Color video signal recording and reproducing system

Claim 1

A system for recording and reproducing a color video signal on a running recording medium comprising first filter means for separating a luminance signal from a color video signal, means for frequency modulating said luminance signal separated by said first filter means, second filter means for separating a carrier chrominance signal from said color video signal at each horizontal scanning period, first frequency converting means responsive to a reference signal for converting the separated frequency band of said carrier chromiNance signal to a frequency band which is lower than said frequency band of the carrier chrominance signal, means for superimposing the output of said frequency modulating means and the output of said frequency converting means one upon the other, means comprising a rotary magnetic head for recording said superimposed signal on and reproducing it from said running recording medium, third filter means for separating a frequency modulated luminance signal from a signal reproduced by said recording and reproducing means, means for demodulating said separated luminance signal, fourth filter means for separating the frequency converted carrier chrominance signal from said signal reproduced by said recording and reproducing means, second frequency converting means for frequency converting and restoring the frequency band of said carrier chrominance signal filtered by said fourth filter means to the original frequency band, means for obtaining a reproduced color video signal by mixing the output of said demodulating means and the output of said second frequency converting means, means for separating a color burst signal from the output signal of said second frequency converting means, oscillating means for producing a reference subcarrier frequency signal, means for comparing the phase of said color burst signal with the phase of the output signal of said oscillating means, voltage control oscillator means having a center frequency of oscillation which is controlled responsive to the output of said phase comparing means for supplying its output to said second frequency converting means, error detecting means operated responsive to the detection of an error in the running speed of said recording medium and for supplying the detected error output to said voltage control oscillator, means for forming a feedback loop including said second converting means, said color burst separating means, said phase comparing means, and said error detecting means, for controlling said voltage control oscillator, and means for preventing said feedback loop including said voltage control oscillator from being drawn to and locked at a false stabilizing point which is deviated from the frequency of the chrominance subcarrier by a frequency which is equal to a frequency of the horizontal synchronizing signal multiplied by an integer.

Claim 2

A system for recording and reproducing a color video signal on a running recording medium comprising first filter means for separating a luminance signal from a color video signal, means for frequency modulating said luminance signal separated by said first filter means, second filter means for separating a carrier chrominance signal from said color video signal at each horizontal scanning period, first frequency converting means responsive to a reference signal for converting the separated frequency band of said carrier chromiNance signal to a frequency band which is lower than said frequency band of the carrier chrominance signal, means for superimposing the output of said frequency modulating means and the output of said frequency converting means one upon the other, means comprising a rotary magnetic head for recording said superimposed signal on and reproducing it from said running recording medium, third filter means for separating a frequency modulated luminance signal from a signal reproduced by said recording and reproducing means, means for demodulating said separated luminance signal, fourth filter means for separating the frequency converted carrier chrominance signal from said signal reproduced by said recording and reproducing means, second frequency converting means for frequency converting and restoring the frequency band of said carrier chrominance signal filtered by said fourth filter means to the original frequency band, means for obtaining a reproduced color video signal by mixing the output of said demodulating means and the output of said second frequency converting means, means for separating a color burst signal from the output signal of said second frequency converting means, oscillating means for producing a reference subcarrier frequency signal, means for comparing the phase of said color burst signal with the phase of the output signal of said oscillating means, voltage control oscillator means having a center frequency of oscillation which is controlled responsive to the output of said phase comparing means for supplying its output to said second frequency converting means, error detecting means operated responsive to the detection of an error in the running speed of said recording medium and for supplying the detected error output to said voltage control oscillator, means for forming a feedback loop including said second converting means, said color burst separating means, said phase comparing means, and said error detecting means, for controlling said voltage control oscillator, and means for preventing said feedback loop including said voltage control oscillator from being drawn to and locked at a false stabilizing point which is deviated from the frequency of the chrominance subcarrier by a frequency which is equal to a frequency of the horizontal synchronizing signal multiplied by an integer.