Patent US2325688A successfully refreshed from Google Patents.
Patent US2569000A successfully refreshed from Google Patents.
US2569000A
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Frequency selective circuit
Assignee: Automatic Electric Laboratories Inc
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Filing: 1945-03-24
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Granted: 1951-09-25
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Expires: 1965-03-24
Abstract
No abstract record available.
Inventors
- 👤 Hadfield Bertram Morton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:00
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/01; H03H7/06; H03H7/17; H03H7/1741; H03H7/175; H03H7/1775; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/1638; H04J; H04J1/00; H04J1/02; H04J1/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1546427A
Cited
US1736814A
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US1902031A
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US2096874A
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US2265826A
Cited
US2264151A
Cited
US2449412A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-09-24 | 1955-03-26 | 1955-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-09-24 | 1959-03-26 | 1959-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-09-24 | 1963-03-26 | 1963-09-25 | $7700.00 | Window Closed / Lapsed |