Secam recording and reproducing system

Claim 2

In apparatus for recording a SECAM composite color television signal in parallel tracks on a record medium by separating the luminance and chrominance components from said SECAM television signal, modulating said luminance component to a higher frequency range, converting said chrominance component to a lower frequency range, and recording the modulated luminance component and frequency-converted chrominance component, the improvement comprising means for generating first and second frequency-converting carrier signals; phase control means for imparting phase changes into said frequency-converting carrier signals which are related to phase changes in the chrominance subcarrier of the chrominance component in said SECAM television signal; and frequency-converting means supplied with said chrominance component of said SECAM television signal and the phase controlled frequency-converting carrier signals to produce frequency-converted chrominance components for recording in adjacent tracks having subcarrier phase changes eliminated therefrom in at least one track and having frequency-converted subcarriers in one track which differ from the frequency-converted subcarriers in an adjacent track.

Claim 3

The improvement of claim 1 wherein the frequency-converted subcarrier frequencies in adjacent tracks are in frequency interleaved relation with respect to each other.

Claim 4

The improvement of claim 2 wherein said phase control means comprises an injection-locked oscillator for producing an oscillating signal of substantially constant frequency; means for locking the phase of said oscillating signal produced by said injection-locked oscillator to the phase of the chrominance sub-carrier in each horizontal line interval of said SECAM television signal; and combining means for combining the phase-locked oscillating signal and the generated frequency-converting carrier signal to produce said phase controlled frequency-converting carrier signal.

Claim 5

The improvement of claim 3 wherein said means for generating a frequency-converting carrier signal comprises controllable oscillator means operable during the period that the SECAM composite color television signal is recorded in one track to produce a frequency-converting carrier signal of one frequency and operable during the period that the SECAM composite color television is recorded in the next adjacent track to produce a frequency-converting carrier signal of a different frequency, said different frequency differing from said one frequency by a factor n/4fh, wherein n is an integer and fh is the horizontal line frequency of said SECAM television signal; and wherein said combining means comprises a frequency converter supplied with said frequency-converting carrier signal produced by said controllable oscillator means and said phase-locked oscillating signal.

Claim 6

The improvement of claim 4 wherein said controllable oscillator means comprises a voltage-controlled oscillator; first and second frequency-dividers coupled to the output of said voltage-controlled oscillator for dividing the frequency of the output of said voltage-controlled oscillator by factors m 1 and m 2 , respectively; synchronizing signal separator means for separating the horizontal synchronizing signal from said SECAM television signal; phase comparator means coupled to said synchronizing signal separator means and to said first and second frequency-dividers for comparing the phase of said horizontal synchronizing signal to the phase of the frequency-divided output of said voltage-controlled oscillator to produce a control signal; means for selectively supplying to said phase comparator means said output of said voltage controlled oscillator, frequency-divided by the factor m 1 during the period that the SECAM composite color television signal is recorded in one track, and frequency-divided by the factor m 2 during the period that the SECAM composite color television signal is recorded in the next adjacent track; and means for supplying said control signal produced by said phase comparator means to said voltage-controlled oscillator.

Claim 7

The improvement of claim 5 further comprising another frequency-divider coupled to the output of said voltage-controlled oscillator for dividing the frequency of the output of said voltage-controlled oscillator by another factor m 3 and supplying same to said frequency-converter, wherein (m 1 -m 2 )/m 3 =n/4.

Claim 8

The improvement of claim 5 wherein said phase comparator means comprises a sawtooth waveform generator for generating a sawtooth waveform whose frequency is equal to the frequency of the output of said voltage-controlled oscillator divided by the factor m 1 or m 2 ; and sampling means responsive to said horizontal synchronizing signal for sampling said sawtooth waveform.

Claim 9

The improvement of claim 7 wherein said means for selectively supplying to said phase comparator means the frequency-divided output of said voltage-controlled oscillator comprises a switch having one input coupled to the output of said first frequency-divider, another input coupled to the output of said second frequency-divider, and an output connected to said sawtooth waveform generator and coupled to said one input during the period that the SECAM composite color television signal is recorded in one track, and to said other input during the period that the SECAM composite color television signal is recorded in the next adjacent track.

Claim 10

The improvement of claim 3 wherein said means for locking the phase of said oscillating signal produced by said injection locked oscillator comprises gating means operative during each horizontal line interval to pass the discriminating signal included in the SECAM composite color television signal to said injection locked oscillator.

Claim 11

The improvement of claim 9 wherein the frequency of the oscillating signal produced by said injection locked oscillator is equal to a predetermined frequency of the discriminating signal during certain ones of said horizontal line intervals; and said means for locking the phase of said oscillating signal produced by said injection locked oscillator further comprises means for shifting the frequency of the discriminating signal during other of said horizontal line intervals to said predetermined frequency prior to the passing thereof to said injection locked oscillator.

Claim 12

The improvement of claim 10 wherein said means for shifting the frequency of the discriminating signal during other of said horizontal line intervals comprises a sawtooth waveform generator for generating a sawtooth waveform only in each of said other horizontal line intervals during at least the period thereof that said discriminating signal is received; and phase modulating means for receiving at least the discriminating signal included in each of said horizontal line intervals for modulating the phase thereof with the output of said sawtooth waveform generator, whereby the phase modulation of the discriminating signal during said other horizontal line intervals results in a change in frequency thereof to said predetermined frequency.

Claim 13

The improvement of claim 11 further comprising pulse generating means for generating a pulse in substantial time coincidence with the back porch portion of each horizontal synchronizing interval of the SECAM composite color television signal, said pulse operating said gating means to pass either the discriminating signal or the frequency-shifted discriminating signal to said injection locked oscillator.

Claim 14

The improvement of claim 12 further comprising means for inhibiting the operation of said injection locked oscillator during the time of occurrence of the horizontal synchronizing pulse in the SECAM composite color television signal.

Claim 15

The improvement of claim 2 wherein said means for generating first and second frequency-converting carrier signals comprises reference generating means for generating a reference oscillating signal of substantially constant frequency; and phase inverting means for inverting the phase of said reference oscillating signal during selected horizontal line intervals, such that the phase of the subcarrier of the chrominance component of the recorded SECAM television signal is constant for all horizontal line intervals in one track and is inverted at successive groups of horizontal line intervals in the next adjacent track.

Claim 16

The improvement of claim 14 wherein said phase control means comprises switch means for selectively passing said reference oscillating signal and the phase-inverted reference oscillating signal to said frequency-converting means; and switch control means operative during the period that the SECAM composite color television signal is recorded in one track to control said switch means to supply said phase-inverted reference oscillating signal to said frequency-converting means during horizontal line intervals that the subcarrier of said chrominance component of the SECAM color television signal is phase-shifted relative to said subcarrier in adjacent horizontal line intervals and to supply said reference oscillating signal to said frequency-converting means during remaining horizontal line intervals, and operative during the period that the SECAM composite color television signal is recorded in the next adjacent track to periodically control said switch means to supply said phase-inverted reference oscillating signal to said frequency-converting means for a predetermined number of horizontal line intervals, and then to supply said reference oscillating signal followed by said phase-inverted reference oscillating signal to said frequency-converting means during the next successive horizontal line intervals, and then to supply said reference oscillating signal to said frequency-converting means of said predetermined number of horizontal line intervals, and then to supply said phase-inverted reference oscillating signal followed by said reference oscillating signal to said frequency-converting means during the next successive horizontal line intervals.

Claim 17

The improvement of claim 15 wherein said switch control means comprises synchronizing signal separator means for separating the horizontal synchronizing signal from said SECAM television signal; first counter means for counting said horizontal synchronizing signals to produce an output pulse for the duration of each horizontal line interval that said sub-carrier of said chrominance component is phase-shifted; second counter means for counting said horizontal synchronizing signals to produce a periodic signal whose frequency is an even sub-multiple of the horizontal line frequency during said period that the SECAM composite television signal is recorded in the next adjacent track, said second counter means being inhibited during said period that the SECAM composite color television signal is recorded in said one track; and means for combining said output pulse and said periodic signal to produce a switch control signal for controlling said switch means.

