Even if you aren’t looking to make your own makeshift alarm system, the code and video after the break are a great example to follow if you want to get started with 433 MHz hardware ...

He’s using an Arduino Uno and an Ethernet ... to send text messages to himself when the alarm system is armed, disarmed, or triggered. All the code is available on GitHub in case you also ...

Linking the Arduino to another device, such as a speaker, will allow you to set up a chime that will trigger if the door is rattled. If your security system works with third-party accessories ...