In this guide I will show you how to make your own Arduino digital thermometer by using the DHT-22 sensor and Arduino Pro Mini board. It can be powered up from any USB power source and it can report the max and min values for temperature and humidity as it works. In this guide you will also find the .stl files of the 3d printed case/box. The DHT-22 (also named as AM2302) is a digital-output relative humidity and temperature sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air, and spits out a digital signal on the data pin. The DHT22 is a basic, low-cost digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air, and spits out a digital signal on the data pin (no analog input pins needed).”

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