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Patent US2467299A successfully refreshed from Google Patents.
US2467299A
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US
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High-frequency transmission system
Assignee: AT&T Inc
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Filing: 1942-11-12
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Granted: 1949-04-12
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Expires: 1962-11-12
Abstract
No abstract record available.
Inventors
- 👤 Espenschied Lloyd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:50
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; G; G01; G01S; G01S1/00; G01S1/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1638925A
Cited
US1771148A
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US1750668A
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US1945952A
Cited
US2134716A
Cited
US2169374A
Cited
US2333688A
Cited
US2301929A
Cited
US2400309A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-04-11 | 1952-10-11 | 1953-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-04-11 | 1956-10-11 | 1957-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-04-11 | 1960-10-11 | 1961-04-12 | $7700.00 | Window Closed / Lapsed |