Patent US2720133A successfully refreshed from Google Patents.
US2720133A
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US
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Apparatus for controlling frequency change
Assignee: RCA Corp
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Filing: 1954-09-22
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Granted: 1955-10-11
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Expires: 1974-09-22
Abstract
No abstract record available.
Inventors
- 👤 Morgan Adolph Raymond
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:50
CPC Classifications
G; G10; G10H; G10H1/00; G10H1/02; G10H1/06; G10H1/14
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) | 1958-10-10 | 1959-04-11 | 1959-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-10 | 1963-04-11 | 1963-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-10 | 1967-04-11 | 1967-10-11 | $7700.00 | Window Closed / Lapsed |