a portable telecommunications device has a radio transceiver , a keypad , a memory , and a microcontroller for controlling device functions . the portable telecommunications device receives an incoming call from a calling party that calls a called party who is operating the portable telecommunications device . upon receiving the incoming call , the portable telecommunications device alerts the called party . when the called party presses a key other than the hook key , the portable telecommunications device starts periodic transmission of a waiting message to the calling party while putting the portable telecommunications device on hold . the portable telecommunications device halts the periodic transmission of waiting messages and returns to normal communication mode when the called party initiates such halting .