Abstract: A simultaneous voice and data modem coordinates the storage of voice messages and data messages on an audio answering machine and a personal computer, respectively. This allows the called party to subsequently retrieve, via the simultaneous voice and data modem, both a voice message and an associated data message, i.e., a multimedia message, where the called party listens to the voice message while viewing the data message. The called party can retrieve the multimedia message either locally or from a remote location.

Abstract: A correction circuit for use with a subscriber line interface circuit (SLIC) to control the level of a DC voltage supplied to the tip and ring wires of a telephone circuit includes a current sink with a differential operational amplifier. The amplifier output terminal is connected through an output resistor to a control input of the SLIC which influences the DC voltage level. The non-inverting input terminal of the amplifier is connected to the tip or ring wire, or both, and the inverting input terminal is connected to the output resistor and a DC reference circuit. The level of the voltage supplied by the SLIC is a function of the current supplied by the correction circuit.