Patent US4380779A successfully refreshed from Google Patents.
US4380779A
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US
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Method for recording multiplexed signals on metal evaporated tape
Assignee: Panasonic Holdings Corp
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Filing: 1981-03-23
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Granted: 1983-04-19
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Expires: 2001-03-23
Abstract
Abstract A magnetic recording method for recording a multiplex signal having two different frequency signals. A magnetic recording medium is used having a magnetic layer with a thickness which is smaller than a recorded wavelength of each of said two signals. The signal of a higher frequency is recorded at a current which is more than 2dB larger than the lower limit of the recording current with which a reproduced output level is saturated, and which is smaller than a current with which the reproduced output level is reduced by 1dB beyond said saturated condition. The signal of a lower frequency is recorded at a current which is smaller than one half of that of the signal of a higher frequency.
Inventors
- 👤 Sadafumi Kitamura
- 👤 Hiroshi Taniguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:41
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/02; G11B5/74; G11B5/82; H; H04; H04N; H04N5/00; H04N5/76; H04N5/91; H04N5/92; H04N5/9201; H04N5/9202; H04N5/9204; H04N9/00; H04N9/79; H04N9/80; H04N9/82; H04N9/83
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
135 words
A magnetic recording method for recording a multiplex signal comprising two principal signals, comprising the steps of: using a magnetic recording medium having a magnetic layer with the thickness which is smaller than a recorded wavelength of each of said two principal signals; recording one of said principal signals having a higher frequency than that of the other signal at a current which is more than 2 dB greater than the lower limit of the recording current with which a reproduced output level is saturated, and which is smaller than a current with which the reproduced output level is reduced by 1 dB beyond said saturated condition; and recording said other principal signal of a lower frequency at a current which is smaller than one half of that of said signal of a higher frequency.
Claim 2
Dependent Claim
135 words
A magnetic recording method for recording a multiplex signal comprising two principal signals, comprising the steps of: using a magnetic recording medium having a magnetic layer with the thickness which is smaller than a recorded wavelength of each of said two principal signals; recording one of said principal signals having a higher frequency than that of the other signal at a current which is more than 2 dB greater than the lower limit of the recording current with which a reproduced output level is saturated, and which is smaller than a current with which the reproduced output level is reduced by 1 dB beyond said saturated condition; and recording said other principal signal of a lower frequency at a current which is smaller than one half of that of said signal of a higher frequency.
Claim 3
Dependent Claim
33 words
A magnetic recording method as claimed in claim 1, in which said multiplex signal comprises a frequency modulated luminance signal and a frequency converted chrominance signal in a color video signal recording system.
Claim 4
Dependent Claim
46 words
A magnetic recording method as claimed in claim 1, in which one or more additional signals other than said two principal signals are recorded in a multiplexed condition at a magnitude which is small enough not to substantially affect the transducing of said two principal signals.
Claim 5
Dependent Claim
41 words
A magnetic recording method as claimed in claim 1, in which said signal of a higher frequency is recorded at a current which is smaller than the upper limit of the recording current with which the reproduced output level is saturated.
Claim 6
Dependent Claim
36 words
A magnetic recording method as claimed in claim 1, in which said signal of a lower frequency is recorded at a current which is smaller than two-fifths of that of said signal of a higher frequency.
Claim 7
Dependent Claim
24 words
A magnetic recording method as claimed in claim 1, in which the magnetic layer of the magnetic recording medium comprises a vacuum-evaporated metal layer.
References Cited (Backward Citations)
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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) | 1986-04-18 | 1986-10-18 | 1987-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-18 | 1990-10-18 | 1991-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-18 | 1994-10-18 | 1995-04-19 | $7700.00 | Window Closed / Lapsed |