Abstract: A device for the storage and playback of audio signals originating from at least one portable medium includes a player for reading audio information from a portable medium having a plurality of audio tracks. The player transmits an audio output signal corresponding to a selected audio track. A storage device operatively connects to the player for receiving the output signal and storing the plurality of audio tracks. The device further includes a user interface control panel. A controller is adapted to receive user input from the control panel regarding desired playback of a selected track and records the playback information of the selected track in memory to prioritize the tracks relative to one another. The controller is further adapted to receive user input to control the player and the storage device to play at least portions of the stored plurality of audio tracks such that playing of the tracks is dependant on the playback information.

Abstract: A microprocessor samples the net effective current from a battery several times a second. A fast average current I.sub.f is calculated using an IIR filter on the net average current. A slow average current I is calculated by integrating the net average current over time with respect to time. An Ampere Hour Capacity is calculated by the use of the Peukert equation, which is split into two terms. A first capacity term is calculated using the fast average current I.sub.f and a slow capacity term is calculated using the slow average current I. The slow capacity term is then multiplied by a weighting constant C.sub.2 and summed with the fast capacity term which is multiplied by (1-C.sub.2).