US3681522A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for minimizing fluctuations of television signal
Assignee: Panasonic Holdings Corp
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Filing: 1970-06-05
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Granted: 1972-08-01
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Expires: 1990-06-05
Abstract
Abstract An arrangement for minimizing the picture quality reducing fluctuations in television signals reproduced from a video tape recorder and supplied to a television receiver. Television signals reproduced from the video tape recorder are applied to signal switching means and signal separator means, respectively. The signal switching means remove only horizontal synchronizing pulses from the reproduced television signals and result in modified picture signals. The signal separator means take out horizontal synchronizing pulses selectively, which are applied to a time base processor means in which the timing of the horizontal synchronizing pulses is modulated so as to compensate for the phase shift caused by the automatic frequency control circuit in a monitor television receiver. The modified picture signals and processed horizontal synchronizing pulses are added together by mixer means, and then are supplied to a monitor television receiver. As a result, the picture quality reducing fluctuations of the reproduced television signals are minimized.
Inventors
- 👤 Kenzo Tanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:59
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/76; H04N5/91; H04N5/93; H04N5/932; H04N5/78
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
188 words
A system for minimizing picture quality reducing fluctuations in television signals for reproduction on the screen of a monitor television receiver which fluctuations are caused by timing errors contained in the television signals including vertical and horizontal synchronizing signals, said system comprising switching means for removing only the horizontal synchronizing signals from said television signals so as to produce modified picture signals; separator means for selectively separating the horizontal synchronizing signals from said television signals; mixer means connected to said switching means; and time base processor means coupled between said separator means and said mixer means and which include timing error detector means and time base modulator means as fundamental elements, for processing the timing of said separated horizontal synchronizing signals by a timing error signal detected from said separated horizontal synchronizing signals so as to compensate for the timing error transfer function of the automatic frequency control circuit in said monitor television receiver, and said processed horizontal synchronizing signals being additively mixed with said modified picture signals by said mixer means so as to produce processed television signals which can be applied to said monitor television receiver.
Claim 2
Independent Claim
188 words
A system for minimizing picture quality reducing fluctuations in television signals for reproduction on the screen of a monitor television receiver which fluctuations are caused by timing errors contained in the television signals including vertical and horizontal synchronizing signals, said system comprising switching means for removing only the horizontal synchronizing signals from said television signals so as to produce modified picture signals; separator means for selectively separating the horizontal synchronizing signals from said television signals; mixer means connected to said switching means; and time base processor means coupled between said separator means and said mixer means and which include timing error detector means and time base modulator means as fundamental elements, for processing the timing of said separated horizontal synchronizing signals by a timing error signal detected from said separated horizontal synchronizing signals so as to compensate for the timing error transfer function of the automatic frequency control circuit in said monitor television receiver, and said processed horizontal synchronizing signals being additively mixed with said modified picture signals by said mixer means so as to produce processed television signals which can be applied to said monitor television receiver.
Claim 3
Dependent Claim
200 words
A system as claimed in claim 1 in which said time base processor means further comprises timing error eliminator means also coupled to said separator means for eliminating said timing error from said separated horizontal synchronizing signals so as to produce horizontal synchronizing signals having a uniform period; equalizer means coupled between timing erroR detector means and said time base modulator means for equalizing said detected timing error signal in a weighted relationship; and wave shaping and delaying means coupled to said time base modulator means for shaping the waveform of said modulated horizontal synchronizing signals in a conventional form and for delaying said modulated horizontal synchronizing signals so that their position accords with the horizontal blanking portion of said modified picture signals which are produced by said switching means, whereby the resulting processed horizontal synchronizing signals can be supplied to said mixer means; the weighted relationship according to which said equalizer means equalizes the detected timing error signal being such that when taken in conjunction with the operation of said timing error detector means and said time base modulator means said system compensates said timing error transfer function of the automatic frequency control circuit in said monitor television receiver.
Claim 4
Dependent Claim
212 words
A system as claimed in claim 1 in which said time timing error detecting means comprises an automatic frequency control circuit means for detecting said timing error signal from said separated horizontal synchronizing signals and having the same timing error transfer function as the automatic frequency control circuit in said monitor television receiver; and said time base processor further comprises equalizer means coupled between said automatic frequency control circuit and said time base modulator means for equalizing said detected timing error signal in a weighted relationship; and wave shaping and delaying means coupled to said time base modulator means for shaping the waveform of said modulated horizontal synchronizing signals in a conventional form and for delaying said modulated horizontal synchronizing signals so that their position accords with the horizontal blanking portion of said modified picture signals which are produced by said switching means, whereby the resulting processed horizontal synchronizing signals can be supplied to said mixer means; the weighted relationship according to which said equalizer means equalizes the detected timing error signal being such that when taken in conjunction with the operation of said automatic frequency control circuit means and said modulator means said system compensates said timing error transfer function of the automatic frequency control circuit in said monitor television receiver.
Claim 5
Dependent Claim
228 words
A system as claimed in claim 1 in which said timing error detecting means comprises automatic frequency control circuit means for detecting said timing error signal from said separated horizontal synchronizing signals and for producing stabilized horizontal synchronizing signals from said separated horizontal synchronizing signals and said circuit means having the same timing error transfer function as that of the automatic frequency control circuit in said monitor television receiver; and said time base processor further comprises equalizer means coupled between said automatic frequency control circuit and said time base modulator means for equalizing said detected timing error signal in a weighted relationship; and wave shaping and delaying means coupled to said time base modulator means for shaping the waveform of said modulated horizontal synchronizing signals in a conventional form and for delaying said modulated horizontal synchronizing signals so that their position accords with the horizontal blanking portion of said modified picture signals which are produced by said switching means, whereby the resulting processed horizontal synchronizing signals can be supplied to said mixer means; the weighted relationship according to which said equalizer means equalizes the detected timing error signal being such that when taken in conjunction with the operation of said automatic frequency control circuit means and said modulator means said system compensates said timing error transfer function of the automatic frequency control circuit in said monitor television receiver.
Claim 6
Dependent Claim
58 words
A system as claimed in claim 4 in which said automatic frequency control circuit means has two loops, one of which has the same open loop timing error transfer function as that of the automatic frequency control circuit in said monitor television receiver, and the other of which has an open loop timing error transfer function of unity.
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) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |