摘要:
In a video signal recording/reproducing apparatus for recording and reproducing two-channel component signals, input two-channel component signals are processed separately from each other by two recording signal processing circuits to be recordable two-channel component signals. The recordable two-channel component signals are exchanged at predetermined intervals by a first switching circuit to be two combined signal each containing the recordable two-channel component signals which appear at periods corresponding to the exchanging invervals. The two combined signals are recorded on a recording medium via recording heads and reproduced from the recording medium via reproducing heads. The reproduced two combined signals are exchanged at the predetermined intervals by a second switching circuit to be the recordable two-channel component signals, which are thereafter processed separately from each other by two reproduced signal processing circuit to be the original two-channel component signals.
摘要:
A video tape recorder which records video signals on a magnetic tape in such a manner that a first signal having luminance information and a second signal having chrominance information are recorded alternately on each track and the first signal recorded on each track is adjacent to the first signal recorded on an adjacent track and the second signal recorded on each track is adjacent to the second signal recorded on the adjacent track. The first signal and the second signal are exchanged every predetermined period L to obtain two combined signals each composed of the first and second signals which occur alternately at intervals of the predetermined period L.
摘要:
A video signal recording/reproducing apparatus has, in a recording signal processing section, a first switching circuit for exchanging 2-channel component signals at intervals of nH (n: any integer, H: horizontal scanning period) to obtain two combined signals each containing the 2-channel component signals which appear alternately at periods of nH, and a first delay circuit for delaying one of the two combined signals by nH so that the same kind of signals appear at same timings in the two combined signals. The two combined signals one of which is delayed by nH will not be interfered with each other by crosstalks therebetween which will occur in the subsequent circuits including recording and reproducing heads. A reproduced signal processing section has a second delay circuit for delaying by nH a reproduced combined signal which corresponds to the combined signal which has not been delayed in the recording signal processing section so as to recover the original timing relation between reproduced two combined signals, and a second switching circuit for exchanging the reproduced two combined signals one of which is delayed by nH by the second delay circuit at intervals of nH to obtain the original 2-channel component signals.
摘要:
A signal processing apparatus for changing the frequency characteristics of an input signal, e.g.--a video or audio signal, allows a signal to pass through a transmission circuit in a positive time sequence and then, allows the signal to be transmitted through another transmission circuit having the same transmission characteristics in a reverse time sequence with respect to the positive time sequence. Also, while the transmission circuit is arranged to have a zero-phase characteristic, each segment of a continuous signal is processed throughout a period which is equal to at least two times a duration of an impulse response direction of the transmission circuit. Accordingly, unwanted wave errors appearing at discontinuous regions of the signals are eliminated.
摘要:
A PLL circuit for a phase comparator, a low-pass filter (LPF), a voltage-controlled oscillator (VCO) and a frequency divider. A first control circuit is responsive to a discontinuous phase change of a reference signal of the PLL circuit for inhibiting the operation of the phase comparator or disconnecting the LPF from the phase comparator during a predetermined period so that the discontinuous phase change information is not transmitted through the LPF to the VCO. At the same time, a second control circuit resets the frequency divider by a pulse of the reference signal after the discontinuous phase change or applies a voltage corresponding to the discontinuous phase change to the VCO so that the output signal of the frequency divider is locked in phase to the reference signal after the discontinuous phase change. With the cooperation of the first and second control circuits, the PLL circuit quickly recovers its stable state after the discontinuous phase change of the reference signal.
摘要:
A magnetic tape recording/reproducing apparatus for recording video signals on a magnetic tape without providing a guard band between each two adjacent signal tracks. The apparatus comprises a first switching circuit for exchanging 2-channel component signals every nH period to obtain two combined signals each composed of the 2-channel signals which alternate every nH period, two modulators for modulating the two combined signals, a head section having two pairs of rotarty magnetic heads for recording the modulated signals on the magnetic tape so that each two adjacent blocks contain a same channel component signal and for reproducing the recorded signals from the magnetic tape, two demodulators for demodulating the reproduced signals, and a second switching circuit for exchanging the demodulated signals every nH to obtain the 2-channel component signals. With this arrangement, the recording density is remarkably increased and the cross talk interference hardly occur.
摘要:
A magnetic tape recording/reproducing apparatus comprises a recording signal processing section, a head section, and a reproduced signal processing section. The recording signal processing section comprises a plurality of recording signal processing circuits each for converting a video signal to one or more recordable signals, and a first switch circuit for selectively connecting one of the recording signal processing circuits to the head section. The head section has a plurality of magnetic heads mounted on a single rotary cylinder for recording the recordable signals on a magnetic tape and reproducing the recorded signals from the magnetic tape. The reproduced signal processing section comprises a plurality of reproduced signal processing circuits each for converting the reproduced signals to the original video signal, a second switch circuit for selectively connecting one of the reproduced signal processing circuits to the head section, and a recognition circuit for recognizing what kind of signals are reproduced from the head section and producing a control signal for controlling the second switch circuit.
摘要:
A video signal reproduction apparatus for reproducing a composite color video signal from a recording medium. A signal reproduced from the recording medium is divided into a frequency-modulated (FM) signal and a low-band-converted signal by filters. The FM signal is demodulated by a demodulater into a luminance signal. A first conversion circuit produces from the low-band-converted signal a chrominance signal without a phase jitter component. A second conversion circuit produces from the low-band-converted signal a high-band component of luminance signal with a same phase jitter component as that of the luminance signal obtained from the demodulator. The luminance signal from the demodulator, the high-band component of luminance signal and the chrominance signal are mixed to obtain the composite color video signal.
摘要:
A video signal recording/reproducing apparatus includes a first set of rotary heads mounted on a rotary disk and a second set of rotary heads mounted on head actuators which are also mounted on the rotary disk. The apparatus has two reproduction modes. A magnetic tape in the first reproduction mode is driven at a speed equal to the speed used in a recording mode. The magnetic tape in the second reproduction mode is driven at a speed which is different from the speed used in the recording mode. The apparatus has a negative feedback loop which detects the reproduced signal level of the second set of rotary heads and drives the head actuators in order to increase the reproduced signal level of the second set of rotary heads. In the first reproduction mode, the negative feedback loop is intermittently closed. At the period of time when the negative feedback loop is open, the negative feedback loop holds the value of its output signal to that of the last time period when the negative feedback loop was closed, and, in addition, the head actuator is not driven when the feedback loop is open. At a transitional period when the apparatus switches from the first reproduction mode to the second reproduction mode, a holding signal from the negative feedback loop is supplied to the head actuator.