There is provided a radio apparatus usable in a frequency band of use comprising a feeder circuit, a first antenna element and a second antenna element. The cooling circuit includes a first cooling path through the compressor rotor in series with a second cooling path through the turbine rotor such that one amount of cooling air is used for cooling both the compressor rotor and the turbine rotor. The traffic monitor monitors the traffic of the network. The switching signal is responsive to the drive signal. Stored subscriber records allow the selection and periodicity of announcements to be customized.