US3967317A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Predistortion of NRZ recording current for video recordings
Assignee: Westinghouse Electric Corp
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Filing: 1974-12-24
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Granted: 1976-06-29
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Expires: 1994-12-24
Abstract
Abstract Undesirable interference beat patterns in the displayed video signals produced by a magnetic record/reproduce head are substantially eliminated by appropriately changing the amplitude of the writing current to the head in synchronism with the polarity reversal to establish a current ratio which will result in uniform spacing between zero crossovers in the voltage output of the magnetic recording system.
Inventors
- 👤 George F. Newell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:28
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/02; G11B5/027; G11B5/035; H; H04; H04N; H04N5/00; H04N5/76; H04N5/91; H04N5/92
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
103 words
A method of minimizing harmonic distortion in the replayed output signals from a magnetic record/reproduction system wherein a remanent magnetic field exists in the magnetic recording medium as a result of erasure of the medium, comprising the steps of: supplying alternate half cycles of writing current to the recording head of said system, and adjusting the amplitude of said writing current in synchronism with the polarity reversal of the alternate half cycles of said writing current to establish a current ratio between alternate half cycles of said writing current to produce uniform spacing between the replayed output signals from said magnetic record/reproduction system.
Claim 2
Independent Claim
103 words
A method of minimizing harmonic distortion in the replayed output signals from a magnetic record/reproduction system wherein a remanent magnetic field exists in the magnetic recording medium as a result of erasure of the medium, comprising the steps of: supplying alternate half cycles of writing current to the recording head of said system, and adjusting the amplitude of said writing current in synchronism with the polarity reversal of the alternate half cycles of said writing current to establish a current ratio between alternate half cycles of said writing current to produce uniform spacing between the replayed output signals from said magnetic record/reproduction system.
Claim 3
Dependent Claim
104 words
Apparatus for minimizing harmonic distortion in replayed output signals from a magnetic record/reproduction system wherein a remanent magnetic field exists in the magnetic recording medium has a result of erasure of the medium, comprising, first means for supplying alternate half cycles of writing current to the recording head of said system, and second means for adjusting the amplitude of said writing current in synchronism with the polarity reversal of the alternate half cycles of said writing current to establish a current ratio between alternate half cycles of said writing current to produce uniform spacing between the replayed output signals from said magnetic record/reproduction system.
Claim 4
Dependent Claim
104 words
Apparatus for minimizing harmonic distortion in replayed output signals from a magnetic record/reproduction system wherein a remanent magnetic field exists in the magnetic recording medium has a result of erasure of the medium, comprising, first means for supplying alternate half cycles of writing current to the recording head of said system, and second means for adjusting the amplitude of said writing current in synchronism with the polarity reversal of the alternate half cycles of said writing current to establish a current ratio between alternate half cycles of said writing current to produce uniform spacing between the replayed output signals from said magnetic record/reproduction system.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-29 | 1979-12-29 | 1980-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-29 | 1983-12-29 | 1984-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-29 | 1987-12-29 | 1988-06-29 | $7700.00 | Window Closed / Lapsed |