CAR AUDIO DEVICE PREPARED WITH TELEPHONE MODE CONVERSION FUNCTION

摘要

PURPOSE: A car audio prepared with a telephone mode conversion function is provided to easily select a telephone mode and to easily regulate the volume of a telephone receiving signal by installing a telephone mode selection switch around a drive seat. CONSTITUTION: In connecting a car audio device to a mobile phone through an ear phone jack(8a), a driver selects a telephone mode selection switch installed in a control panel of the car audio. The mobile phone(8) is operated to a telephone call mode by the selection of the telephone mode. Thereby, the driver selects easily by installing the telephone mode selection switch near a drive seat. A PNP typed switching transistor is turned on by the selection so that a high level output to a KOS port is entered into a KS1 port. A microcomputer(20) recognizes the entry of the high level and controls for a volume regulation unit(24) to select a telephone receiving signal. The telephone receiving signal is amplified in a signal amplification unit(23). Thereby, the counterpart's voice received in the mobile phone is listened through a speaker.