I got my P3 standard about 3 months ago and have had constant "Disconnect" and poor FPV video problems. I am using the DJI OEM RC and antenna. It did not matter if I was at home or out in an open field. I recently discovered that if I removed my tablet from the RC mount the issues improved dramatically and pretty much went away. So I took a piece of Aluminum foil and placed it along the back side of my tablet and mounted to my RC. My "Disconnect" issue occurs much less and my FPV video is clear when connected at home. Still need to check in the field.  I left about ~.5 inch of my phone exposed along the top backside to help with GPS reception. I also wrapped the aluminum foil along the bottom edge of my tablet. I am trying to find someone with the same issue to see if they can get the same results. The results are almost to good to believe. It appears there was an interference issue between my tablet and the RC.
You cannot see the aluminum foil in the pictures because it is behind duct tape.
Samsung Galaxy A - 8 inch tablet.


Works with both DJI go and Litchi apps.
Current firmware installed.

Second picture that did not upload the first time.

Second picture is failing to upload.

Has that tablet got ventilation slots or holes?  Wouldn't want to block any cooling.

No slots or holes. Over heating is not a problem so far, but it is still cool out. I would attach another pic but I can't figure out how to attach.

fans6d6a663b Posted at 2017-3-31 16:03
No slots or holes. Over heating is not a problem so far, but it is still cool out. I would attach another pic but I can't figure out how to attach.

The "picture" icon in the "reply" box doesn't work for local (on your hard drive) images. It requires a URL.

To post a local image from the reply box, click "advanced" (brings up a different window) and then click "attachment" (paper clip icon).

Now that said, I really don't understand what you're doing.

Wrapping a shield around your display because of poor connectivity sounds a bit like painting your windows black because you can't see outside.

John Smith Posted at 2017-3-31 23:24
The "picture" icon in the "reply" box doesn't work for local (on your hard drive) images. It requires a URL.

To post a local image from the reply box, click "advanced" (brings up a different window) and then click "attachment" (paper clip icon).

The Aluminum foil is between the tablet and the RC, not over the display.

Phone in holder with AL foil backing

fans6d6a663b Posted at 2017-4-1 01:39
The Aluminum foil is between the tablet and the RC, not over the display.

Right. I kind of figured that.

Let's try it this way:

Putting a shield between your tablet and your rc because of poor connectivity sounds a bit like painting your windows black because you can't see outside.

I've a feeling you think the drone is streaming to your display unit, and that the rc is somehow interfering with that signal, but that's not right.

The drone is streaming to your rc which then transfers it to your display device, so I don't see how putting a shield between them could improve your fpv.

Note that your display unit uses its wifi to connect to the rc, not the ac.

John, Thanks for the reply. I'm thinking radiated noise created in the phone is corrupting the video signal to the RC. All I can say right now is that my constant disconnecting went away and the FPV video displayed on my tablet is cleaner, meaning less stutter and flickering. I do need more data to prove this. That is why I was hoping someone else seeing the same issues could try.

JoeO Posted at 2017-4-1 03:25
John, Thanks for the reply. I'm thinking radiated noise created in the phone is corrupting the video signal to the RC. All I can say right now is that my constant disconnecting went away and the FPV video displayed on my tablet is cleaner, meaning less stutter and flickering. I do need more data to prove this. That is why I was hoping someone else seeing the same issues could try.

bty...I updated my username to JoeO.

I see.  So this is somewhat similar to the GPS cable mod we used to do with the P2 series.  That is, we would re-route the GPS cable in the AC so most of it is behind the layered foil shield - thereby protecting it from radiation from the AC hardware - and this would give us more satellites.  

Thing is, you don't want to block the antenna inside the tablet from receiving the wifi signal from the controller.  But otherwise it makes sense.  Maybe the controller is so close to the tablet that it doesn't matter.

I'm going to try this!  Thank you!

Mark The Droner Posted at 2017-4-1 04:16
I see.  So this is somewhat similar to the GPS cable mod we used to do with the P2 series.  That is, we would re-route the GPS cable so most of it is behind the layered foil shield - thereby protecting it from radiation from the AC hardware - and this would give us more satellites.  

Thing is, you don't want to block the antenna inside the tablet from receiving the wifi signal from the controller.  But otherwise it makes sense.  

The aluminum foil did appear to degrade GPS on my tablet slightly, but not to the point of losing my location on the map. I determined this using a free Android app called "GPS Test" which displays satellite SNR. GPS reception is why I left about 3/4 inch of the tablet top backside free of aluminum foil.

Ahh okay.  That's also where the wifi antenna is on my Nvidia tablet - right along the top edge.  

https://d3nevzfk7ii3be.cloudfront.net/igi/5GB3FM6FwqFojhp5.medium

I will do the same.  

