US2640922A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency response system
Assignee: General Electric Co
•
Filing: 1949-07-26
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Granted: 1953-06-02
•
Expires: 1969-07-26
Abstract
No abstract record available.
Inventors
- 👤 Elmer D Mcarthur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:31
CPC Classifications
H; H03; H03D; H03D9/00; H03D9/02; H03D9/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2151118A
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US2419208A
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US2413939A
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US2420892A
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US2498548A
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US2442606A
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US2522563A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-01 | 1956-12-01 | 1957-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-01 | 1960-12-01 | 1961-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-01 | 1964-12-01 | 1965-06-02 | $7700.00 | Window Closed / Lapsed |