Abstract: The present invention relates to an industrial synthetic method of an optically active cyclohexane ether compound (IIIa) or a salt thereof, which is useful as a pharmaceutical agent, and an intermediate useful for the production method of the present invention. The production method of the present invention is as shown below: wherein each symbol is as defined in the specification. According to the production method of the present invention, efficient and stable supply of an optically active cyclohexane ether compound (IIIa) in a high yield at a lower cost can be afforded. Therefore, an optically active cyclohexane ether compound (IIIa) extremely useful as a pharmaceutical agent can be provided by an industrially highly advantageous method.

Abstract: This invention provides a novel process for the preparation of a 3-acylindole or the salt thereof in a high yield.

Abstract: In a magnetic head including metal magnetic films in a gap forming part thereof, among track edges included in the gap part of the magnetic head, track edges located on the side where record patterns are overwritten into a recording medium are so formed as to have a cut end face, and a reinforcing glass filled part is provided on the recording medium contact surface of the cut end face.

Abstract: A video tape recorder monitors the signal immediately after it has been recorded to determine whether errors have occurred in the recorded signal rerecords the video signal in the same location in the tracks where the error occurred. The location requiring rerecording can be located by recording a time code along with the video signal as it is recorded and rewinding the tape to the location where the error occurs and recording a stored video signal at that location or the video signal can be delayed and rerecorded downstream using another recording head once an error has been detected using an error detector.

Abstract: In a video tape recorder, recording and reproducing heads record and reproduce a recording signal on recording tracks which are diagonally formed one after another on a tape-like recording medium. The recording heads are capable of recording again the same recording signal in the same recording region. If a recording error occurs during recording mode, information on where the recording error has occurred and a recording signal to be recorded are stored in a memory. During rerecording mode, the stored information is used to complement the recording error. If a recording error occurs, preliminary recording circuitry operates so as to complement this recording error. The above construction permits the recording signal to be recorded on the recording tracks with certainty.

Abstract: A tape cassette is provided with a slider serving as a reel lock releasing element and which is movable in the front-to-rear direction near the rear of the cassette, along a path defined by a guide. A guide groove is formed in the underside of the cassette in alignment with the guide for the slider. The slider has a downward projection extending into the guide groove through an elongated opening in the guide. The downward projection is abutted by a projection built into the playback unit, and which is received in the guide groove for guiding the cassette during its insertion into the playback unit or VTR. Therefore, insertion of the cassette causes the cassette guiding projection to displace the slider for releasing the tape reels.

Abstract: A multi-channel recording and/or reproducing apparatus is disclosed, wherein a plurality of rotary magnetic heads scan a magnetic tape to form a plurality of skewed parallel tracks simultaneously. These heads are aligned substantially in the scanning direction on a single head base plate. Preferably, these heads are so secured as to form parallel skewed tracks without guardbands therebetween. Each head has the same thickness, and is mounted on a head base. Even though the thickness of each head chip is the same, effective head gaps are formed to have different heights individually from the surface of the head base plate. When forming guardband-less plural tracks, an azimuth recording technique is introduced in order to avoid crosstalk between adjacent channels during reproduction.