Weak GPS Signal at Takeoff

harrisonmg · Sep 16, 2019

Hi,
Recently, my Mavic has been saying weak GPS signal when trying to take off at my house more and more. It says 4-7 sats, then when it hits 8 it lets me go more than 10ft-ish off the ground; but it keeps taking longer every time. Sometimes, I go out seeing a beautiful sky, launch the drone, and then have to wait 5 straight horrible minutes until I can fly, and the sun has gone down already. Is there something wrong, something I can do to fix this? It used to not be a problem a few months ago, then it was a few seconds, then a minute, then a few. I try keeping drone in place, moving around, walking around, it doesn't help.

Thanks!
Harrison

Meta4 · Sep 16, 2019

harrisonmg said:
Recently, my Mavic has been saying weak GPS signal when trying to take off at my house more and more. It says 4-7 sats, then when it hits 8 it lets me go more than 10ft-ish off the ground; but it keeps taking longer every time. Sometimes, I go out seeing a beautiful sky, launch the drone, and then have to wait 5 straight horrible minutes until I can fly, and the sun has gone down already. Is there something wrong, something I can do to fix this? It used to not be a problem a few months ago, then it was a few seconds, then a minute, then a few. I try keeping drone in place, moving around, walking around, it doesn't help.

The number of GPS sats your drone can acquire signals from will depend on how much of the sky is visible to it.
If you launch from a spot where the horizon and part of the sky is blocked by trees, buildings or terrain, the number of sats seen will be reduced.
Up higher where it gets a full horizon to horizon skyview, it will acquire the max number of sats.
What's the skyview like at your launch spot?
If you disable your VPS you will be able to fly much higher without sufficient sats at takeoff (but the drone will be in atti mode and subject to drifting until you do get enough sats for P-GPS mode.

harrisonmg · Sep 16, 2019

There is a house in one direction, big trees in all other three. That would explain it, there's really not all that much sky visible at take off.

This seems, though, a little backwards to me---it will let me move around laterally, but not vertically, where I could achieve a better signal just by going above the treetops.

I could do your recommendation; I just enable ATTI? What is that, turning off all sensors in the settings menu?

Thanks

Meta4 · Sep 16, 2019

harrisonmg said:
There is a house in one direction, big trees in all other three. That would explain it, there's really not all that much sky visible at take off.

That sounds about right.

harrisonmg said:
This seems, though, a little backwards to me---it will let me move around laterally, but not vertically, where I could achieve a better signal just by going above the treetops.
I could o your recommendation; I just enable ATTI? What is that, turning off all sensors in the settings menu?

You don't have to activate Atti Mode - that's what you are in if you don't have enough sats and the VPS is disabled.
How this affects the height you can climb to is explained on p56 of the manual:
Height is restricted to 16 ft (5 m) when the GPS signal is weak and Downward Vision System is activated. Height is restricted to 98 ft (30 m) when the GPS signal is weak and Downward Vision System is inactivated.

Otherwise it's a good idea to launch from somewhere that you do get a good skyview.

harrisonmg · Sep 16, 2019

Oh cool thanks for looking that information up for me lol.
I live in a place where it's a few minute ride to any large open space (significantly more so than my deck/backyard) so what I have will have to do.