System for recording and reproducing a wide-band signal

Claim 1

A system for recording and reproducing a wide-band signal on a recording medium having the capability of recording only about half of said wide-band, said system comprising means for recording a signal comprising a high frequency band component divided out of said wide-band and a frequency modulated carrier wave which is modulated responsive to a lower frequency band component remaining after said high frequency component is divided out, reproducing means for reproducing the signal recorded by said recording means, means for separating said high frequency band component and said frequency modulated carrier wave in the reproduced signal, a high frequency circuit means for carrying the high frequencies and a frequency modulated circuit means for carrying the frequency modulated signal, gain control means for controlling a level of the separated high frequency band component, detection means for detecting unwanted level vAriations of the frequency modulated component of the reproduced signal and producing its detection output, and means for obtaining the original wide-band signal from said high frequency band component and said frequency modulated carrier wave, said gain control means in the high frequency circuit means being controlled by said detection output of said detection means in the frequency modulated circuit means.

Claim 2

A system for recording and reproducing a wide-band signal on a recording medium having the capability of recording only about half of said wide-band, said system comprising means for recording a signal comprising a high frequency band component divided out of said wide-band and a frequency modulated carrier wave which is modulated responsive to a lower frequency band component remaining after said high frequency component is divided out, reproducing means for reproducing the signal recorded by said recording means, means for separating said high frequency band component and said frequency modulated carrier wave in the reproduced signal, a high frequency circuit means for carrying the high frequencies and a frequency modulated circuit means for carrying the frequency modulated signal, gain control means for controlling a level of the separated high frequency band component, detection means for detecting unwanted level vAriations of the frequency modulated component of the reproduced signal and producing its detection output, and means for obtaining the original wide-band signal from said high frequency band component and said frequency modulated carrier wave, said gain control means in the high frequency circuit means being controlled by said detection output of said detection means in the frequency modulated circuit means.

Claim 3

A system for recording and reproducing a wide-band signal on a magnetic medium, said system comprising means for dividing said wide-band signal into a low frequency band component and a high frequency band component, modulator means responsive to the low frequency band component for frequency modulating a carrier wave, said carrier wave being frequency modulated with an index of modulation which is over unity, the lower frequency limit of the deviated carrier wave being substantially equal to or higher than said high frequency band component, means for adjusting the signal levels of the high frequency band component and the frequency modulated carrier wave so that the carrier wave has a biasing effect with respect to the high frequency band component, means for thereafter mixing the high frequency band component and the frequency modulated carrier wave, means for magnetically recording the signal produced by said mixing means on said magnetic medium, means for reproducing said recorded mixed signal from said magnetic medium, means for separating the high frequency band component and the frequency modulated carrier wave from said reproduced signal, detector means for detecting unwanted level variations out of said frequency modulated carrier wave and for producing a detection output in response thereto, means for limiting the amplitude of said frequency modulated carrier wave before being demodulated, means for demodulating the frequency modulated carrier wave after it is separated from said reproduced mixed signal, means for adjusting the levels of the high frequency band component and the demodulated signal in such a manner that said levels agree with the original signal levels of said high frequency band component and said low frequency band component, said adjusting means controlling the levels of the high frequency band component in response to said detection output of said detector means, and means for mixing the high frequency band component and the demodulated signal after their levels are adjusted.

Claim 4

A system for recording and reproducing a wide-band signal on a magnetic medium, said system comprising means for dividing said wide-band signal into a low frequency band component and a high frequency band component, modulator means responsive to the low frequency band component for frequency modulating a carrier wave, said carrier wave being frequency modulated with an index of modulation which is over unity, the lower frequency limit of the deviated carrier wave being substantially equal to or higher than said high frequency band component, means for adjusting the signal levels of the high frequency band component and the frequency modulated carrier wave so that the carrier wave has a biasing effect with respect to the high frequency band component, means for thereafter mixing the high frequency band component and the frequency modulated carrier wave, means for magnetically recording the signal produced by said mixing means on said magnetic medium, means for reproducing said recorded mixed signal from said magnetic medium, means for separating the high frequency band component and the frequency modulated carrier wave from said reproduced signal, detector means for detecting unwanted level variations out of said frequency modulated carrier wave and for producing a detection output in response thereto, means for limiting the amplitude of said frequency modulated carrier wave before being demodulated, means for demodulating the frequency modulated carrier wave after it is separated from said reproduced mixed signal, means for adjusting the levels of the high frequency band component and the demodulated signal in such a manner that said levels agree with the original signal levels of said high frequency band component and said low frequency band component, said adjusting means controlling the levels of the high frequency band component in response to said detection output of said detector means, and means for mixing the high frequency band component and the demodulated signal after their levels are adjusted.

