Abstract: Approaches for inducing a magnetic bias in a magnetic recording disk. A biasing apparatus comprises a soft magnetic material member having a shape comprising two opposing recesses, denoted an upper recess and a lower recess. A first magnet is disposed within the upper recess and a second magnet disposed within the lower recess. An air gap exists between the first magnet and the second magnet. An opening in the soft magnetic material member is sized to accommodate at least a portion of the magnetic recording disk between the first magnet and the second magnet. The magnetic field produced by both the first magnetic and the second magnetic flows (a) in the same direction, and (b) perpendicular to the plane of the magnetic recording disk. Using this approach, magnetic material on the disk, such as magnetic islands of a bit pattern media, may be erased and polarized in the same direction.

Abstract: Approaches for inducing a magnetic bias in a magnetic recording disk. A biasing apparatus comprises a soft magnetic material member having a shape comprising two opposing recesses, denoted an upper recess and a lower recess. A first magnet is disposed within the upper recess and a second magnet disposed within the lower recess. An air gap exists between the first magnet and the second magnet. An opening in the soft magnetic material member is sized to accommodate at least a portion of the magnetic recording disk between the first magnet and the second magnet. The magnetic field produced by both the first magnetic and the second magnetic flows (a) in the same direction, and (b) perpendicular to the plane of the magnetic recording disk. Using this approach, magnetic material on the disk, such as magnetic islands of a bit pattern media, may be erased and polarized in the same direction.

Abstract: A musical instrument is disclosed which is constructed of a group of taut strings arranged to be strummed, each string being connected to operate an analog switch capable of producing a graduated signal that is directly proportional to the amplitude of vibration of its string, an extrinsic sound source in circuit with each analog switch, the sound source having a variable volume which is varied directly proportional to the strength of the signal from the analog switch, a number of switch means arranged in a keyboard, each of which may close the circuit to one or more preselected sound sources for which the switch means are closed and the strings are vibrating.