Abstract: An input is ciphered in at least one of a sector forming circuit 13, a scrambling circuit 14, a header appendage circuit 15, an error correction encoding circuit 16, a modulation circuit 18 and a synchronization appendage circuit 18, used for processing input data for forming a recording signal. Not only key for ciphering itself in the circuits but also the information as to which of the circuits has been used for ciphering becomes the key for ciphering. This realizes ciphering difficult to decode by a simplified structure.

Abstract: An information communication system that includes a transmitter, a communication network and at least one terminal apparatus connected with the transmitter through the communication network. The transmitter transmits information to be offered to users. The transmitter includes an adding circuit and a selecting circuit. The adding circuit adds an identification code regarding distribution of the information. The transmitter transmits first and second pieces of information having different kinds of identification code. The terminal apparatus receives the information transmitted from the transmitter. The terminal apparatus also includes storing device for storing the transmitted information.

Abstract: An optical disk D is composed of a first recording layer L.sub.1 and a second recording layer L.sub.2 each for two recording formats. Encrypted data is recorded on the first recording layer L.sub.1. Encrypting key data is recorded on the second recording layer L.sub.2. The encrypting key data is used for decoding the encrypted data. This recording makes easy reproduction of the recorded data quite difficult. If data recorded on a bit-formed portion may be reproduced by any means, the data signal recorded on the optical disk cannot be easily reproduced.

Abstract: To enable management by a center of data transferred to a user terminal from the center, an ISDN, which has a call connecting means which forms a signal channel before forming a data channel between a user terminal and center and enable user to user transfer of data on that signal channel. In the control routine, control data regarding data management which prohibits or releases copying or reediting between a center and user is transferred between the center and user terminal. The data after transfer to the user terminal can also be managed from the center.

Abstract: In a database accessing system, access information concerning access to a database system is transferred using call control messages including user-to-user information within a control procedure defining the connection of a call on a signal channel. This results in a database accessing method that offers the improved use efficiencies of communication lines and the upgraded operating ratio of a database system, and allows users to enjoy reduced communication charges.

Abstract: In a database accessing system, access information concerning access to a database system is transferred using call control messages including user-to-user information within a control procedure defining the connection of a call on a signal channel. This results in a database accessing method that offers the improved use efficiencies of communication lines and the upgraded operating ratio of a database system, and allows users to enjoy reduced communication charges.

Abstract: A tape cassette for holding a magnetic tape which is constituted by an upper half and a lower half which define a cassette case and a tape guide located therein, wherein at least one of the upper half, the lower half and the tape guide is made of material containing ceramics.

Abstract: A tone arm assembly for record players has first and second electro-magnetic motors operable for swinging a tone arm in vertical and horizontal directions, respectively, in respect to a record disc on a turntable, and a control circuit for controlling the first and second motors in such a manner that the tone arm is moved from a raised inoperative position to a lowered playing position, or from the lowered playing position to the raised inoperative position in response to control signals.

Abstract: There are provided a current detecting resistance element connected in series with a loop for supplying current to a telephone set, a switching circuit including a three terminal semiconductor switching element connected to be ON.OFF controlled by the voltage drop across the resistance element, and an impedance element controlled by the ON.OFF operation of the switching element to be connected across the loop for adding AC loss.

Abstract: A tone arm assembly for record players having a first motor for rotating a tone arm in the vertical direction, a second motor for rotating the tone arm in the horizontal direction with respect to a record disc, respectively, a detector for detecting low frequency vertical and horizontal vibrations of the tone arm during the reproduction of a record disc and feeding back an output signal of the detector to the motors so as to cancel the vibrations, whereby high fidelity reproduction of sounds can be performed. Further, the stylus pressure adjustment and elevation angle adjustment of the tone arm are also performed.

Abstract: A phonograph record turntable assembly comprises a rotatable turntable having a rubber or other elastically flexible sheet overlying a substantial portion of its upper surface and secured thereto at least along an edge or edges of the sheet for defining at least one sealed interior space which contains a fluid material, preferably in the form of a viscous liquid, so as to provide a cushioned, vibration-damping record supporting surface which conforms to the shape of a warped or otherwise distorted phonograph record placed thereon. In order to avoid the accumulation of the liquid at any one portion of the interior space when the turntable is not horizontally disposed, such interior space may be divided into a plurality of liquid-containing compartments which are isolated from each other, as by partitions therebetween, and/or each interior space or compartment may further contain absorbent material which takes up the viscous liquid.

Abstract: A mat for a phonograph record turntable is made up of at least one rubber or other flexible enclosure defining at least one sealed interior space which contains a fluid material, preferably in the form of a viscous liquid, so as to provide a cushioned, vibration-damping record supporting surface which conforms to the shape of a warped or otherwise distorted phonograph record placed thereon. In order to avoid the accumulation of the liquid at any one portion of the mat when the turntable is not horizontally disposed, the interior of the mat may be divided into a plurality of liquid-containing spaces which are isolated from each other, as by partitions therebetween, and/or each interior space may further contain absorbent material which takes up the viscous liquid. The vibration-damping properties of the mat may be enhanced by providing solid particles which float in the viscous liquid.