Patent US2806257A successfully refreshed from Google Patents.
Patent US3218618A successfully refreshed from Google Patents.
US3218618A
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US
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Magnetic reading apparatus for demodulating a recorded frequency modulated signal
Assignee: RCA Corp
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Filing: 1962-01-30
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Granted: 1965-11-16
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Expires: 1982-01-30
Abstract
No abstract record available.
Inventors
- 👤 Warren Henry Ray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:42
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/02; G11B20/06
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
105 words
APPARATUS FOR DEMODULATING A FREQUENCY MODULATED SIGNAL RECORDED ALONG A PATH ON A RECORD COMPRISING, A SINGLE MAGNETIC HEAD SIGNAL RESPONSIVE MEANS DISPOSED ALONG SAID PATH FOR PICKING UP SAID RECORDED SIGNAL AT POSITIONS SPACED FROM EACH OTHER BY A DISTANCE APPROXIMATELY EQUAL TO AN INTEGRAL MULTIPLE OF THE WAVELENGTH OF SAID RECORDED SIGNAL AND FOR SIMULTANEOUSLY PRODUCING BY ITSELF A RESULTING SIGNAL CONDITION CORRESPONDING TO THE MAGNITUDE AND SENSE OF THE DIFFERENCE BETWEEN THE SIGNALS PICKED UP AT SAID SPACED POSITIONS, AND MEANS RESPONSIVE TO SAID RESULTING SIGNAL CONDITION FOR PROVIDING AN OUTPUT SIGNAL CORRESPONDING TO SAID RECORDED FREQUENCY MODULATED SIGNAL IN DEMODULATED FORM.
References Cited (Backward Citations)
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Cited
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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) | 1968-11-15 | 1969-05-17 | 1969-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-15 | 1973-05-17 | 1973-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-15 | 1977-05-17 | 1977-11-16 | $7700.00 | Window Closed / Lapsed |