Claim 18

The improvement of claim 16 wherein said means for combining said output pulse and said periodic signal comprises an exclusive-OR circuit.

Claim 19

The improvement of claim 17 wherein the subcarrier of said chrominance component of the SECAM color television signal is phase-shifted during each third horizontal line interval; wherein said output pulse produced by said first counter means has a frequency that is one-third the horizontal line frequency; and wherein said periodic signal produced by said second counter means has a frequency that is one-fourth the horizontal line frequency.

Claim 20

The improvement of claim 16 further comprising counter control means responsive to said subcarrier of said chrominance component of the SECAM television signal to control said first counter means to produce said output pulse when said subcarrier is phase-shifted.

Claim 21

The improvement of claim 19 wherein said counter control means comprises phase inverting means for inverting the phase of said subcarrier of said chrominance component; switch means responsive to said ouput pulse to transmit either said subcarrier or the phase-inverted subcarrier; phase comparator means for comparing the phase of the present output of said switch means to the phase of a previous output of said switch means; and means responsive to said phase comparator means for terminating said output pulse in the event that said output pulse causes said switch means to transmit an incorrect phase-inverted subcarrier to said phase comparator means.

Claim 22

The improvement of claim 20 wherein said phase comparator means comprises a phase comparator having one input coupled to the output of said switch means and another input; and delay means coupled between the output of said switch means and said other input for supplying the output of said switch means, produced during a previous horizontal line interval, to said phase comparator.

Claim 23

The improvement of claim 21 further comprising inhibit means responsive to said means for terminating said output pulse for inhibiting subsequent operation of said means for terminating said output pulse for a predetermined time.

Claim 24

The improvement of claim 22 further comprising gate means for supplying only the discriminating signal included in each line interval of the SECAM television signal to said counter control means.

Claim 25

The improvement of claim 23 wherein said delay means imparts a delay equal to two horizontal line intervals such that the frequency of the delayed subcarrier signals is equal to the frequency of the undelayed subcarrier signal.

Claim 26

The improvement of claim 3 further including means for reproducing the SECAM composite color television signal recorded in each track together with a cross-talk component reproduced from an adjacent track; means for demodulating the reproduced luminance component substantially back to its original frequency range; frequency re-converting means responsive to re-converting signals for frequency re-converting the reproduced chrominance component substantially back to its original frequency range and for re-converting the reproduced cross-talk components; means for generating first and second re-converting signals of substantially equal and fixed phase, said first re-converting signal being supplied to said frequency re-converting means when the SECAM composite color television signal recorded in one track is reproduced and said second re-converting signal being supplied to said frequency re-converting means when the SECAM composite color television signal recorded in the next adjacent track is reproduced; comb filter means coupled to the output of said frequency re-converting means for substantially attenuating the reproduced cross-talk components; and means for re-combining the frequency re-converted chrominance component and the demodulated luminance component.

Claim 27

The improvement of claim 25 wherein said means for generating first and second re-converting signals comprises controllable oscillator means operable during the period that the SECAM composite color television signal recorded in one track is reproduced to produce a re-converting carrier signal of one frequency and operable during the period that the SECAM composite color television signal is recorded in the next adjacent track is reproduced to produce a re-converting carrier signal of a different frequency, said different frequency differing from said one frequency by a factor n/4fh, wherein n is an integer and fh is the horizontal line frequency of said SECAM television signal.

