Apparatus for recording a video signal sampled at frequency fs and reproducing the video signal as a signal essentially sampled at frequency 2fs

Claim 1

An apparatus for recording and reproducing a video signal on and from a recording medium, said video signal being accompanied by synchronizing signals but not by other multiplexed signals, said apparatus comprising: a sampling pulse generator supplied with a video signal, for producing sampling signals φ 1 and φ 2 which are in phase with a horizontal synchronizing signal of the video signal and mutually differ in phase by 180°, each of said sampling signals φ 1 and φ 2 having a frequency f s which satisfies an equation f.sub.s =(2n+1)f.sub.H /2, where n is and integer anf f H is a horizontal scanning frequency of the video signal; first sampling means for sampling a recording video signal which is to be recorded by the sampling signal φ 1 which is produced by said sampling pulse generator when said sampling pulse generator is supplied with said recording video signal, said recording video signal having a band with an upper limit frequency f a , said frequencies f a and f s satisfying a relation f a <f s <2f a ; recording and reproducing means for recording an output signal of said first sampling means on the recording medium and for reproducing the signal from the recording medium; delay means for delaying a reproduced video signal which is reproduced from the recording medium by said recording and reproducing means by a delay time of one horizontal scanning period; second sampling means for alternately sampling input and output signals of said delay means by the sampling signals φ 1 and φ 2 which are produced by said sampling pulse generator when said sampling pulse generator is supplied with said reproduced video signal, said second sampling means comprising a first sampler for sampling the input signal of said delay means by the sampling signal φ 1 , and a second sampler for sampling the output signal of said delay means by the sampling signal φ 2 ; and adding means for adding alternately sampled signals from said second sampling means, and for obtaining a reproduced output signal which has essentially been sampled at a frequency of 2f s .

Claim 2

An apparatus for recording and reproducing a video signal on and from a recording medium, said video signal being accompanied by synchronizing signals but not by other multiplexed signals, said apparatus comprising: a sampling pulse generator supplied with a video signal, for producing sampling signals φ 1 and φ 2 which are in phase with a horizontal synchronizing signal of the video signal and mutually differ in phase by 180°, each of said sampling signals φ 1 and φ 2 having a frequency f s which satisfies an equation f.sub.s =(2n+1)f.sub.H /2, where n is and integer anf f H is a horizontal scanning frequency of the video signal; first sampling means for sampling a recording video signal which is to be recorded by the sampling signal φ 1 which is produced by said sampling pulse generator when said sampling pulse generator is supplied with said recording video signal, said recording video signal having a band with an upper limit frequency f a , said frequencies f a and f s satisfying a relation f a <f s <2f a ; recording and reproducing means for recording an output signal of said first sampling means on the recording medium and for reproducing the signal from the recording medium; delay means for delaying a reproduced video signal which is reproduced from the recording medium by said recording and reproducing means by a delay time of one horizontal scanning period; second sampling means for alternately sampling input and output signals of said delay means by the sampling signals φ 1 and φ 2 which are produced by said sampling pulse generator when said sampling pulse generator is supplied with said reproduced video signal, said second sampling means comprising a first sampler for sampling the input signal of said delay means by the sampling signal φ 1 , and a second sampler for sampling the output signal of said delay means by the sampling signal φ 2 ; and adding means for adding alternately sampled signals from said second sampling means, and for obtaining a reproduced output signal which has essentially been sampled at a frequency of 2f s .