PORTABLE INFORMATION TERMINAL

摘要

PROBLEM TO BE SOLVED: To improve the convenience for a public radio telephone communication by providing a wireless earphone microphone and to extend the battery service life by controlling the use of the wireless earphone microphone, depending on a battery voltage. SOLUTION: In a portable information terminal provided with a main body 1 and a voice speech use wireless earphone microphone 2, a voltage discriminating section 130 compares the output of a voltage detection section 14 which detects a voltage of a battery 3 with a prescribed voltage and a power supply control section 131 activates/inactivates a power supply of a transceiver section 12, depending on the result of comparison to select automatically whether or not the wireless earphone microphone 2 is in use thereby, thus extending the service life of the battery 3.