Patent US2694140A successfully refreshed from Google Patents.
US2694140A
Expired / Lapsed
US
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Selection of low interference radio channels
Assignee: AT&T Inc
•
Filing: 1951-11-24
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Granted: 1954-11-09
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Expires: 1971-11-24
Abstract
No abstract record available.
Inventors
- 👤 George W Gilman
- 👤 Kenneth W Pfleger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:20
CPC Classifications
H; H04; H04K; H04K3/00; H04K3/20; H04K3/22; H04K3/224; H04K3/226; H04K2203/00; H04K2203/30; H04K2203/36
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2231806A
Cited
US2137023A
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US2363583A
Cited
US2479701A
Cited
US2384456A
Cited
US2525679A
Cited
US2521696A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-11-08 | 1958-05-10 | 1958-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-11-08 | 1962-05-10 | 1962-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-11-08 | 1966-05-10 | 1966-11-09 | $7700.00 | Window Closed / Lapsed |