B+B Thermo-Technik's radio system for transmitting temperature data operates in smalllow-energy radio networks, according to IEEE 802.15.4 within the licence free 2.4GHz band. One network may operate up to 15 sending units and one repeater. Multiple networks may operate parallel at the same time. Maximum operating range is up to 300m in an open area with an external mounted antenna and 50m in buildings. Four freely programmable analogue outputs enable an analyzing of the radio signal.