Patent US2233751A successfully refreshed from Google Patents.
US2233751A
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US
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Frequency variation indicator circuit
Assignee: RCA Corp
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Filing: 1938-01-14
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Granted: 1941-03-04
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Expires: 1958-01-14
Abstract
No abstract record available.
Inventors
- 👤 Stuart W Seeley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:15
CPC Classifications
H; H03; H03J; H03J7/00; H03J7/02; H03J7/04; H03J7/042; G; G01; G01R; G01R25/00; H03D; H03D3/00; H03D3/02; H03D3/06; H03D3/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1944-03-03 | 1944-09-02 | 1945-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-03-03 | 1948-09-02 | 1949-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-03-03 | 1952-09-02 | 1953-03-04 | $7700.00 | Window Closed / Lapsed |