DataLogger based on Arduino with 434MHz radio and BME280 sensor supplied by 3.6V battery for the transmitter and RaspberryPiZeroW & CC1101 with Python program for receiver.
Temperature, pressure and humidity in Weyher in der Pfalz, Germany. Solar powered Wemos with BME280 connected to public Wifi "Freifunk Weyher"
Raspberry + Thunderboard sense with temperature, humidity, VOC and eCO2