摘要:
There is described, among other things, an accessory for a phonograph record disc which has a center hole axially of label portion of the disc. The accessory comprises a sheet which is of circular annular shape and has a diameter not substantially greater than the disc label portion. One side of the sheet carries adhesive for affixing the sheet to the label portion of the record concentric to its center hole. The opposite side of the sheet carries an annular band which is positioned concentric to the center of the sheet. The annular band is defined by a magnetic recording medium. The magnetic recording medium facilitates the placement of information on the record disc which can be read and used by a programmable record player.The invention also describes a phonograph record having a central label portion and a circular hole through its axis. The record includes a band of magnetic recording medium affixed to the label portion concentric to the hole.
摘要:
Method and apparatus for obtaining a measure of or relating to lateral tracking error at each of a plurality of predetermined radial distances from the spindle axis of phonographic turntable equipment that includes a spindle (13), a rotatable platter (14), and a pivotally mounted tonearm (11) to carry a cartridge-mounted stylus (12) via a separate or integral headshell (16). The apparatus comprises an alignment protractor (20, 120) placed on the platter for arcuate movement about the spindle axis, and a device (30, 130, 40) mounted on the tonearm in place of the cartridge or both the cartridge and headshell. The alignment protractor (20) is marked with a plurality of equi-angularly spaced radial lines indicative of differing tracking error values and a plurality of equi-spaced transverse straight lines crossing all the radial lines and intersecting at right angles the radial line indicative of zero tracking error. The device (30, 40) is marked with a distance scale comprising a main line (35, 45) directed at the offset angle with respect to the tonearm and intersected by equi-spaced distance marks corresponding to and/or defining different stylus points (whereby each distance mark defines a different value for the stylus overhang distance).
摘要:
Audio playback apparatus is disclosed including a tone arm which is positioned electromagnetically to facilitate control thereof in accordance with the position of a turntable relative to the tone arm. The apparatus is particularly suited for random access retrieval of audio information from a record including a plurality of nested spirals each corresponding to items of information on a display or selection chart. An array of switches corresponding to individual items on the display and a position selector switch assembly operated by the position of the turntable relative to the tone arm cooperate to position the stylus of the tone arm in a spiral groove corresponding to the selected portion of the display.