Wireless standards such as Sigfox and LoRa are available whenever battery-powered sensors need to transmit data to an Internet gateway. Sigfox scores high with a uniform and well-developed network. All the user must do is program and log on the sensor nodes in order to visualize their output data on the Internet. As we show in this series, cost-effective hardware and free software are enough to realize the first Sigfox projects. In the first part we present the compact Arduino MKR FOX 1200 module with an integrated Sigfox transceiver and a corresponding motherboard.