The low-cost unit is mounted in a balcony, away from potential local heat sources. The balcony is about 35-m above ground facing South. The unit is in the shade. The temperature included in this unit are: 2xDS18B20 (Maxim Integrated Products, Inc.), 1xSHT3x (Sensirion), DHT31, Si7021, BME280 (Bosch). The tutorial and a plan view of the sensors presented here. The data is read by an ESP8266 micro-controller and transmitted to a home server. In addition, a sample box with a Raspberry Pi has a shield with various sensors installed, including DS18B20, HDC1080, and MPL31152A. An AirVisual air quality monitor has a built-in temperature sensor. There is a comprehensive test on some of these sensors on the performance.
Forecasting sources were queried by open API including Darksky.net, OpenWeatherMap.org, UNIS School website on air quality. Lang station operated by Vietnam Meteorological and Hydrological Administration. Finally, a MERRA2 product is used the reanalysis data to compare against measured, forecast data. MERRA2 is produced by NASA targeting Earth system analysis with data dated back 1980.