Digital cameras can detect infra-red light but our eyes can't. Use a digital camera, webcam or camcorder and look through the digital viewfinder at the IR LEDs, after pressing the button, the LEDs should flash.
Some modern Apple cameras have IR filters, so you may not see the purple light! Try another camera or skip this step!
This guide was first published on Apr 21, 2013. It was last updated on Apr 21, 2013.
This page (Test it!) was last updated on Oct 26, 2020.