Abstract: Processing wherein a measurement signal and an erasure signal are recorded on adjacent tracks of a recordable tape 10 by one recording head HWi of n (i=1 to n) recording heads is effected on n recording heads, and measurement signals are recorded on n tracks substantially simultaneously by n recording heads HW1 to HWn in standard operation state. Then, reproducing heads with respect to thus obtained two kinds of tracks are displaced in track width directions, characteristic curves of reproduced signal waveform amplitudes of measurement signals displacement (off-track) amounts of tracks are obtained, half widths of these characteristic curves are assumed to be expedient track width and a variable Ri optimum and a variable Ri now corresponding to track widths of two kinds of tracks are obtained. Then, deviation between the variable Ri optimum and the variable Ri now is adjusted to become smaller than a desired value.

Abstract: Disclosed is a head system including a plurality of recording heads for azimuth recording. The system includes a first recording head having a plurality of magnetic gaps having a first azimuth angle, and a second recording head having a plurality of magnetic gaps having a second azimuth angle different from the first azimuth angle. After first magnetization patterns are formed on a recording medium by the first recording head, second magnetization patterns are formed by overwriting side edge portions in the formation direction of the first magnetization patterns by the second recording head. This makes it possible to prevent the worsening of the accuracy of the magnetization pattern width due to a relative height stagger (offset) between the heads, to thereby enhance the accuracy of the magnetization pattern width, and to achieve high-density recording.

Abstract: Processing wherein a measurement signal and an erasure signal are recorded on adjacent tracks of a recordable tape 10 by one recording head HWi of n (i=1 to n) recording heads is effected on n recording heads, and measurement signals are recorded on n tracks substantially simultaneously by n recording heads HW1 to HWn in standard operation state. Then, reproducing heads with respect to thus obtained two kinds of tracks are displaced in track width directions, characteristic curves of reproduced signal waveform amplitudes of measurement signals displacement (off-track) amounts of tracks are obtained, half widths of these characteristic curves are assumed to be expedient track width and a variable Ri optimum and a variable Ri now corresponding to track widths of two kinds of tracks are obtained. Then, deviation between the variable Ri optimum and the variable Ri now is adjusted to become smaller than a desired value.

Abstract: A magnetic head mounted on a rotary head drum device comprises a head chip, and a magnetic shield disposed to surround all or a part of the surfaces other than a front surface of the head chip. The magnetic shield comprises a magnetic flux absorber made of ferrite and an electromagnetic wave shield made of copper. This enables a reduction of the amount of unnecessary magnetic fluxes and electromagnetic waves jumping away from the recording head to the reproducing head. Simultaneously, the magnetic flux absorber absorbs the magnetic flux coming from outside to the reproducing head before the magnetic flux reaches the head chip and the electromagnetic wave shield shields a high frequency electromagnetic wave which was not absorbed by the magnetic flux absorber 80 that it is possible to reduce the amount of the magnetic flux or the like jumping into the reproducing head and to improve the S/N of the reproduced signal.

Abstract: Disclosed is a head system including a plurality of recording heads for azimuth recording. The system includes a first recording head having a plurality of magnetic gaps having a first azimuth angle, and a second recording head having a plurality of magnetic gaps having a second azimuth angle different from the first azimuth angle. After first magnetization patterns are formed on a recording medium by the first recording head, second magnetization patterns are formed by overwriting side edge portions in the formation direction of the first magnetization patterns by the second recording head. This makes it possible to prevent worsening of the accuracy of magnetization pattern width due to a relative height stagger (offset) between the heads, to thereby enhance the accuracy of the magnetization pattern width, and to achieve high-density recording.

Abstract: A magnetic head mounted on a rotary head drum device comprises a head chip, and a magnetic shield disposed to surround all or a part of surfaces other than a front surface of the head chip. The magnetic shield comprises a magnetic flux absorber made of ferrite and an electromagnetic wave shield made of copper. This enables reduction of the amount of unnecessary magnetic fluxes and electromagnetic waves jumping away from the recording head to the reproducing head. Simultaneously, the magnetic flux absorber absorbs the magnetic flux coming from outside to the reproducing head before the magnetic flux reaches the head chip and the electromagnetic wave shield shields a high frequency electromagnetic wave which was not absorbed by the magnetic flux absorber so that it is possible to reduce the amount of the magnetic flux or the like jumping into the reproducing head and to improve the S/N of the reproduced signal.

Abstract: A device that records and reproduces data using a tape driver and a tape guide drum with an angled rotary magnetic head for forming helical slant tracks for high density recording provides reverse data reproduction and synchronization, regardless of the helical-scanning system used for recording and reproduction, and accommodates error correction codes, to rapidly and accurately reproduce data at various speeds, formats, and error correction codes. The tape guide drum can rotate in both forward and reverse, so that access time is minimized because the tape needs no rewinding prior to playback. The capabilities of reverse direction playback, of handling data other than video data, and of reproducing data at arbitrary speeds provide flexibility for many applications, including a satellite's requirements for rapid, variable-speed playback and transmission of high-density, non-video data.

Abstract: An analog to digital converter is disclosed, in which an analog input voltage is converted by a first analog to digital converter to a digital signal of m-bits, the digital signal is code-converted to a digital signal, this code-converted digital signal is converted by a digital to analog converter to an analog voltage, the difference between the last analog voltage and the above analog input voltage is converted by a second analog to digital converter to a digital signal of n-bits, and this digital signal of n-bits and the above code-converted digital signal are added to each other to provide a digital signal of (m+n) bits which corresponds to the analog input voltage.

Abstract: Reference logical data is spatially divided by a data dividing circuit for each time slot, and the divided data are converted into data, each having a continuous effective period. The divided and converted reference data and input logical data are compared by comparators to detect whether or not they are coincident with each other. A clock signal for determining the timing of comparison is also divided by a clock signal dividing circuit into n clock signals which are displaced one time slot apart in phase and occurring with a period of n time slots. By these divided clock signals those of the outputs from the comparators corresponding thereto are taken out from a comparison output circuit.