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This device uses radio technologies to communicate with the environment. Mainly the internal antenna causes a good RF performance. However, the RF performance will degrade by a faulty application. In addition to a minimum distance of 20 cm to the human body, you should avoid larger metal surfaces in the device's immediate vicinity. Placing the device on such a surface could negatively affect the transmitting and receiving power and changes the radiation pattern. Even humidity will cause an attenuating effect. Use the device in free space for optimal conditions regarding the RF performance.
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