US3764734A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic peak color control
Assignee: GTE Sylvania Inc
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Filing: 1972-06-07
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Granted: 1973-10-09
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Expires: 1992-06-07
Abstract
Abstract The color level of a chroma signal in a color television receiver is automatically maintained by applying a chroma signal to a variable gain amplifier and utilizing a detector for applying the output signal back to the variable gain amplifier to vary the gain inversely with the peak level of the applied chroma signal and provide a substantially constant level of peak chroma signal independent of the percentage of chroma in the signal.
Inventors
- 👤 G Srivastava
- 👤 J Thomas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:13
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/68
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
89 words
In a color television receiver, color control circuitry comprising: a color signal source; variable gain amplifier means having color signal input and output circuits with said signal input circuit coupled to said color signal source; and detector means including a threshold detector means coupling said color signal output circuit to said variable gain amplifier means and an average detector means coupling said color signal input circuit to said threshold detector means whereby a control signal representative of a peak color signal is applied to said variable gain amplifier means.
Claim 2
Dependent Claim
89 words
In a color television receiver, color control circuitry comprising: a color signal source; variable gain amplifier means having color signal input and output circuits with said signal input circuit coupled to said color signal source; and detector means including a threshold detector means coupling said color signal output circuit to said variable gain amplifier means and an average detector means coupling said color signal input circuit to said threshold detector means whereby a control signal representative of a peak color signal is applied to said variable gain amplifier means.
Claim 3
Dependent Claim
32 words
The color control circuitry of claim 1 wherein said average detector means includes an alterable impedance coupled intermediate thereto and said threshold detector means for selecting a desired peak color signal level.
Claim 4
Dependent Claim
19 words
The color control circuitry of claim 2 wherein said alterable impedance is in the form of an adjustable resistor.
Claim 5
Dependent Claim
32 words
The color control circuitry of claim 1 wherein said detector means provides an output signal proportional to said peak color signal and independent of the percentage of chroma in a color signal.
Claim 6
Dependent Claim
20 words
The color control circuitry of claim 1 wherein said detector means has a noise bandwidth less than about 60 Hz.
Claim 7
Dependent Claim
121 words
A color control circuit for a color television receiver comprising: a color signal source; a color signal demodulation means; variable gain amplifier means having an input circuit coupled to said color signal source and an output circuit coupled to said demodulation means; and detector means in the form of a combined threshold detector coupling said output circuit to said variable gain amplifier means and an average detector coupling said input circuit to said threshold detector to modify the threshold, whereby the gain of said variable amplifier means varies in accordance with variations in the peak color signal applied to said input circuit to provide a substantially constant peak color signal level independent of the percentage of chroma of said output circuit.
Claim 8
Dependent Claim
121 words
A color control circuit for a color television receiver comprising: a color signal source; a color signal demodulation means; variable gain amplifier means having an input circuit coupled to said color signal source and an output circuit coupled to said demodulation means; and detector means in the form of a combined threshold detector coupling said output circuit to said variable gain amplifier means and an average detector coupling said input circuit to said threshold detector to modify the threshold, whereby the gain of said variable amplifier means varies in accordance with variations in the peak color signal applied to said input circuit to provide a substantially constant peak color signal level independent of the percentage of chroma of said output circuit.
Claim 9
Dependent Claim
24 words
The color control circuit of claim 6 wherein said detector means includes an alterable impedance for selecting a desired peak level of color signal.
Claim 10
Dependent Claim
39 words
The color control circuit of claim 7 wherein said alterable impedance is in the form of an adjustable resistor whereby a selected peak level of color signal is provided at said output circuit of said variable gain amplifier means.
References Cited (Backward Citations)
US3141064A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-08 | 1977-04-09 | 1977-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-08 | 1981-04-09 | 1981-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-08 | 1985-04-09 | 1985-10-09 | $7700.00 | Window Closed / Lapsed |