Claim 28

The improvement of claim 26 wherein said controllable oscillator means comprises a voltage-controlled oscillator; first and second frequency dividers coupled to the output of said voltage-controlled oscillator for dividing the frequency of the output of said voltage-controlled oscillator by factors m 1 and m 2 , respectively; synchronizing signal separator means for separating the horizontal synchronizing signal from the reproduced SECAM television signal; phase comparator means coupled to said synchronizing signal separator means and to said first and second frequency-dividers for comparing the phase of said horizontal synchronizing signal to the phase of the frequency-divided output of said voltage-controlled oscillator to produce a control signal; means for selectively supplying to said phase comparator means said output of said voltage controlled oscillator, frequency-divided by the factor m 1 during the period that the SECAM composite color television signal in one track is reproduced, and frequency-divided by the factor m 2 during the period that the SECAM composite color television signal recorded in the next adjacent track is reproduced; and means for supplying said control signal produced by said phase comparator means to said voltage-controlled oscillator.

Claim 29

The improvement of claim 27 further comprising another frequency-divider coupled to the output of said voltage-controlled oscillator for dividing the frequency of the output of said voltage-controlled oscillator by another factor m 3 ; and means for supplying the output of said voltage-controlled oscillator, frequency-divided by said factor m 3 , to said frequency re-converter means; and wherein (m 1 -m 2 )/m 3 =n/4.

Claim 30

The improvement of claim 27 wherein said phase comparator means comprises a sawtooth waveform generator for generating a sawtooth waveform whose frequency is equal to the frequency of the output of said voltage-controlled oscillator divided by the factor m 1 or m 2 ; and sampling means responsive to said horizontal synchronizing signal for sampling said sawtooth waveform.

Claim 31

The improvement of claim 29 wherein said means for selectively supplying to said phase comparator means the frequency-divided output of said voltage-controlled oscillator comprises a switch having one input coupled to the output of said first frequency-divider, another input coupled to the output of said second frequency-divider, and an output connected to said sawtooth waveform generator and coupled to said one input during the period that the SECAM composite color television signal recorded in one track is reproduced, and to said other input during the period that the SECAM composite color television signal recorded in the next adjacent track is reproduced.

Claim 32

The improvement of claim 26 wherein said means for generating first and second re-converting signals further comprises a reference oscillator for generating a reference oscillating signal whose frequency is substantially equal to the frequency of the oscillating signal produced by said injection-locked oscillator; and a frequency converter for combining said reference oscillating signal with the output of said controllable oscillator means, the combined signals being supplied to said frequency re-converting means.

Claim 33

The improvement of claim 15 further including means for reproducing the SECAM composite color television signal recorded in each track together with a cross-talk component reproduced from an adjacent track; means for demodulating the reproduced luminance component substantially back to its original frequency range; frequency re-converting means responsive to re-converting signals for frequency re-converting the reproduced chrominance component substantially back to its original frequency range and for re-converting the reproduced cross-talk components; means for generating a first re-converting signal of substantially constant frequency and phase and a second re-converting signal of said substantially constant frequency and whose phase is inverted at successive groups of horizontal line intervals of the reproduced SECAM television signal, said first re-converting signal being supplied to said frequency re-converting means when the SECAM television signal whose sub-carrier of the chrominance component is of constant phase for all horizontal line intervals is reproduced and said second re-converting signal being supplied to said frequency re-converting means when the SECAM television signal whose subcarrier of the chrominance component is of inverted phase at successive groups of horizontal line intervals is reproduced; comb filter means coupled to the output of said frequency re-converting means for substantially attenuating the reproduced cross-talk components; and means for re-combining the frequency re-converted chrominance component and the demodulated luminance component.

Claim 34

The improvement of claim 32 wherein the SECAM television signal recorded in said next adjacent track has the phase of the subcarrier of its chrominance component inverted at alternate horizontal line intervals; and wherein the phase of said second re-converting signal is opposite the phase of said subcarrier of the SECAM television signal recorded in said next adjacent track; whereby the phase of the frequency re-converted chrominance component is constant throughout each track.

Claim 35

The improvement of claim 33 wherein said means for generating first and second re-converting signals comprises reference oscillating means for generating a re-converting reference oscillating signal; phase inverting means for producing a phase-inverted re-converting reference oscillating signal; and controllable switch means for supplying to said frequency re-converting means said re-converting reference oscillating signal when said SECAM television signal having the subcarrier of constant phase for all horizontal line intervals is reproduced from said one track, and for selectively supplying to said frequency re-converting means when said SECAM television signal is reproduced from said next adjacent track said re-converting oscillating signal when the phase of the subcarrier of the reproduced chrominance component is inverted and said phase-inverted re-converting oscillating signal when the phase of the subcarrier of the reproduced chrominance component is not inverted.

