The general idea here is that you'd use the fast-forward and fast-reverse keys to move around quickly until you see the device power on or off, and then use the stepwise keys to find out exactly which keyset triggered the power switch. There are caveats here, of course: quite a number of devices don't have a remote "power" key, so this mechanism won't catch them. Also, some manufacturers make really strange decisions about their key values: for example, as I've just discovered, the "Power" button for the Sanyo TV Keyset 1a is exactly the same as the "Factory Reset" button in Sanyo TV Keyset 1. (Luckily, you have to hit the reset button twice to perform the reset, so I didn't lose all my TV settings. I have no idea what the engineers at Sanyo were thinking...) So be warned, even just looking for power buttons can be dangerous!