Abstract: A method for controlling to keep off defects in a magnetic disk apparatus while has a plurality of magnetic disks and defect position information is recorded in each of tracks on each magnetic disk to keep off a defect in writing records in each track. Positional information about defects on all the tracks belonging to a cylinder of the magnetic disk apparatus is recorded in each of the tracks, and records are written in each of the tracks while keeping off the defects on the basis of the recorded positional information about the defects.

Abstract: In a slow reproducing apparatus, a magnetic tape is intermittently driven. In a tape stop state during the intermittent drive operation, a video signal for one field is written in a field memory, and in a tape moving state during the intermittent driving operation, the written signal is read out from the field memory. A means for correcting a read timing error of the video signal caused by a variation in tape stop position during the intermittent driving operation is used, thus obtaining a noiseless, stable, slow reproduced image.

Abstract: An apparatus for controlling data transfer between a rotary storage device such as a magnetic disk having a plurality of heads for different tracks and another storage device such as a disk cache includes a plurality of transfer circuits for the purpose of simultaneous data transfer to and from a plurality of tracks. The transfer circuits operate concurrently with and independently of each other to transfer data therethrough and other than noting the regions to be skipped over, ignoring data format on the track. The apparatus is suitable for preloading a disk cache from a disk.

Abstract: An image memory control device for a video signal special reproduction system comprises a write-in section for writing in a video signal including a signal wherein the number of horizontal scan lines per field period is a multiple of 0.5 or not a multiple of 0.

Abstract: Disclosed is a water-repellent nonwoven fabric made of a melt-blown fiber having a single filament denier of 0.005 to 2.0, wherein the fiber packing ratio is 5 to 70% and the water pressure rresistance index is 400 to 2,000 mmH.sub.2 O. The nonwoven fabric is used for an oil-water separating filter having a permeability to oil and non-permeability to water. A composite fabric comprising a combination of the nonwoven fabric and an air-permeable knitted or woven fabric laminated and integrated with at least one surface of the nonwoven fabric is useful as an air permeable and water repellent fabric.

Abstract: Disclosed is a water-repellent nonwoven fabric made of a melt-blown fiber having a single filament denier of 0.005 to 2.0, wherein the fiber packing ratio is 5 to 70% and the water pressure resistance index is 400 to 2,000 mmH.sub.2 O. The nonwoven fabric is used for an oil-water separating filter having a permeability to oil and non-permeability to water. A composite fabric comprising a combination of the nonwoven fabric and an air-permeable knitted or woven fabric laminated and integrated with at least one surface of the nonwoven fabric is useful as an air permeable and water repellent fabric.

Abstract: The invention provides an encoder for subjecting an input signal to the orthogonal transform for band compression and encoding. The encoder has a sample and hold circuit which samples the input signal at a sampling frequency three times that of the input signal, and an orthogonal transform unit which subjects the sampled signal to the orthogonal transform using as a coefficient an orthogonal matrix function of the order of 3n (where n is an integer of 2 or more) having as a minor matrix an orthogonal matrix of the order of 3: ##EQU1## having given numbers a, b and c as matrix elements. By maintaining the sampling frequency low, the frequency components of the input signal may be concentrated in a small number of transform outputs without causing an increase in the amount of data to be processed, without using a multiplier and without requiring an increase in the processing speed. The input signal is thus effectively band compressed and encoded.

Abstract: A control apparatus for a recording/playback system using an endless recording medium having a position detecting mark attached thereto and driven at a given speed to move along an endless loop, wherein the position detecting mark is detected as the recording medium is driven and a mark position signal generated to indicate each passage of the mark passed a predetermined point in the endless loop. Recording or playback operation is controlled based on the time between detection of successive mark position signals which is indicative of the one-cycle length of the recording medium. The one-cycle length of the endless recording medium is stored as data which may be changed upon changing of the tape length and/or the tape speed. Once the one-cycle length data is stored, automatic recording may be started from any position on the endless recording medium at any time.

Abstract: A position shift apparatus having an actuator section for moving up and down a magnetic head through a screw feeding, and a control section in which, when the screw feeding is made in the up direction, it is made by a given distance up to target position and, when in the down direction, it is made beyond the target position, and then is again made by the distance exceeding the target position in the up direction. Even if the head is positioned on either the lower or the upper side, the head is screw-fed toward the target position always in the up direction.

Abstract: A tape cassette comprises a case open at its top and having a tape-loaded reel rotationally mounted therein, a cover slidably opening and closing the opening of the case in a sidewise direction, and a pair of tape delivery members mounted on the forward portion of the cover to permit the part of the tape to be delivered merely upon withdrawal of the covering.