Hi all -

I've been goofing around with my new Phantom 3 SE for a few weeks now. I've read the manual and have slowly been increasing height and distance limits as I become more comfortable with it. I have 2 questions:

1) I live on a pretty steeply sloped property. It slopes upward from front to back and is wooded. If I take off from the front and over the house, I'll lose signal about 400 feet away. It will return to home by itself and the controller will reconnect once inside that ~400 foot distance. If I launch from the front and go straight out, the ground drops away from me and I have not yet had a signal issue in that direction. Is the lesson here that terrain has a pretty dramatic impact on signal range?

2) This behavior started yesterday. Without warning, the drone will start rapidly "scanning" from right to left, left to right. Quickly and sharply. When this happens I bring it down quickly for fear of some other malfunction. As I do this, the behavior continues and the quick descent causes it to wobble pretty significantly - so much that the gimbal can't correct for it. It doesn't do it every time, but it's done it on 2 out of 5 flights in the past 24 hours. Could it be some sort of radio interference? Altitude and distance do not seem to be a factor - it's completely random.

Thanks!

1)  You have to be sure you're aiming correctly.  But yes, slope of the terrain can have a dramatic effect on signal quality depending on high off the ground the AC is flying.  Study Fresnel Zone for more details.

2)  You mentioned lots of trees.  Be sure you have full GPS. and it's not switching to ATTI.  Otherwise it sounds like an IMU issue (calibration needed).  

Line of sight also is significant for signal from the transmitter as well. If hill, trees, or building blocks your line of sight, then it will block your transmitter signal as well.  Signal may penetrate trees without leaves for a while until density/distance intervene. Think of LOS as line of signal as well as line of sight.

Find a relativity flat, open area to fly in and see if these things still happen.

Thanks all for the replies. I was able to duplicate the signal loss flying in the other direction, too. This time it was 1,000 feet away. So that's pretty much confirmation that the terrain plays a pretty big role. Uphill I lose it at 400 feet, downhill I lose it at 1,000 feet.  I guess it is the trees. I'm literally surrounded by them. I need to get the drone up above them in order to travel any sort of distance. I hadn't realized the importance of LOS.  I'll find a wide open spot and see if that improves things. I take off and land from the yellow dot in the pic:

If you can,then go to the highest place on that area and start your Phantom there to get a distance more than 1000 feet without signal loss. The interferences can be there from any WIFI network in these houses. Trees can disturb both video and control signals as the GPS signal too.

You could be getting interference from the houses as well.

Is the yellow dot your house?  I would pilot from the top of that fairway and fly straight towards the camera except lower and further.  Always check wind before flight.  

Yes, the yellow dot is my house. I get the best distance doing exactly what you said - flying from there straight out. Sill, I lost signal at 1,000 feet. I'll experiment with different launch points.

Try standing with the driveway behind you - see if that helps

turbojimmy Posted at 2017-12-3 12:20
Thanks all for the replies. I was able to duplicate the signal loss flying in the other direction, too. This time it was 1,000 feet away. So that's pretty much confirmation that the terrain plays a pretty big role. Uphill I lose it at 400 feet, downhill I lose it at 1,000 feet.  I guess it is the trees. I'm literally surrounded by them. I need to get the drone up above them in order to travel any sort of distance. I hadn't realized the importance of LOS.  I'll find a wide open spot and see if that improves things. I take off and land from the yellow dot in the pic: [view_image]

So that's pretty much confirmation that the terrain plays a pretty big role.
If you have a clear, unobstructed line of sight to your Phantom, terrain has no effect on signal.
Look for other factors that might be at play.

Hey Jimmy, the above discussion make sense. The signal might be shielded by the terrain. As for the second question, make sure there are good GPS signal and test the performance in an open outdoor location, take care!