Claim 36

The improvement of claim 34 wherein said controllable switch means comprises a switching circuit having inputs coupled to said reference oscillating means and to said phase inverting means, respectively, and an output coupled to said frequency re-converting means; and a switch control circuit comprising synchronizing signal separator means for separating the horizontal synchronizing signal from the reproduced SECAM television signal, a counter for counting said horizontal synchronizing signals to produce an output periodic signal whose frequency is one-fourth the frequency of said horizontal synchronizing signal, and means for inhibiting said counter when said SECAM television signal recorded in said next adjacent track is reproduced.

Claim 37

The improvement of claim 26 or 33 wherein said comb filter means comprises a delay circuit for delaying the frequency re-converted chrominance component a predetermined number of horizontal line intervals; and combining means for combining the delayed and undelayed chrominance components.

Claim 38

The improvement of claim 36 wherein said combining means comprises an adding circuit.

Claim 39

The improvement of claim 37 further comprising an attenuator for attenuating the chrominance component applied to said adding circuit from said delay circuit.

Claim 40

The improvement of claim 38 wherein said delay circuit delays the frequency re-converted chrominance component by two horizontal line intervals.

Claim 41

The improvement of claim 39 further comprising a subtractor for subtracting the undelayed chrominance component from the delayed chrominance component, the output from said subtractor being supplied to said attenuator.

Claim 42

The improvement of claim 1 wherein said SECAM composite color television signals are recorded in successive tracks with their horizontal synchronizing intervals in alignment.

Claim 43

The improvement of claim 1 wherein the adjacent tracks in which said SECAM composite color television signal is recorded are arranged without guard bands therebetween.

Claim 44

The improvement of claim 1 or 25 wherein said record medium is magnetic; first and second transducers are provided with different azimuth angles to scan successive tracks on said magnetic medium for recording and/or reproducing said SECAM composite color television signal in said one and adjacent tracks, respectively; and sensing means is provided to produce first and second indicating signals when said first and second transducers scan said one and adjacent tracks, respectively.

Claim 45

Apparatus for reproducing a SECAM composite color television signal which is recorded in successive parallel tracks on a record medium, the recorded SECAM television signal including a luminance component modulated to a relatively higher frequency range and a chrominance component frequency converted to a relatively lower frequency range, the chrominance component containing, in each horizontal line interval of said SECAM television signal, an unmodulated chrominance subcarrier discriminating signal and a modulated chrominance subcarrier color signal, the phase of the chrominance subcarrier in each horizontal line interval in a track being substantially constant and the frequency of the chrominance subcarrier in one horizontal line interval in one track differing from the frequency of the chrominance subcarrier in an adjacent horizontal line interval in the next adjacent track by n/4fh, where n is an odd integer and fh is the horizontal synchronizing frequency of said SECAM television signal, said apparatus comprising transducer means for scanning said successive tracks to reproduce the SECAM television signal recorded in the scanned track together with a cross-talk component of the SECAM television signal recorded in the track adjacent the scanned track; a luminance channel for demodulating the reproduced luminance component back to its original frequency range; a chrominance channel for re-converting the reproduced chrominance component back to its original frequency range; and combining means for combining the demodulated luminance component and the re-converted chrominance component; and wherein said chrominance channel comprises frequency re-converting means for receiving the reproduced chrominance component and chrominance cross-talk component, and responsive to re-converting signals for frequency re-converting said reproduced chrominance and chrominance cross-talk components; means for generating first and second re-converting signals of substantially constant and equal phase, the frequencies of said first and second re-converting signals differing from each other by n/4fh, the first re-converting signal being supplied to said frequency re-converting means when one track is scanned and the second re-converting signal being supplied to said frequency re-converting means when the next adjacent track is scanned; and comb filter means coupled to the output of said frequency re-converting means for substantially attenuating the frequency re-converted chrominance cross-talk component reproduced from each track.

