US3629491A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal-correcting apparatus
Assignee: Bell and Howell Co
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Filing: 1969-11-03
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Granted: 1971-12-21
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Expires: 1989-11-03
Abstract
Abstract Apparatus for providing a reference signal varying in phase in accordance with angular errors in a color video signal accompanied by a horizontal synchronization signal and by a color reference burst including a number of undesired sideband components stemming from a keying of the color reference burst at horizontal synchronization rate. The apparatus comprises a controlled oscillator for providing an output signal and for varying the phase of such output signal. The apparatus further includes a control loop for limiting frequency variations of this output signal to a range located between upper sideband components and lower sideband components of the number of undesired sideband components of the color reference burst, and a further control loop for causing the defined controlled oscillator to vary the phase of the above-mentioned output signal within the defined range in accordance with said angular errors, whereby such output signal provides the initially mentioned reference signal.
Inventors
- 👤 Bert H Dann
- 👤 Floyd M Gardner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:11
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/79; H04N9/87; H04N9/898
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
151 words
Apparatus for providing a reference signal varying in phase in accordance with angular errors in a color video signal accompanied by a color reference burst and a horizontal synchronization signal, said color reference burst including a number of sideband components stemming from a keying of said color reference burst at horizontal synchronization rate, comprising in combination: a. first means for providing an output signal and for varying the phase of said output signal; b. second means connected to said first means for limiting frequency variations of said output signal to a range located between upper sideband components and lower sideband components of said number of sideband components of the color reference burst; and c. third means connected to said first means for causing said first means to vary the phase of said output signal within said range in accordance with said angular errors, whereby said output signal provides said reference signal.
Claim 2
Dependent Claim
151 words
Apparatus for providing a reference signal varying in phase in accordance with angular errors in a color video signal accompanied by a color reference burst and a horizontal synchronization signal, said color reference burst including a number of sideband components stemming from a keying of said color reference burst at horizontal synchronization rate, comprising in combination: a. first means for providing an output signal and for varying the phase of said output signal; b. second means connected to said first means for limiting frequency variations of said output signal to a range located between upper sideband components and lower sideband components of said number of sideband components of the color reference burst; and c. third means connected to said first means for causing said first means to vary the phase of said output signal within said range in accordance with said angular errors, whereby said output signal provides said reference signal.
Claim 3
Dependent Claim
22 words
Apparatus as claimed in claim 1, wherein said first means and said second means are interconnected to provide frequency control loop means.
Claim 4
Dependent Claim
67 words
Apparatus as claimed in claim 2, wherein said second means in said frequency control loop means include: a. means for detecting frequency differences between said output signal and a signal derived from said horizontal synchronization signal; and b. means connected to said detecting means and to said first means for limiting frequency variations of said output signal to said range in response to said detected frequency differences.
Claim 5
Dependent Claim
13 words
Apparatus as claimed in claim 3, wherein said detecting means include quadricorrelator means.
Claim 6
Dependent Claim
189 words
Apparatus for providing a reference signal varying in phase in accordance with angular errors in a color video signal accompanied by a color reference burst and a horizontal synchronization signal, said coLor reference burst including a number of sideband components stemming from a keying of said color reference burst at horizontal synchronization rate, comprising in combination: a. first means for providing an output signal and for varying the phase of said output signal; b. second means for deriving from said horizontal synchronization signal a signal indicative of the horizontal synchronization rate; c. frequency control loop means including said first means and being connected to said second means for limiting, in response to said output signal and said horizontal synchronization rate signal, frequency variations of said output signal to a range located between upper sideband components and lower sideband components of said number of sideband components of the color reference burst; and d. phase-lock loop means including said first means for causing said first means to vary the phase of said output signal within said range in accordance with said angular errors, whereby said output signal provides said reference signal.
Claim 7
Dependent Claim
189 words
Apparatus for providing a reference signal varying in phase in accordance with angular errors in a color video signal accompanied by a color reference burst and a horizontal synchronization signal, said coLor reference burst including a number of sideband components stemming from a keying of said color reference burst at horizontal synchronization rate, comprising in combination: a. first means for providing an output signal and for varying the phase of said output signal; b. second means for deriving from said horizontal synchronization signal a signal indicative of the horizontal synchronization rate; c. frequency control loop means including said first means and being connected to said second means for limiting, in response to said output signal and said horizontal synchronization rate signal, frequency variations of said output signal to a range located between upper sideband components and lower sideband components of said number of sideband components of the color reference burst; and d. phase-lock loop means including said first means for causing said first means to vary the phase of said output signal within said range in accordance with said angular errors, whereby said output signal provides said reference signal.
Claim 8
Dependent Claim
57 words
Apparatus as claimed in claim 5, wherein said frequency control loop means include means for detecting frequency differences between said output signal and said horizontal synchronization rate signal and means connected between said detecting means and said first means for limiting frequency variations of said output signal to said range in response to said detected frequency differences.
Claim 9
Dependent Claim
13 words
Apparatus as claimed in claim 6, wherein said detecting means include quadricorrelator means.
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) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |