Aspects are disclosed for positioning an access point base station. The circuit arrangement is suitable for operation in a wireless network, in which the higher or the lower of two frequency ranges defined in one frequency band is used selectively for transmitting and the other frequency range is used for receiving the wireless signals within the one frequency band. When material of small particle diameter clogs the crushing space and stays therein, the cutting teeth cut the material to form a gap. The system further calculates unit costs for the product. A membrane is attached to the intermediate member to cover an opening of the cavity, and to allow pressure from outside to propagate into a pressure transmitting medium contained inside the housing and thus to the pressure sensing arrangement therein.