Nippon Hoso' Kyokai

Matsushita Electric Industrial Co., Ltd.

Yoshinobu Oba

Toshihiro Uehara

Kunio Sekimoto

Sigekazu Togashi

Tadashi Nakayama

Kunio Suesada

Hotaka Minaguchi

Hideo Oshima

Kunjo Suesada

A recording apparatus of the present invention includes selective guard adding means for predicting, at the time of editing, positions of adjacency of new tracks to previously recorded tracks obtained at the time of completion of new track recording, and adds, at the time of editing, guards to locations where disturbance due to residue of erasing of the same azimuth might occur in order to remove or reduce the disturbance due to residue of erasing of the same azimuth caused at the editing point. When performing reproduction from a recording medium whereon tracks recorded by heads of at least two kinds of azimuth angles are disposed alternately and a plurality of tracks are handled as one recording unit and recorded, a reproducing apparatus of the present invention is so configured that the center of each of heads located at both ends of reproducing heads may be shifted to the inside as compared with each corresponding recording track. When disturbance due to the residue of erasing of the same azimuth occurs at the editing point, therefore, more signals of tracks to be originally reproduced can be reproduced, resulting in a greater resistance to disturbance of the same azimuth.

Magnetic reproducing apparatus and magnetic recording and reproducing

An apparatus for generating a high speed dubbing signal to be recorded by an external recording apparatus. The high speed dubbing signal, whose pitch is N times that of a digital input signal, is generated as follows. An encoding circuit subsamples the digital input signal consisting of frame signals each of which consists of N field signals, so that each frame signal is compressed by a factor of N to be contained in one field interval. A digital signal recording and reproducing circuit including a recording and reproduction system, records on a tape, at a normal tape speed and at a normal head drum rotational frequency, the compressed signal in such a manner that each field including the compressed signal appears once per frame interval, and then selectively reproduces from the tape the field including the compressed signal at a tape speed N times the normal speed and at the normal drum speed. A decoding circuit interpolates the output signal of the recording and reproducing portion to recover the lost information by the subsampling. An output portion produces the high speed dubbing signal based on the output of the decoding circuit. Since the drum rotational frequency is maintained at the normal value throughout the recording and reproduction procedure by the recording and reproduction system, the contact between the tape and head of the system is stabilized, thereby enabling reliable high speed dubbing.

Apparatus and method for generating high speed dubbing signal

Magnetic reproducing apparatus and magnetic recording apparatus with

A digital modulation method for modulating 8-bit digital data into 14-bit digital modulation codes. The number of consecutive identical bits in a series of 14-bit digital modulation codes is restricted to 2-7. The absolute value of DSV at the end of each 14-bit digital modulation code is restricted to 2 or less, and the absolute value of DSV at each bit of any 14-bit digital modulation codes is limited to 7 or less. The direct current component of the 14-bit modulation codes can be effectively reduced.

Digital modulation method

Growing community of inventors

Atsugi, Japan

Yoshinobu Oba