Abstract: Apparatus and method for reproducing data from a CD-ROM at a constant angular velocity and for recording and reproducing data to and from a magneto-optical compact disc (CD-MO) at a constant angular velocity. Data reproduced from the CD-ROM is demodulated in accordance with an amount of reproduction time of a sync signal contained in the reproduced data. The clock rate of data to be recorded to or reproduced from the CD-MO is determined in accordance with the position or zone on the CD-MO at which the data is to be recorded or from which it is reproduced. The position or zone may be identified by address data which is reproduced from the CD-MO. In addition, a constant rotational velocity of the CD-MO is maintained by measuring an amount of reproduction time of the address data and varying the rotational velocity of the CD-MO in accordance with the measured reproduction time.

Abstract: A disk storage medium, for example, a magneto-optical compact disk, includes a plurality of data areas that have data stored therein and a plurality of address areas each associated with a respective data area and that have address data stored therein. The data in each of the data areas are stored at respectively different clock rates, and all of the address data in all of the address areas are stored at the same constant clock rate.

Abstract: Apparatus and method for reproducing data from a CD-ROM at a constant angular velocity and for recording and reproducing data to and from a magneto-optical compact disc (CD-MO) at a constant angular velocity. Data reproduced from the CD-ROM is demodulated in accordance with an amount of reproduction time of a sync signal contained in the reproduced data. The clock rate of data to be recorded to or reproduced from the CD-MO is determined in accordance with the position or zone on the CD-MO at which the data is to be recorded or from which it is reproduced. The position or zone may be identified by address data which is reproduced from the CD-MO. In addition, a constant rotational velocity of the CD-MO is maintained by measuring an amount of reproduction time of the address data and varying the rotational velocity of the CD-MO in accordance with the measured reproduction time.

Abstract: A recording and/or reproducing device for a disk enclosed in a cassette is disclosed. The device is comprised of a chassis, bearing members included in the chassis, a spindle mounted by these bearing members for rotation with respect to the chassis, a magnet holder mounted to the spindle, a rotor magnet mounted to the magnet holder and rotatable with respect to be chassis, a substrate affixed to the chassis, a stator coil mounted in the confronting relation to the rotor magnet on the base board, a turntable mounted to the upper part of the spindle, and a cassette holder mounted on the chassis and which is movable, for mounting the disk cassette to the turntable, between an inoperative position to be assumed when the disk cassette is inserted into or detached from the recording and/or reproducing device and an operative position to be assumed when the disk cassette is mounted on the turntable.

Abstract: Apparatus is provided for indicating the amount of tape wound upon a reel, such as a supply reel or a take-up reel, in a two-reel cartridge when the cartridge is loaded into a processing device of the type which includes a loading device for withdrawing from the cartridge a portion of the tape wound upon the reel. A signal is generated representing the angular velocity of the reel when that reel rotates in response to the withdrawal of tape from the cartridge. This generated signal is combined with predetermined signals representing predetermined characteristics of the tape, the combined signals then being used to indicate the amount of tape which is wound upon the reel. In a preferred embodiment, the predetermined signals are: v, the velocity of the tape as it is unwound from the reel; .delta., the thickness of the tape; R.sub.H, the diameter of the innermost winding of the tape upon the reel; and the signal which represents the angular velocity of the tape is P.sub.S.

Abstract: A time switching power saving system for electronic indicators which comprises an indicator operated by a battery and a time switching indication control circuit for controlling the operation of the indicator in such a manner that the indicator makes a continuous indication for a predetermined time period from the start of indication and then makes an intermittent indication after the predetermined time period has passed, so that the power consumption of the circuit is decreased without stopping the operation of the indicator.