Abstract: An apparatus for use in the activity of freediving, providing the freediver with increased safety and protection in the event of Shallow Water Blackout, incapacitating hypoxia, or other emergency occurring in or under the water, while providing greater reliability of functioning, and comfort of wearing during the activity of freediving.

Abstract: An apparatus for use in the activity of freediving, providing the freediver with increased safety and protection in the event of Shallow Water Blackout, incapacitating hypoxia, or other emergency occurring in or under the water, while providing greater reliability of functioning, and comfort of wearing during the activity of freediving.

Abstract: A multi-channel sound simulation system for processing a stereophonic signal having a high frequency component for use with at least a pair of primary loudspeakers and a pair of secondary loudspeakers includes a receiving member for receiving the stereophonic signal and for producing a first primary channel signal and a second primary channel signal. The first and second primary channel signals are adapted to be respectively applied to a first primary loudspeaker and a second primary loudspeaker. The receiving member is further adapted to divide the input signal into a first secondary channel signal and a second secondary channel signal. The first and second secondary channel signals are fed through a roll-off member which inhibits the high frequency component of the signal, thereby producing inhibited first and second secondary channel signals.

Abstract: The invention provides a method and apparatus for rapid and accurate stylus overhang positioning and tangential alignment with respect to a turntable. Accordingly a stylus locater plate having an aperture and a stylus positioning mark spaced therefrom is mounted on the spindle of a turntable. A pivot arm is connected to the locater plate on the other side of said spindle from the stylus positioning mark. The pivot arm and thus the locater plate, are then rotated around the spindle until such arm crosses over the pivot axis of the stylus arm of the turntable, to locate the mark in the turntable. The stylus arm is then pivoted toward the mark and the stylus cartridge is adjusted in the stylus arm to position the stylus in registration with such mark.The locater plate is further provided with lines near such mark to guide the angular positioning of the stylus cartridge into a tangential alignment with the record grooves at such mark.