Claim 46

Apparatus for reproducing a SECAM composite color television signal which is recorded in successive parallel tracks on a record medium, the recorded SECAM television signal including a luminance component modulated to a relatively higher frequency range and a chrominance component frequency converted to a relatively lower frequency range, the chrominance component containing, in each horizontal line interval of said SECAM television signal, an unmodulated chrominance subcarrier discriminating signal and a modulated chrominance subcarrier color signal, the phase of the chrominance subcarrier in each horizontal line interval in a track being substantially constant and the frequency of the chrominance subcarrier in one horizontal line interval in one track differing from the frequency of the chrominance subcarrier in an adjacent horizontal line interval in the next adjacent track by n/4fh, where n is an odd integer and fh is the horizontal synchronizing frequency of said SECAM television signal, said apparatus comprising transducer means for scanning said successive tracks to reproduce the SECAM television signal recorded in the scanned track together with a cross-talk component of the SECAM television signal recorded in the track adjacent the scanned track; a luminance channel for demodulating the reproduced luminance component back to its original frequency range; a chrominance channel for re-converting the reproduced chrominance component back to its original frequency range; and combining means for combining the demodulated luminance component and the re-converted chrominance component; and wherein said chrominance channel comprises frequency re-converting means for receiving the reproduced chrominance component and chrominance cross-talk component, and responsive to re-converting signals for frequency re-converting said reproduced chrominance and chrominance cross-talk components; means for generating first and second re-converting signals of substantially constant and equal phase, the frequencies of said first and second re-converting signals differing from each other by n/4fh, the first re-converting signal being supplied to said frequency re-converting means when one track is scanned and the second re-converting signal being supplied to said frequency re-converting means when the next adjacent track is scanned; and comb filter means coupled to the output of said frequency re-converting means for substantially attenuating the frequency re-converted chrominance cross-talk component reproduced from each track.

Claim 47

The apparatus of claim 44 wherein said comb filter means comprises a delay circuit for delaying the frequency re-converted chrominance and chrominance cross-talk components a predetermined number of horizontal line intervals; and means for combining the delayed and undelayed frequency re-converted chrominance and chrominance cross-talk components.

Claim 48

The apparatus of claim 45 wherein said means for combining the delayed and undelayed frequency re-converted chrominance and chrominance cross-talk components comprises an adding circuit.

Claim 49

The apparatus of claim 46 further comprising an attenuator for attenuating the output of said delay circuit supplied to said adding circuit.

Claim 50

The apparatus of claim 47 wherein said delay circuit delays the frequency re-converted chrominance and chrominance cross-talk components by two horizontal line intervals.

Claim 51

The apparatus of claim 44 wherein said comb filter means comprises a delay circuit for delaying the frequency re-converted chrominance and chrominance cross-talk components by two horizontal line intervals; subtracting means for subtracting the undelayed frequency re-converted chrominance and chrominance cross-talk components from the delayed frequency re-converted chrominance and chrominance cross-talk components; attenuating means for attenuating the output derived from said subtracting means by a predetermined amount; and an adding circuit for adding the output from said attenuating means and said undelayed frequency re-converted chrominance and chrominance cross-talk components.

Claim 52

The apparatus of claim 49 wherein said attenuating means attenuates the output derived from said subtracting means by a factor of one-half.

Claim 53

The apparatus of claim 44 wherein said means for generating first and second re-converting signals comprises sensing means for sensing when said transducer means scans said one track to produce a first sense signal and for sensing when said transducer means scans said adjacent track to produce a second sense signal; and automatic frequency control means responsive to said first sense signal for deriving said first re-converting signal and responsive to said second sense signal for deriving said second re-converting signal.

