Patents by Inventor Sadafumi Kitamura

Sadafumi Kitamura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4380779
    Abstract: 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.
    Type: Grant
    Filed: March 23, 1981
    Date of Patent: April 19, 1983
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Sadafumi Kitamura, Hiroshi Taniguchi
  • Patent number: 4303950
    Abstract: 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.
    Type: Grant
    Filed: July 12, 1979
    Date of Patent: December 1, 1981
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroshi Taniguchi, Osahiko Yano, Chojuro Yamamitsu, Sadafumi Kitamura, Masamitsu Ohtsu
  • Patent number: 4240038
    Abstract: 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.
    Type: Grant
    Filed: March 13, 1978
    Date of Patent: December 16, 1980
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kenichi Hasegawa, Hiroshi Taniguchi, Sadafumi Kitamura
  • Patent number: 4209800
    Abstract: 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.
    Type: Grant
    Filed: July 3, 1978
    Date of Patent: June 24, 1980
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Chojuro Yamamitsu, Sadafumi Kitamura, Akira Miyamoto
  • Patent number: 4137547
    Abstract: 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.
    Type: Grant
    Filed: October 17, 1977
    Date of Patent: January 30, 1979
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Chojuro Yamamitsu, Ichiro Arimura, Sadafumi Kitamura, Norio Meki