Solar-Powered Outdoor Thermometer with Multiple DS18B20 Sensors

I’ve been pretty happy with how my ESP8266-powered outdoor thermometers turned out.  One of these has two sensors — one to measure ambient temperature, and one to measure the temperature of a hot tub.  It’s solar-powered (with an 18650 Li-Ion battery), uses a single GPIO pin, and never needs charging! DS18B20 Temperature Sensor DS18B20s* are […]