Chroma signal recording and reproducing circuit

A chroma signal reproducing circuit of a magnetic recording and reproducing apparatus for frequency-multiplexing at least a frequency-modulated luminance signal of a color video signal and a low-frequency converted chroma signal for recording on a magnetic recording medium and reproducing a color video signal therefrom, comprising:

• an ACC circuit;
• a frequency converter connected in series with said ACC circuit for frequency-converting the low-frequency converted chroma signal to a chroma signal;
• a comb filter connected to the series connection of said ACC circuit and said frequency converter for filtering the chroma signal;
• and
• a dynamic deemphasis circuit connected to an output of said comb filter for dynamically deemphasizing an output of said comb filter.

A chroma signal recording and reproducing circuit in a magnetic recording and reproducing apparatus for frequency-modulating a luminance signal of a color video signal, low-frequency converting a chroma signal of said color video signal, frequency-multiplexing at least the frequency-modulated luminance signal and the low-frequency converted chroma signal, recording the frequency-multiplexed luminance and chroma signals by a recording magnetic head on a magnetic recording medium and reproducing the frequency-multiplexed luminance and chroma signals by a reproducing magnetic head from said magnetic recording medium, said chroma signal recording and reproducing circuit comprising:

• chroma signal recording means coupled for connection to said recording magnetic head including at least a first ACC circuit and a first frequency converter connected in series with said first ACC circuit for low-frequency converting the chroma signal;
• and
• chroma signal reproducing means coupled for connection to said reproducing magnetic head including said first ACC circuit and a second frequency converter connected in series wih said first ACC circuit for frequency-converting the low-frequency converted chroma signal, a first comb filter connected to an output of the series connection of said first ACC circuit and second frequency converter, and a dynamic deemphasis circuit connected to an output of said first comb filter, wherein said chroma signal recording means further includes a dynamic emphasis circuit connected to an output of said first ACC circuit for dynamically emphasizing an output signal of said first ACC circuit in response to said output signal of said first ACC circuit, wherein said first frequency converter is connected to an output of said dynamic emphasis circuit, wherein said first ACC circuit includes a variable gain amplifier and a detector for producing a control signal to said amplifier, and wherein said recording and reproducing circuit further comprises a first switch for selectively connecting an input terminal of said detector to an input stage of said emphasis circuit or an output stage of said deemphasis circuit.