a radio apparatus , in particular for mobile radio , of a first predetermined power stage is proposed , whose broadcasting power can be increased by connecting a hf amplifier circuit . the radio apparatus has an antenna output , to which an input of a hf amplifier circuit can be connected , for operating the radio apparatus at a higher , second power stage . as a function of the hf amplifier circuit connected to the radio apparatus , a transmitter unit of the radio apparatus outputs signals for transmission to a radio network , which signals contain the information about operation at the applicable power stage .