If you look at the back of an Apple TV you will notice that it takes mains power. Most days I'd be happy about this because it means one less power brick; but today, not so much. The thing about flying a drone is that there's not usually mains electric to be had. So the Apple TV needs to run off a battery.

Fortunately this problem has been solved before by people who own boats. This excellent blog post (http://i-marineapps.blogspot.com/2014/04/appletv-5-volt-usb-conversion.html) gives all the details of how to convert your Apple TV from mains power to one taking a battery. As they point out in the article, the hardest part of the whole conversion is getting the damn case open!

This is what my modded Apple TV looks like. I used a 5.5mm power connector to feed the DC-to-DC converted because it was the same size as the power connectors on the goggles.