US4639792A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for decoding video address code signals
Assignee: STYPHER CORP
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Filing: 1985-05-02
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Granted: 1987-01-27
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Expires: 2005-05-02
Abstract
Abstract Apparatus for decoding digitally-coded address signals embedded in video signals recorded on magnetic tape is disclosed. The apparatus can properly decode the address signals at both slow and fast tape speeds and utilizes a variable-frequency oscillator to generate timing signals for decoding the digitally-coded address. The address signals encoded on the magnetic tape normally include an error code which can be detected by conventional error checking circuitry and used to check whether the address signals have been correctly received. The oscillator frequency is adjusted in accordance with an error signal generated by the error checking circuitry until error-free detection of the address signals is achieved.
Inventors
- 👤 Edwin C. Moxon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:05
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/18; G11B20/1806; G11B20/1813; G11B27/00; G11B27/10; G11B27/19; G11B27/28; G11B27/30; G11B27/3027; G11B27/3036; G11B27/3054; G11B2220/00; G11B2220/90
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
95 words
In apparatus for reading coded information recorded on video magnetic tape, said apparatus having means for reading signals from said tape as said tape is run through said apparatus at different speeds, a local oscillator for generating sampling signals at various frequencies, means responsive to said sampling signals for sampling said signals read from said tape to produce received information, the improvement comprising, means responsive to the data content of selected portions of said received information read from said tape for adjusting the frequency of said sampling signals to produce error-free reception of said information.
Claim 2
Dependent Claim
95 words
In apparatus for reading coded information recorded on video magnetic tape, said apparatus having means for reading signals from said tape as said tape is run through said apparatus at different speeds, a local oscillator for generating sampling signals at various frequencies, means responsive to said sampling signals for sampling said signals read from said tape to produce received information, the improvement comprising, means responsive to the data content of selected portions of said received information read from said tape for adjusting the frequency of said sampling signals to produce error-free reception of said information.
Claim 3
Dependent Claim
82 words
In apparatus for reading coded information recorded on magnetic tape, the improvement according to claim 1 wherein said adjusting means comprises means for recording a coded data pattern on said tape in addition to data signals, means responsive to said sampling signals for reading data from said tape, said data including said coded pattern, means responsive to said coded data signal read from said tape for changing the frequency of said sampling signals to produce error-free reception of said coded data information.
Claim 4
Dependent Claim
64 words
In apparatus for reading coded information recorded on magnetic tape, the improvement according to claim 2 wherein said changing means comprises means responsive to said coded data signal read from said tape and to said original coded data signal for changing the frequency of said sampling signals until said coded data signal read from said tape and said original coded data signal are equal.
Claim 5
Dependent Claim
29 words
In apparatus for reading coded information recorded on magnetic tape, the improvement according to claim 2 wherein said recording means computes said coded data pattern from said data signals.
Claim 6
Dependent Claim
79 words
In apparatus for reading coded information recorded on magnetic tape, the improvement according to claim 4 wherein said changing means comprises means responsive to data read from said tape for recomputing said coded data signal and means responsive to said coded data signal read from said tape and to said recomputed coded data signal for changing the frequency of said sampling signals until said coded data signal read from said tape and said recomputed coded data signal are equal.
Claim 7
Dependent Claim
25 words
In apparatus for reading coded information recorded on magnetic tape, the improvement according to claim 2 wherein said coded data pattern is a predetermined pattern.
Claim 8
Dependent Claim
31 words
In apparatus for reading coded information recorded on magnetic tape, the improvement according to claim 6 wherein said coded data pattern is computed from said data signals by a predetermined formula.
References Cited (Backward Citations)
US3999129A
Cited
US4215335A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-01-26 | 1990-07-28 | 1991-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-26 | 1994-07-28 | 1995-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-26 | 1998-07-28 | 1999-01-27 | $7700.00 | Window Closed / Lapsed |