Show All ItemsDo you get sick of your cheap piece of crap AC unit making things too cold, like I do?--but when you turn it off, the room gets too hot; dumb thing doesn't have a decent thermostat.In this tutorial I will show you how to make a device that automatically regulates temperature, or that activates a device when the temperature reaches a certain point. This could be any device, but for example, I will be using an air conditioner in an upstairs bedroom. Step 1: Gathering supplies Show All ItemsFirst things first. You will need some parts to get this project going, so head to your favorite electronics website and purchase the following:1. Arduino--Doesn't need to be an Uno, but if you use a different board, some of the pins may change; I will cover that later.2. Cheap arduino-compatible relay module--almost any type will work.3. DS18B20 Temperature Sensor--A cheap ebay version will work just fine!4. 96" i2C 128X64 OLED display (optional)--Make sure it is i2C and not SPI serial// Not used -->> 6.C945 NPN transistor (Depending on the relay module used)