Build Your Own Infrared Signal Recorder - Circuit Cellar
AIRWidget is a device that allows you to examine infrared signals from a remote control. You can see, save, analyze, and display what is being transmitted, with more accuracy than you’d get with a digital storage oscilloscope. In this article, I explain how an AIRWidget works and how to build one, so you can modify or add functions to any IR remote control device.
Source: circuitcellar.com