Claim 5

A method of recording and reproducing a very wide-band of video signals comprising the steps of: a. dividing the wide-band of signals into two narrow bands of signals; b. frequency modulating one of said narrow bands with said modulating being carried out at an index of modulation which exceeds unity; c. mixing said modulated and non-modulated narrow band of signals; d. recording said mixed signals on a recording medium; e. reproducing said recorded mixed signals from said recording medium; f. separating said reproduced signals into the modulated and non-modulated narrow band of signals; g. detecting level variations in the modulated one of the signal bands reproduced during the step (f) and producing a detection output responsive thereto; h. controlling the level of the other of said signal bands responsive to said detection output; and i. mixing said reproduced signals and obtaining the original wide-band of signals.

Claim 6

A method of recording and reproducing a very wide-band of video signals comprising the steps of: a. dividing the wide-band of signals into two narrow bands of signals; b. frequency modulating one of said narrow bands with said modulating being carried out at an index of modulation which exceeds unity; c. mixing said modulated and non-modulated narrow band of signals; d. recording said mixed signals on a recording medium; e. reproducing said recorded mixed signals from said recording medium; f. separating said reproduced signals into the modulated and non-modulated narrow band of signals; g. detecting level variations in the modulated one of the signal bands reproduced during the step (f) and producing a detection output responsive thereto; h. controlling the level of the other of said signal bands responsive to said detection output; and i. mixing said reproduced signals and obtaining the original wide-band of signals.

Claim 7

A system for recording and reproducing a wide-band signal on a magnetic medium, said system comprising means for dividing said wide-band signal into low and high frequency bands, a source of a carrier frequency, means responsive to said low frequency band for frequency modulating said carrier with a modulation index greater than unity, the lower limit of modulation deviations being equal to or higher than the upper limit of said high frequency band, means for synchronizing and mixing the high frequency band and modulated carrier, means for magnetically recording the mixed signal on said magnEtic medium, means for reproducing said mixed signals from said magnetic medium, means for separating the high frequency band and frequency modulated carrier, means for detecting unwanted level variations in said frequency modulated carrier, means for limiting the amplitude of said frequency modulated carrier, means for demodulating said frequency modulated carrier, means responsive to said detector means for adjusting the level of the high frequency band, and means for mixing the adjusted high frequency band and demodulated frequencies.

Claim 8

A system for recording and reproducing a wide-band signal on a magnetic medium, said system comprising means for dividing said wide-band signal into low and high frequency bands, a source of a carrier frequency, means responsive to said low frequency band for frequency modulating said carrier with a modulation index greater than unity, the lower limit of modulation deviations being equal to or higher than the upper limit of said high frequency band, means for synchronizing and mixing the high frequency band and modulated carrier, means for magnetically recording the mixed signal on said magnEtic medium, means for reproducing said mixed signals from said magnetic medium, means for separating the high frequency band and frequency modulated carrier, means for detecting unwanted level variations in said frequency modulated carrier, means for limiting the amplitude of said frequency modulated carrier, means for demodulating said frequency modulated carrier, means responsive to said detector means for adjusting the level of the high frequency band, and means for mixing the adjusted high frequency band and demodulated frequencies.

Claim 9

A system for recording and reproducing a wide-band signal on a magnetic medium, said system comprising means for dividing said wide-band signal into low and high frequency bands, a source of a carrier frequency, means responsive to said low frequency band for frequency modulating said carrier with a modulation index greater than unity, means for synchronizing and mixing the high frequency band and modulated carrier, means for magnetically recording the mixed signal on said magnetic medium, means for reproducing said mixed signals from said magnetic medium, means for separating the high frequency band and frequency modulated carrier means for detecting unwanted level variations in said frequency modulated carrier, means for limiting the amplitude of said frequency modulated carrier, means for demodulating said frequency modulated carrier, means responsive to said detector means for adjusting the level of the high frequency band, and means for mixing the adjusted high frequency band and demodulated frequencies.

Claim 10

A system for recording and reproducing a wide-band signal on a magnetic medium, said system comprising means for dividing said wide-band signal into low and high frequency bands, a source of a carrier frequency, means responsive to said low frequency band for frequency modulating said carrier with a modulation index greater than unity, means for synchronizing and mixing the high frequency band and modulated carrier, means for magnetically recording the mixed signal on said magnetic medium, means for reproducing said mixed signals from said magnetic medium, means for separating the high frequency band and frequency modulated carrier means for detecting unwanted level variations in said frequency modulated carrier, means for limiting the amplitude of said frequency modulated carrier, means for demodulating said frequency modulated carrier, means responsive to said detector means for adjusting the level of the high frequency band, and means for mixing the adjusted high frequency band and demodulated frequencies.

Claim 11

A system for recording and reproducing a wide-band of video signals on a recording medium, said system comprising means for dividing said wide-band signals into a low frequency band component and a high frequency band component, frequency modulator means having an index of modulation which is greater than unity for frequency modulating a carrier wave responsive to said low frequency band component, the lower frequency limit of the deviated carrier wave being substantially equal to or higher than the highest frequency of said high frequency band component of said wide-band signal, means responsive to the high frequency component and the frequency modulated carrier wave produced by said modulator means for simultaneously recording a mixture of said high frequency component and the frequency modulated carrier wave on said recording medium at a level at which the frequency modulated carrier wave has a biasing effect with respect to the high frequency band component, means for reproducing from the recording medium the mixed high frequency component and the frequency modulated carrier wave, means for dividing the high frequency component from the frequency modulated carrier wave, and level fixing means responsive to the amplitude variations of said reproduced frequency modulated carrier wave for controlling the amplitude level of the reproduced high frequency band component.

