Abstract: In a radio communication apparatus, a counter is reset to its initial state if the user of the apparatus responds to an alert tone representative of call incoming, or caused to count the number of times of call incoming if the user does not respond. The number of times of call incoming occurred without any user's response and a reference value are compared. If the number of times counted and reference value compare equal, the volume of the alert tone is increased for the current call incoming or for the next call incoming. Further, If the user does not respond to the call incoming, a timer starts counting time. When call incoming is repeated within a preselected period of time, the volume of the alert tone is increased. Loudening the alert tone may be replaced with changing the pattern of the alert tone.