TELEPHONE DEVICE MOUNTED IN VEHICLE

摘要

A telephone device has a connection wiring section (21b) for connecting an external power supply parallel with an internal power supply, a switch (22) for controlling the supply of electric power to the telephone device from the parallel connected external and internal power supplies, and a control circuit (12) for controlling the switch (22) so as to supply electric power to the telephone device if as ignition switch is detected to be on or if the user is using the telephone device. Even if the ignition switch is turned off while the user is using the telephone device sad resultantly the supply of electric power from the external power supply is stopped, the telephone device can operate by means of the internal power supply to continue the use of the telephone device. Further the telephone device has a speaker (4) for generating a key-click sound provided in a receiving section, setting means (12) for setting the volume of the key-click sound generated from the speaker, and control means (12) for adjusting the volume of the sound to a predetermined level or less if the telephone device is used or to the value preset by the setting means if not used. Hence no large click sound is generated while the telephone device is used.