Too windy to fly today...

JoeO Posted at 2017-4-1 03:38
bty...I updated my username to JoeO.

A vast improvement...  

Anyway, while I've explained why this doesn't sound right to me, I don't have the expertise to say you are NOT right. Microwave transmission is kind of the "weird uncle" of electromagnetic propagation, so I'll just sit back and watch.  :-)

I should mention that I have not been able to due flight testing with this fix because of the weather. All testing so far has been on the ground. So..be careful!

It may not be just the 2.4 transmission causing problems.  It could also be the 5.8 or even just general EMF pollution emitting from the electronics in the controller, causing problems due to the extremely close proximity of the controller to the tablet.

I don't have what I would call major problems with my FPV.  It usually works fine.  But sometimes the FPV would freeze up - this is usually when I'm approaching edge of range, which is normal - and then it won't come back when I'm back in range which is not normal.  So that's irritating as I'd have to fly it home with telemetry.  Every once in a blue moon the whole app would crash and I'd have to reboot it in the middle of the flight.  That's no fun either.  In my mind, this should never happen because my tablet has tons of memory.  This may be the answer I've been waiting for.  But it'll take 10-20 flights before I know for sure.  

Here is what we did back in the day to solve the bad GPS reception problem which seems to be similar to this.  This guy uses 3M laser printable aluminum foil.  

Mark The Droner. Cool Video. Do you know if DJI addressed the birds GPS issue in the current P3 standard?

I don't know.  They must have done something though, because nobody complains about the P3S GPS for the most part.  Looking at the two modules, it looks like they made the P3S GPS module cable shorter, and also insulated it better.  Maybe that was the fix.  

try rotating phone 180 degrees , moves phone antenna away from RC antenna .

I'M WILLING TO GIVE IT A TRY.

JoeO Posted at 2017-4-1 07:43
Mark The Droner. Cool Video. Do you know if DJI addressed the birds GPS issue in the current P3 standard?

Got my first 2 test flights in with the aluminum shield installed on my tablet holder. I am very happy with the results.
Flight 1: Only disconnected once when I took the bird out to a little more than 450ft. RTH activated, started return. It re-connected at about 250ft where I took back control and continued flying.
Flight 2: Stayed within 300ft. No disconnects. FPV video worked great, though I must say I wasn't watching the FPV all the time (hard to see on screen).
This is very different behavior from my previous two flights (without AL shield) at the same flying field. I was getting random disconnects with the bird 20ft in front of me. I believe it was interference (before the AL shield mod) from my tablet because of the close proximity to the RC's DJI stock antenna. Looks like the shield fixed the issue. I probably will try one more test run with the DJI stock antenna. Next step is to install the ARGtek antenna kit. I think the ARGtek antennas are dipoles and the DJI stocks are monopoles. The dipoles may be enough alone to fix the interference issue.

fans6d6a663b Posted at 2017-4-1 01:39
The Aluminum foil is between the tablet and the RC, not over the display.

Aloha fans6,

     This is very interesting.  I will be trying this with my nVidia Shield K1.  The sunshade I make out of a Corona Light 12-pack box could host a nice barrier of foil and be almost not noticeable.  Using USB based controllers have their own set of problems that your solution might help.  At least worth a try!

     Not too many people realize that the nVidia Shield K1 has a very strong magnetic backplate so it can be placed on metal surfaces while playing games.  Not good for flying.

Aloha and Drone On!

Mark The Droner Posted at 2017-4-1 04:48
It may not be just the 2.4 transmission causing problems.  It could also be the 5.8 or even just general EMF pollution emitting from the electronics in the controller, causing problems due to the extremely close proximity of the controller to the tablet.

I don't have what I would call major problems with my FPV.  It usually works fine.  But sometimes the FPV would freeze up - this is usually when I'm approaching edge of range, which is normal - and then it won't come back when I'm back in range which is not normal.  So that's irritating as I'd have to fly it home with telemetry.  Every once in a blue moon the whole app would crash and I'd have to reboot it in the middle of the flight.  That's no fun either.  In my mind, this should never happen because my tablet has tons of memory.  This may be the answer I've been waiting for.  But it'll take 10-20 flights before I know for sure.  

Aloha Mark,

     I will be trying this with my nVidia Shield K1.  The sunshade I make out of a Corona Light 12-pack box could host a nice barrier of foil and be almost not noticeable.  Using USB based controllers have their own set of problems that fans6's solution might help.  At least worth a try!

     Not too many people realize that the nVidia Shield K1 has a very strong magnetic backplate so it can be placed on metal surfaces while playing games.  Not good for flying.

Aloha and Drone On!