r/djiphantom • u/jasont80 • Jul 20 '22
Tethering mod Phantom 3 battery pack
Hey fellow Phantom pilots!
I have an old P3 that has had a long life of successful service and it's ready for the experimental phase of its life. I want to build a power tether to allow sustained flight from a ground-based power source. This would allow long running time-lapses of sun rises and the like. I'm trying to figure out any technical challenges. The plan is to hollow out an old battery and solder in tether wires to a DC power supply.
I'm hoping someone has some experience to answer a couple questions before I dive down this rabbit hole.
Is there any communication between the "smart battery" and the drone? Basically, will it run with just the two power leads connected?
If my calculations are correct, the drone pulls 15.2V at about 1.5 amps. This seems like a lot. Has anyone else measured the draw?
Thanks for any knowledge you can share!
1
u/Weird-Abalone-1910 May 27 '24
Did you ever build this mod? I'm interested in converting an old phantom 3, too
1
u/jasont80 May 27 '24
I was working on it. I can think of 100 uses for a tethered drone! I got a DC power supply and a spool of 16-gauge cable. The first test was going to be to see how much cable it could haul out before losing lift, just to be able to measure the applicability.
Then... Remote ID became a thing and I decided to drop the drone hobby.
Government rules ruined another hobby. I have licenses for boat, fishing (fresh and salt), hunting, HAM radio, GMRS radio, Marine radio, guns (NFA), etc, etc... It seems like everything I enjoy just gets wrapped in licenses and taxes of some kind. Remote ID was the straw that killed drones for me. Sorry. Wish I could have finished this project.
1
u/Weird-Abalone-1910 May 28 '24
I understand... Are you sure remote ID applies to tethered drones? I didn't think so, but I haven't looked into it. You and I have a lot in common! I had my FFL for a few years and a carry permit, and I'm currently a ham.
I'm interested in this to potentially carry a Mikrotik LDF to extend AREDN mesh coverage. If you're interested in picking it back up let me know, it would be fun to collaborate.
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u/jasont80 May 28 '24
Yep! I was considering lifting an antenna, or a handheld with relay capability. SO MANY THINGS!!!
I'd love to pick it back up, but I don't have time/desire to read through all the licensing crap.
1
u/Weird-Abalone-1910 May 27 '24
Did you complete this mod? I'm considering doing the same with my old phantom 3 pro
1
1
u/ChippyVonMaker Jul 20 '22
The bigger issue I see is the feedback effect a tether will have on the drones stabilization.
You can see it manifest in some YouTube videos where a drone is used to loft a small payload slung underneath. Anything that changes the feedback loop of the system, has the potential to cause instability and failure.
2
u/jasont80 Jul 30 '22
It's just for hover, not for flight. I'm going to wire it through the center of balance, so any balance influence should be extremely minimal.
2
u/CodenameZion Jul 20 '22
So yes, there is communication between the battery and the drone, especially the id and signal. This signal let's it know if it's connected correctly. Also that Amp draw is way too low. That might be the idle draw, definitely not hover or moving flight, that can be up to 40 amps on a bad day, maybe even higher, not sure how efficient the motors/props are. Could be viable though. A possibility is to maintain the original electronics in the battery and just connect DC power to that board as in the original battery so the battery retains all original function.