Abstract: A color video signal recording system comprises means for producing a quadrature two-phase balanced-modulated color signal by subjecting a subcarrier to quadrature two-phase balanced modulation by two color signals, means for producing a demodulation-purpose reference phase signal which has the same frequency as that of the subcarrier and which is to be frequency-interleaved with the quadrature two-phase balanced-modulated color signal, means for multiplexing the quadrature two-phase balanced-modulated color signal and the demodulation-purpose reference phase signal together with a luminance signal, and means for recording the multiplex signal on a recording medium after subjecting it to angle modulation.

Abstract: A color video signal recording system in which a quadrature two-phase balance-modulated color signal is produced by subjecting a subcarrier to quadrature two-phase balanced modulation by two color signals; and a demodulation-purpose reference phase signal is produced which has the same frequency as that of the subcarrier and which is to be frequency-interleaved with the quadrature two-phase balance-modulated color signal. The quadrature two-phase balance-modulated color signal and the demodulation-purpose reference phase signal together with a carrier luminance signal are multi-plexed and the multiplex signal recorded.

Abstract: The invention provides an apparatus for controlling the rotation of a rotating body in a recording and/or reproducing apparatus. First, the apparatus detects the rotational speed of the rotating body, as it is driven by a DC motor. Detection is in terms of a frequency which is n times the speed, in which n>> 1. Second, there is a detection of the rotational phase of the rotating body. The DC motor is driven to rotate in accordance with a controlling signal obtained by using first and second output error signals responsive to the first and second detections. The DC motor is driven by means for superimposing an AC signal generated with a constant period and the first and second output error signals. The superimposed signals are sliced at a predetermined level to perform "ON" - "OFF" operations and a smooth output to control the driving rotation of the DC motor.