GPS

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Hello, I'm a newb. I just purchased the Standard and notice that, at times, I have difficult getting the desired 7 channels to attain GPS lock. I launch from the same spot...back deck of the house in a semi-rural area. It goes from 2 to 6 and then hits 7 and 8 and back down again. Should I re-calibrate the compass?

Thanks,

Joe
 
Hello, I'm a newb. I just purchased the Standard and notice that, at times, I have difficult getting the desired 7 channels to attain GPS lock. I launch from the same spot...back deck of the house in a semi-rural area. It goes from 2 to 6 and then hits 7 and 8 and back down again. Should I re-calibrate the compass?
Doing anything to the compass will have mo effect on your GPS and how it receives satellite signals.
Having a clear view of the sky will help you receive the maximum number of satellites.
How much of the sky is blocked from your launch point?
 
GPS and compass are separate (but related) subsystems.
GPS coverage depends on a clear line of sight to as much sky as possible from the top of the Phantom. It also depends on how many sats are currently visible, which varies.
Back deck of a house may mean that the house is obscuring half of the sky - also, depending on how big your deck is and what it's made from, could cause poor compass calibration.
 
Doesn't seem like it's blocked, but I am launching from my deck, right next to my house and it is possible that top of phantom doesn't see all satellites...Thanks!

Sent from my SM-G900V using PhantomPilots mobile app
 
it also depends from what you are launching. There are lots of materials I have found that screw up the Phantoms gps and compass so I have done lots of hand launches lately as a result.

Concrete seems to be pretty bad but sometimes even something like a picnic table will keep it from getting to P mode
 
Yea, the antenna has about a 180 degree aperture and there is a 5 degree or so mask to ignore SVs near the horizon so you need to be clear of tall objects nearby.
 
The misconception of non-relation of Compass with GPS is common.

The two are complimentary to each other. Why ?

GPS provides positional data but has no idea of direction. It needs Compass data to work to have aircraft do such as RTH etc.

As others say - clear line of sight to sky is needed to get good sat lock. The number of sats needed for 3D position is actually 4 sats minimum with general navigation units. (My profession was Professional navigator before present).
Depending on application - the number of sats required can be altered in software ... DJI appear to have increased the number required.

DJI themselves advise that if Compass error is found - to RISE in altitude for GPS to lock in better and clean data to be made to the IMU and Compass ... > Page 58 ....
 
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