Cheaper sense and sensor-abilities

The ever-frugal Les Pounder reveals how two of the cheapest sensors on the market can bring a wealth of data to your Raspberry Pi project.

- Les Pounder

The DS18B20 and DHT11 are two cheap, simple-to-use temperature sensors. They can even work side-by-side for added data collection.

OUR EXPERT

Les Pounder is the under-paid associate editor at Tom's Hardware and a freelance maker for hire.

YOU NEED

> Any Pi model

> The latest Pi OS

> DHT11 temperature sensor

> 3x female to female jumper wires

> DS18B20 temperature sensor

> 4.7K Ohm resistor (Yellow Purple Red Gold)

> Breadboard

> 3x male to female jumper wire

> Code and diagrams at https://bit.ly/Ixf290sensors

The electronics world has many different, cheap and simple sensors that we can use to gather temperature data. We've chosen two models that meet all of those categories, and will show you how to use them with just a few lines of Python.

Three wires is all we need to connect the DHT11 to our Raspberry Pi. Buy a DHT11 with a built-in resistor - they're much easier to work with.

Project 1: DHT11 sensor

The DHT11 is often bundled in electronics kits for the Raspberry Pi and Arduino. It's accurate to within five per cent between 20 and 80 per cent humidity, and ±2°C between 0 and 50°C. This makes it a great hobby sensor, but not ideal for projects that require precision.

There are two versions of the DHT11: a basic version with no pull-up resistor; and our version, which has an integrated resistor. If you can, buy this version.