Matsushita Electric Industrial Co., Ltd.

Sadafumi Kitamura

Hiroshi Taniguchi

Chojuro Yamamitsu

Masamitsu Ohtsu

Ichiro Arimura

Kenichi Hasegawa

Osahiko Yano

Norio Meki

Akira Miyamoto

A magnetic recording method for recording a multiplex signal having two different frequency signals. A magnetic recording medium is used having a magnetic layer with a thickness which is smaller than a recorded wavelength of each of said two signals. The signal of a higher frequency is recorded at a current which is more than 2dB larger than the lower limit of the recording current with which a reproduced output level is saturated, and which is smaller than a current with which the reproduced output level is reduced by 1dB beyond said saturated condition. The signal of a lower frequency is recorded at a current which is smaller than one half of that of the signal of a higher frequency.

Method for recording multiplexed signals on metal evaporated tape

In a magnetic recording and reproducing system of the type wherein a plurality of rotating magnetic heads record the video signal on a magnetic tape as tracks which are inclined at an angle relative to the direction of travel of the magnetic tape, the audio signal is time compressed and recorded by the rotating magnetic heads on tracks contiguous with either or both ends of said video signal recording tracks, whereby even at a considerably low tape transport speed the audio signal may be recorded in a stable manner.

Helical scan video tape recorder for recording video and audio signals

In a circuit including an amplifier for amplifying a small signal from a signal source wherein the inductance of a transducer and the capacitance of a capacitor form a resonance circuit, the output from the amplifier is negatively fed back through a resistor or a combination of resistors to the input of the amplifier, whereby the noise in the demodulated signal may be suppressed.

Preamplifier

A magnetic video recording and reproducing system in which a luminescence signal of a color television signal is frequency-modulated and a carrier chrominance signal is frequency-converted to a lower frequency side is disclosed, wherein during recording operation a burst signal of an input carrier chrominance signal is phase-compared with a signal from a variable frequency oscillator to produce an error signal which is used to control the variable frequency oscillator, and during playback operation a burst signal of a reproduced carrier chrominance signal is phase-compared with an output signal from a fixed frequency oscillator to produce an error signal which is used to control the variable frequency oscillator. During the recording operation, the burst signal of the input carrier chrominance signal and the signal from the variable frequency oscillator are applied as input to the detection circuit and during the playback operation the burst signal of the reproduced carrier chrominance signal and the signal from the fixed frequency oscillator are applied as inputs to the detecting circuit, to produce a phase-detected output which is used as a control signal for a color killer in order to assure a stable and reliable color killer operation with a low cost.

Magnetic color video recording and reproducing system with color killer

A magnetic recording and reproducing system which separates a brightness signal and a carrier color signal from a color television signal, frequency modulates the brightness signal and converts the carrier color signal to a lower frequency, records the modulated brightness signal and the low frequency carrier color signal in different manner for each horizontal scan line such that phases of the carrier are different between adjacent record tracks, and plays back the recorded signal through a comb filter to eliminate crosstalk from adjacent tracks in the carrier color signal. In this system, a horizontal synch. signal is eliminated in response to the detection of dropouts so as to prevent the disturbance of AFC and APC loops by dropouts, which would otherwise create color irregularity, and the horizontal synch. signal free of noise due to dropouts is used to activate the AFC and APC loops.

Growing community of inventors

Neyagawa, Japan

Sadafumi Kitamura