Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
194 words
In apparatus for processing PAL-type encoded color television signals, the combination comprising: means for deriving from said encoded color television signals, during successive line intervals, subcarrier sideband components representative of a B-Y color difference signal to the substantial exclusion of accompanying subcarrier sideband components representative of an R-Y color-difference signal, and, during successive inter-line burst intervals, a constantphase B-Y synchronizing burst component to the substantial exclusion of an accompanying R-Y synchronizing burst component; synchronous demodulation means responsive to the output of said component deriving means and having an output terminal; a source of reference oscillations of subcarrier frequency and controllable phase; means coupled to said source of reference oscillations for supplying reference oscillations to said synchronous demodulation meaNs in a first phase during successive line intervals and in a second phase, in quadrature to said first phase, during successive inter-line burst intervals; means coupled to said source for cntrolling the phase of the reference oscillations provided by said source; and means, including signal gating means coupled to said output terminal, for rendering said phase controlling means responsive to that portion of the output of said synchronous demodulation means developed during said inter-line burst intervals.
Claim 2
Dependent Claim
194 words
In apparatus for processing PAL-type encoded color television signals, the combination comprising: means for deriving from said encoded color television signals, during successive line intervals, subcarrier sideband components representative of a B-Y color difference signal to the substantial exclusion of accompanying subcarrier sideband components representative of an R-Y color-difference signal, and, during successive inter-line burst intervals, a constantphase B-Y synchronizing burst component to the substantial exclusion of an accompanying R-Y synchronizing burst component; synchronous demodulation means responsive to the output of said component deriving means and having an output terminal; a source of reference oscillations of subcarrier frequency and controllable phase; means coupled to said source of reference oscillations for supplying reference oscillations to said synchronous demodulation meaNs in a first phase during successive line intervals and in a second phase, in quadrature to said first phase, during successive inter-line burst intervals; means coupled to said source for cntrolling the phase of the reference oscillations provided by said source; and means, including signal gating means coupled to said output terminal, for rendering said phase controlling means responsive to that portion of the output of said synchronous demodulation means developed during said inter-line burst intervals.
Claim 3
Dependent Claim
179 words
Apparatus in accordance with claim 1, also including: second means for deriving from said encoded color television signals, during said line intervals, subcarrier sideband components representative of an R-Y color-difference signal to the substantial exclusion of accompanying subcarrier sideband components representative of a B-Y color-difference signal, and, during said burst intervals, an R-Y burst synchronizing component, subject to phase reversal in successive burst intervals, to the substantial exclusion of an accompanying B-Y synchronizing component; second synchronous demodulation means responsive to the output of said second component deriving means and having a second output terminal; second means coupled to said source of reference oscillations for supplying reference oscillations to said second synchronous demodulation means; frequency selective amplifier means for supplying an input signal to said first and second component deriving means; means for controlling the gain of said frequency selective amplifier means; and means, including second signal gating means coupled to said second output terminal, for rendering said gain controlling means responsive to that portion of the output of said second synchronous demodulation means developed during said inter-line burst intervals.
Claim 4
Dependent Claim
51 words
Apparatus in accordance with claim 2, also including: means for alternatively enabling or disabling said frequency selective amplifier means; and means, including said second signal gating means, for rendering said enabling/disabling means responsive to that portion of the output of said second synchronous demodulation means developed during said inter-line burst intervals.
Claim 5
Dependent Claim
66 words
Apparatus in accordance with claim 2, also including a luminance signal path; means for optionally subjecting the signals in said luminance signal path to subcarrier frequency trapping; and means, including said second signal gating means coupled to said second signal output terminal, for rendering said trapping means responsive to that portion of the output of said second synchronous demodulation means developed during said inter-line burst intervals.
Claim 6
Dependent Claim
85 words
Apparatus in accordance with claim 2, wherein said second reference oscillation supplying means includes means for reversing the phase of the supplied reference oscillation in alternate line intervals, and wherein said apparatus also includes: means for controlling the mode of operation of said phase reversing means; and means, including said second signal gating means coupled to said second output terminal, for rendering said mode controlling means responsive to that portion of the output of said second synchronous demodulation means developed during said inter-line burst intervals.
Claim 7
Dependent Claim
199 words
Apparatus in accordance with claim 5, also including a source of line rate triggering pulses; and wherein said mode controlling means includes a bistable multivibrator, subject to triggering between first and second stable states in response to pulses from said line rate triggering pulse source, for developing switching waveforms, said reference oscillation phase reversing means being responsive to said switching waveforms; and wherein said means for rendering said mode controlling means responsive to an output of said second synchronous demodulation means includes: a source of line rate reset pulses; means for applying pulses from said reset pulse source to said bistable multiVibratpr; and means, coupled to the output of said second signal gating means and responsive to that portion of the output of said second synchronous demodulation means developed during said inter-line burst intervals, for disabling said reset pulse applying means when the output of said second signal gating means is indicative of the presence in the output of said second deriving means of an R-Y synchronizing burst component subject to phase reversal in successive burst intervals in a sense bearing a desired relationship to the sense of phase reversal of reference oscillations effected by said phase reversing means.
Claim 8
Dependent Claim
174 words
Apparatus in accordance with claim 6, also including: means, responsive to the output of said second signal gating means, for (1) enabling the operation of said frequency selective amplifier means when the output of said second signal gating means is indicative of the presence in the output of said second deriving means of an R-Y synchronizing burst component subject to phase reversal in successive burst intervals in a sense bearing said desired relationship to the sense of reference oscillation phase reversal, and (2) applying a disabling bias to said frequency selective amplifier means when the output of said second signal gating means fails to indicate such component presence; and means, coupled to said source of line rate reset pulses, for applying enabling pulses to said frequency selective amplifier means to overcome said disabling bias during said inter-line burst intervals, said enabling pulse applying means being responsive to the output of said second signal gating means and subject to actuation whenever the output of said second signal gating means fails to indicate such component presence.