Claim 12

A system for recording and reproducing a wide-band of video signals on a recording medium, said system comprising means for dividing said wide-band signals into a low frequency band component and a high frequency band component, frequency modulator means having an index of modulation which is greater than unity for frequency modulating a carrier wave responsive to said low frequency band component, the lower frequency limit of the deviated carrier wave being substantially equal to or higher than the highest frequency of said high frequency band component of said wide-band signal, means responsive to the high frequency component and the frequency modulated carrier wave produced by said modulator means for simultaneously recording a mixture of said high frequency component and the frequency modulated carrier wave on said recording medium at a level at which the frequency modulated carrier wave has a biasing effect with respect to the high frequency band component, means for reproducing from the recording medium the mixed high frequency component and the frequency modulated carrier wave, means for dividing the high frequency component from the frequency modulated carrier wave, and level fixing means responsive to the amplitude variations of said reproduced frequency modulated carrier wave for controlling the amplitude level of the reproduced high frequency band component.

Claim 15

A system for recording and reproducing a video signal, said system comprising: a. means for dividing said video signal into a low frequency band component below a predetermined dividing frequency and a high frequency band component above the predetermined divIding frequency, said predetermined dividing frequency being a frequency higher than the order of 0.1 MHz; b. frequency modulator means having a modulation index which is greater than unity for frequency modulating a carrier wave responsive to said low frequency band component, the frequency of said carrier wave and the value of said modulation index being selected so that the lower frequency limit of the deviated carrier wave is substantially equal to or higher than the highest frequency of said high frequency band component and a total frequency band width of high frequency band component and the frequency modulated low frequency band component is less than the orders of four octaves; c. means for controlling the levels of the high frequency band component and the frequency modulated low frequency band component so that the frequency modulated low frequency band component has a biasing effect with respect to the high frequency band component; d. means for mixing the high frequency band component and the frequency modulated low frequency band component respectively having the controlled level; e. means for recording the mixed high frequency band component and frequency modulated low frequency band component on a recording medium with a biasing effect of the frequency modulated low frequency band component; f. means for reproducing the recorded high frequency band component and frequency modulated low frequency band component; g. means for separating the reproduced high frequency band component and the frequency modulated low frequency band component; h. detection means for detecting unwanted level variations out of the frequency modulated low frequency band component of the reproduced signal and producing its detection output; i. means for limiting the amplitude of the separated frequency modulated low frequency band component; j. means for demodulating the separated frequency modulated low frequency band component; k. gain control means for controlling a level of the separated high frequency band component, said gain control means being controlled by said detection output of said detection means; l. means for delaying the high frequency band component with respect to the low frequency band component; and m. means for mixing the separated high frequency band component and the demodulated low frequency band component and obtaining a reproduced video signal.

Claim 16

A system for recording and reproducing a video signal, said system comprising: a. means for dividing said video signal into a low frequency band component below a predetermined dividing frequency and a high frequency band component above the predetermined divIding frequency, said predetermined dividing frequency being a frequency higher than the order of 0.1 MHz; b. frequency modulator means having a modulation index which is greater than unity for frequency modulating a carrier wave responsive to said low frequency band component, the frequency of said carrier wave and the value of said modulation index being selected so that the lower frequency limit of the deviated carrier wave is substantially equal to or higher than the highest frequency of said high frequency band component and a total frequency band width of high frequency band component and the frequency modulated low frequency band component is less than the orders of four octaves; c. means for controlling the levels of the high frequency band component and the frequency modulated low frequency band component so that the frequency modulated low frequency band component has a biasing effect with respect to the high frequency band component; d. means for mixing the high frequency band component and the frequency modulated low frequency band component respectively having the controlled level; e. means for recording the mixed high frequency band component and frequency modulated low frequency band component on a recording medium with a biasing effect of the frequency modulated low frequency band component; f. means for reproducing the recorded high frequency band component and frequency modulated low frequency band component; g. means for separating the reproduced high frequency band component and the frequency modulated low frequency band component; h. detection means for detecting unwanted level variations out of the frequency modulated low frequency band component of the reproduced signal and producing its detection output; i. means for limiting the amplitude of the separated frequency modulated low frequency band component; j. means for demodulating the separated frequency modulated low frequency band component; k. gain control means for controlling a level of the separated high frequency band component, said gain control means being controlled by said detection output of said detection means; l. means for delaying the high frequency band component with respect to the low frequency band component; and m. means for mixing the separated high frequency band component and the demodulated low frequency band component and obtaining a reproduced video signal.