Patent US2491669A successfully refreshed from Google Patents.
US2491669A
Expired / Lapsed
US
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Ultra high frequency attenuator
Assignee: AT&T Inc
•
Filing: 1945-04-16
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Granted: 1949-12-20
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Expires: 1965-04-16
Abstract
No abstract record available.
Inventors
- 👤 Harry R Larson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:12
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/22; H01P1/222
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2151157A
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US2197123A
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US2395851A
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US2337934A
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US2376785A
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US2407267A
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US2358462A
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US2441598A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-19 | 1953-06-20 | 1953-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-19 | 1957-06-20 | 1957-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-19 | 1961-06-20 | 1961-12-20 | $7700.00 | Window Closed / Lapsed |