Claim 54

The apparatus of claim 51 wherein said automatic frequency control means comprises synchronizing signal separator means for separating the horizontal synchronizing signal from the demodulated luminance component of said reproduced SECAM television signal; controllable oscillator means for producing an oscillating signal whose frequency is greater than the frequency of said separated horizontal synchronizing signal; first and second frequency dividers for dividing the frequency of said oscillating signal by factors m 1 and m 2 , respectively, where m 1 -m 2 =2n; phase comparator means for comparing the phase of said separated horizontal synchronizing signal to the frequency-divided oscillating signal; and switch means responsive to said first sense signal for supplying the output of said first frequency divider to said phase comparator means and responsive to said second sense signal for supplying the output of said second frequency divider to said phase comparator means.

Claim 55

The apparatus of claim 52 wherein n=1, and further comprising a reference oscillator for supplying a reference oscillating signal whose frequency is equal to one of the chrominance subcarrier frequencies of said SECAM television signal; an additional frequency-divider for dividing the frequency of the oscillating signal produced by said controllable oscillator means by one-eighth; and a frequency converter supplied with said reference oscillating signal and said oscillating signal whose frequency is divided by one-eighth to produce said re-converting signals.

Claim 56

The apparatus of claim 52 further comprising means for interrupting the supply of the output from said comb filter means to said combining means from the beginning of the horizontal synchronizing interval of said reproduced SECAM television signal to the beginning of the back porch interval included in said horizontal synchronizing interval.

Claim 57

The apparatus of claim 44 wherein said successive parallel tracks are arranged on said record medium without guard bands therebetween; said record medium is magnetic; and said transducer means comprise first and second reproducing heads having different azimuth angles.

Claim 58

Apparatus for reproducing a SECAM composite color television signal which is recorded in successive parallel tracks on a record medium, the recorded SECAM television signal including a luminance component modulated to a relatively higher frequency range and a chrominance component frequency converted to a relatively lower frequency range, the chrominance component containing, in each horizontal line interval of said SECAM television signal, an unmodulated chrominance subcarrier discriminating signal and a modulated chrominance subcarrier color signal, the phase of the chrominance subcarrier in each horizontal line interval in one track being substantially constant and the phase of the chrominance subcarrier being inverted after each successive predetermined number of horizontal line intervals in the next adjacent track, and the frequency of the chrominance subcarrier alternating between two frequency values in successive horizontal line intervals in each track, said apparatus comprising transducer means for scanning said successive tracks to reproduce the SECAM television signal recorded in the scanned track together with a cross-talk component of the SECAM television signal recorded in the track adjacent the scanned track; a luminance channel for demodulating the reproduced luminance component back to its original frequency range; a chrominance channel for re-converting the reproduced chrominance component back to its original frequency range; and combining means for combining the demodulated luminance component and the re-converted chrominance component; and wherein said chrominance channel comprises frequency re-converting means for receiving the reproduced chrominance component and chrominance cross-talk component, and responsive to re-converting signals for frequency re-converting said reproduced chrominance and chrominance cross-talk components; means for generating first and second re-converting signals of substantially constant and equal frequency, the phase of said first re-converting signal being constant and the phase of said second re-converting signal being inverted after each successive predetermined number of horizontal line intervals, the first re-converting signal being supplied to said frequency re-converting means when said one track is scanned and the second re-converting signal being supplied to said frequency re-converting means when said next adjacent track is scanned; and comb filter means coupled to the output of said frequency re-converting means for substantially attenuating the frequency re-converted chrominance cross-talk component reproduced from each track.

