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US3961367A
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Self-clocking, error correcting low bandwidth digital recording system
Assignee: RCA Corp
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Filing: 1974-07-03
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Granted: 1976-06-01
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Expires: 1994-07-03
Abstract
Abstract Circuit and method for electrically recording digital data by identifying the beginning of each cell boundary with a pulse and recording an intercell transition for one binary value and no transition for the other binary value.
Inventors
- 👤 Chin Tao Wu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:46
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1407; G11B20/1411
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
58 words
A method for recording digital data signals comprising the steps of: recording a pulse to identify the beginning of each cell time; recording one digital value by a single change in polarity of the recorded signal during the cell time; and recording another digital value by maintaining the same polarity of the recorded signal during the cell time.
Claim 2
Independent Claim
58 words
A method for recording digital data signals comprising the steps of: recording a pulse to identify the beginning of each cell time; recording one digital value by a single change in polarity of the recorded signal during the cell time; and recording another digital value by maintaining the same polarity of the recorded signal during the cell time.
Claim 3
Dependent Claim
20 words
The method claimed in claim 1 wherein width of said pulse is not greater than 25% of a cell time.
Claim 4
Dependent Claim
25 words
The method claimed in claim 2 wherein the digital value polarity change occurs within 75% of a cell time from the end of a pulse.
References Cited (Backward Citations)
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US3237176A
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US3281806A
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US3395355A
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US3737896A
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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) | 1979-06-01 | 1979-12-01 | 1980-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-01 | 1983-12-01 | 1984-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-01 | 1987-12-01 | 1988-06-01 | $7700.00 | Window Closed / Lapsed |