
US2535251A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-18 | 1956-11-17 | 1957-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-18 | 1960-11-17 | 1961-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-18 | 1964-11-17 | 1965-05-19 | $7700.00 | Window Closed / Lapsed |