Patent US2166439A successfully refreshed from Google Patents.
US2664501A
Expired / Lapsed
US
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Frequency conversion system
Assignee: WILCOX GAY CORP
•
Filing: 1949-08-10
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Granted: 1953-12-29
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Expires: 1969-08-10
Abstract
No abstract record available.
Inventors
- 👤 Glen S Whidden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:26
CPC Classifications
H; H03; H03D; H03D7/00; H03D7/06; H03D7/08; H03B; H03B5/00; H03B5/02; H03B5/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2051177A
Cited
US2144009A
Cited
GB516152A
Cited
US2235816A
Cited
US2284372A
Cited
US2453078A
Cited
US2266670A
Cited
US2441452A
Cited
US2281461A
Cited
US2309031A
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US2472021A
Cited
US2503780A
Cited
US2470425A
Cited
US2508048A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-12-28 | 1957-06-29 | 1957-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-12-28 | 1961-06-29 | 1961-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-12-28 | 1965-06-29 | 1965-12-29 | $7700.00 | Window Closed / Lapsed |