Go4App question - directional compass

gtoddjames · Apr 28, 2018

MP Q - on the 'radar dial' in the lower-left of the Go4 screen, the red arrow is craft orientation .. that's easy.. (N) is north .. and the white diamond is 'controller direction' (CD)... got all that. My question is: "Shouldn't the (N) always stay pointing north and the CD move as the controller changes orientation/direction?" (And obviously the craft orientation arrow should reflect the direction of the craft itself.) The reason I ask is (1) my craft orientation arrow is off by 90-180 degrees from 'actual craft direction'... (2) (N) is 'fixed' to the difference to craft orientation - in other words, let's say the craft arrow points at 360/0 degrees and (N) is at 315 (45 degrees left of craft orientation) - if the craft turns left to heading 270, (N) precedes it to 225 degrees... (3) the controller orientation arrow never moves. Period. DJI had me send it in today for a 'compass chip' replacement. Would you agree with the preliminary diagnosis or could it be something else? Oh, the very last flight had a lot of Ocusync/video jutter and skip.. almost like a signaling interference but it was a known/'safe' field... Maybe related, maybe not.

Paul2660 · Apr 28, 2018

Mine does this also at times. IPad iOS 11

Sometimes it’s perfect north is up and red arrow is pointing to direction of travel. But about 1/3 is the time when I first start up the display has N pointing to the left which makes it harder to follow. Over in the right side in the map it’s always correct.

On the map you can hit the small compass to orient up or direction of travel. I have never figured out a way to fix the compass display when it loads in with the north pointing to the left not up.

Paul Caldwell

Dragonfly · Apr 28, 2018

The White N and outside arrows only work if you have a built in compass on the device you are using as it reflects the directions you(the RC/phone) is facing in relation to compass and drone position.

atxmavic · Apr 30, 2018

Paul2660 said:
Mine does this also at times. IPad iOS 11

Sometimes it’s perfect north is up and red arrow is pointing to direction of travel. But about 1/3 is the time when I first start up the display has N pointing to the left which makes it harder to follow. Over in the right side in the map it’s always correct.

On the map you can hit the small compass to orient up or direction of travel. I have never figured out a way to fix the compass display when it loads in with the north pointing to the left not up.

Paul Caldwell

Paul - are you using an iPad Air 2 or some other model? I'm finding that the Air2 has a much stronger internal magnet than the (2017) iPad ... strong enough to pull a needle compass up to 180 degrees... Yes, logically this could be part of my problem BUT it does not explain why it has the same behavior on an Android Smartphone or the random needle-flipping even when distant to the craft or RC.

The radar screen works right for about the first 10 seconds in this video then you know where it goes... Anything after the first minute or two is just "more of the same".

gtoddjames · May 2, 2018

Ok - just got word back today that DJI is replacing the compass board and GPS module under warranty - it should be home sometime next week. One thing I did learn was that the Air2 (at least mine does) has a much stronger internal magnet/battery/something than a typical (2017) iPad - enough to spin a 'needle compass' 180 degrees... Even though this combination is supported by DJI, I have to wonder if I am not alone with this .... weirdness. Anyway, two more things learned - (1) both the Air2 and the iPad have internal compasses - not GPS but they have magnetic compasses (What You Need to Know About iPad Air 2 and iPad Mini 3 GPS) which you can easily confirm by downloading a compass app and comparing it to your phone/needle compass almost anywhere - it may not be exact but it's close enough for government work; (2) there are no YouTubes on how the 'radar screen' SHOULD behave right "out of the box" - maybe I'll make one... I stand by my belief that the "N" should always point north regardless of craft (arrow) direction and that the white diamond (RC direction) should rotate around the circle as the RC moves... We'll see when it gets back.

Porto · May 2, 2018

I usually have no compass direction problem when using ios Go4. But when using android Go4, I have to recalibrate the device (phone/tablet) compass while in Go4 everytime before flying. Once the device is recalibrated (several figure 8 movements), "N" will always points to North. As long as I don't close Go4, I can change battery and fly again without having to recalibrate.