I'm new to posting on the forums but have been reading your posts for a couple years now, thank you for all the great discussions and advice over the years.
I'd love to share with you all a project we've been working on, it's a low cost tethered power system that can replace the battery on any small size quad or hex. We've been testing it on a DJI F450 and the F550 flamewheels so far and it should work on the Phantom 1 or 2 (not yet the 3, as they encrypt the battery signals but we're working on it). Basically we wanted to be able to do long time-lapse videos and just get a fixed bird's eye view on things without having to swap batteries every 20 mins.
The system is in 3 parts that all pack into a small briefcase:
1. The power box on the ground, which takes any of the usual power options; mains supply, car battery (deep cycle) or generator etc... and turns it into a high voltage output.
2. The high voltage cable, in order to keep it's weight to a minimum.
3. Finally the transformer system in the air which takes the high voltage and drops it down into the 15V for the motors. This is approximately the size of a 5000mah battery pack.
So far we've tested it to 50m with a gopro onboard, but it used much less power than we thought it might so it should be able to reach 100m. Slight delay now as we're just sourcing a more suitable cable as this one tangles really easily.
Anyway I'd love to know your thoughts, I know a tethered system isn't for every application, it's horses for courses. But if you're in the UK and want to have a play with it, do let me know. We're wondering about putting it on kickstarter... not sure, all comments welcome.
We've got some more photos etc... on our instagram page. https://www.instagram.com/unmnd/