The present invention relates to a procedure for using a radio phone (2) with an external amplifying device (1) for receiving, amplifying and transmitting a radio frequency reception signal to the radio phone, in which radio phone a reception frequency signal is supplied to a front end amplifier (9). When the external amplifying device (1) is connected to the radio phone, the front end amplifier (9) of the radio phone is bypassed or the gain thereof (9) is adjusted to be lower. The control signal (OHJ) is preferably a voltage control signal of direct voltage frequency or low frequency produced in the amplifying device (1), which in the amplifying device is added into the reception signal, and in the radio phone separated from the reception signal into a control :signal of the front end amplifier.