Claim 59

Apparatus for reproducing a SECAM composite color television signal which is recorded in successive parallel tracks on a record medium, the recorded SECAM television signal including a luminance component modulated to a relatively higher frequency range and a chrominance component frequency converted to a relatively lower frequency range, the chrominance component containing, in each horizontal line interval of said SECAM television signal, an unmodulated chrominance subcarrier discriminating signal and a modulated chrominance subcarrier color signal, the phase of the chrominance subcarrier in each horizontal line interval in one track being substantially constant and the phase of the chrominance subcarrier being inverted after each successive predetermined number of horizontal line intervals in the next adjacent track, and the frequency of the chrominance subcarrier alternating between two frequency values in successive horizontal line intervals in each track, said apparatus comprising transducer means for scanning said successive tracks to reproduce the SECAM television signal recorded in the scanned track together with a cross-talk component of the SECAM television signal recorded in the track adjacent the scanned track; a luminance channel for demodulating the reproduced luminance component back to its original frequency range; a chrominance channel for re-converting the reproduced chrominance component back to its original frequency range; and combining means for combining the demodulated luminance component and the re-converted chrominance component; and wherein said chrominance channel comprises frequency re-converting means for receiving the reproduced chrominance component and chrominance cross-talk component, and responsive to re-converting signals for frequency re-converting said reproduced chrominance and chrominance cross-talk components; means for generating first and second re-converting signals of substantially constant and equal frequency, the phase of said first re-converting signal being constant and the phase of said second re-converting signal being inverted after each successive predetermined number of horizontal line intervals, the first re-converting signal being supplied to said frequency re-converting means when said one track is scanned and the second re-converting signal being supplied to said frequency re-converting means when said next adjacent track is scanned; and comb filter means coupled to the output of said frequency re-converting means for substantially attenuating the frequency re-converted chrominance cross-talk component reproduced from each track.

Claim 60

The apparatus of claim 56 wherein the phase of said second re-converting signal is opposite to the phase of the chrominance subcarrier recorded in said next adjacent track.

Claim 61

The apparatus of claim 56 wherein said comb filter means comprises a delay circuit for delaying the frequency reconverted chrominance and chrominance cross-talk components a predetermined number of horizontal line intervals; and means for combining the delayed and undelayed frequency re-converted chrominance and chrominance cross-talk components.

Claim 62

The apparatus of claim 58 wherein said means for combining the delayed and undelayed frequency re-converted chrominance and chrominance cross-talk components comprises an adding circuit.

Claim 63

The apparatus of claim 59 further comprising an attenuator for attenuating the output of said delay circuit supplied to said adding circuit.

Claim 64

The apparatus of claim 60 wherein the phase of the chrominance subcarrier recorded in said next adjacent track is inverted after every two horizontal line intervals; and wherein said delay circuit delays the frequency re-converted chrominance and chrominance cross-talk components by two horizontal line intervals.

Claim 65

The apparatus of claim 56 wherein the phase of the chrominance subcarrier recorded in said next adjacent track is inverted after every two horizontal line intervals; and wherein said comb filter means comprises a delay circuit for delaying the frequency re-converted chrominance and chrominance cross-talk components by two horizontal line intervals; subtracting means for subtracting the undelayed frequency re-converted chrominance and chrominance cross-talk components from the delayed frequency re-converted chrominance and chrominance cross-talk components; attenuating means for attenuating the output derived from said subtracting means by a predetermined amount; and an adding circuit for adding the output from said attenuating means and said undelayed frequency re-converted chrominance and chrominance cross-talk components.

Claim 66

The apparatus of claim 62 wherein said attenuating means attenuates the output derived from said subtracting means by a factor of one-half.

Claim 67

The apparatus of claim 56 wherein said means for generating first and second re-converting signals comprises sensing means for sensing when said transducer means scans said one track to produce a first sense signal and for sensing when said transducer means scans said adjacent track to produce a second sense signal; means for supplying an oscillating signal of said substantially constant frequency; phase inverting means for inverting the phase of said oscillating signal; controllable switch means for selectively supplying to said frequency re-converting means either said oscillating signal or the phase-inverted oscillating signal; and switch control means responsive to said first sense signal to control said switch means to supply said oscillating signal to said frequency re-converting means, and responsive to said second sense signal to control said switch means to supply said oscillating signal and then said phase-inverted oscillating signal to said frequency re-converting means each for two horizontal line intervals.

Claim 68

The apparatus of claim 64 wherein said switch control means comprises synchronizing separator means for separating the horizontal synchronizing signal from the demodulated luminance component of the reproduced SECAM television signal; and frequency divider means for dividing the frequency of said separated horizontal synchronizing signal by one-fourth to produce a periodic switch control signal.