Stock Radio out of range

[thestone11]

During my FPV flight, about 750m away and 100m vertically I lost control with the radio. Through my screen, I can see the distance and video feed....it went to failsafe return to home. Just wondering is there anything I can add to the stock radio to have more range? or am I looking at an upgrade radio? I just like how simple the stock radio is though.

 

[Woody]

Take a look at these videos on You Tube: https://www.youtube.com/results?search_ ... ntenna+mod

 

[maxwell smart]

thestone11 Hi there. I have done the transmitter mod, with the antenna. And in my neighborhood I lose control at about 900 miters. However at the beach I can go well over that range. I will still have FPV. I believe it is due to interference in town.

 

[KraigNC]

I am having the same experience as the OP. I've been reluctant to do the transmitter mod because it's a little more involved than I would like. I've also been considering buying the new RC with the gimbal wheel. Will the new RC work any better?

 

[QYV]

the transmitter in the newer style controller isn't significantly stronger than the original, simply upgrading to the NDJ6 won't give you longer range. There's 2 main ways to extend your controller range:
1) rig a little cardboard/foil device to focus the signal from the stock antenna. not exactly but something like this. That's a Vision series antenna but plenty of guys getting better range with a device like that, search around you can find better examples of rigs for P2 RC antenna. Some of the guys posting super long distance runs on youtube like 2+ miles claim they use the stock RC / antenna with a foil rig.

2) mod your controller to accept a better antenna such as the FPVLR 2.4ghz half-sphere. This involves opening up the RC, and very carefully cleaning off the sealant gunk from the U.FL connector on the RC transmit board (it's very easy to damage the connector you must be VERY careful) and then replacing the cable with a U.FL to RP-SMA female cable and re-assembling the RC. now instead of the little white stick antenna, you have a RP-SMA female connector there and just screw in another antenna. There's videos on youtube of guys doing this and honestly they make it look harder than it is, I've done it 3 times now and I can do it in about 5 mins the trick is not to damage the U.FL connector.

prior to the mod I was maxing at 750-800m over the city, now I've been out over 1100m and not lost control. out in the country with no interference I've been several hundred meters over a mile and still had control.

If any of you live near NYC or are willing to ship the transmit board to me I would be happy to do it for you. If you want to upgrade to a NDJ6 controller anyway, you could go ahead and get that controller and once you have it paired and working, mail me the transmit board from your old controller (I'd teach you how to get the whole transmit board off it's really easy) and then I can mail it back to you cleaned and you can just swap the board into your NDJ6 once you have it.

This is a picture of the transmit board removed from the controller, with the gunked up U.FL connector, the wire is your actual antenna that runs up into that white housing you probably think of as the antenna that comes out the top of your RC. the wire just runs up inside it.

using a exacto knife, it's easy to go "down" the silver part and get the gunk released from that side, the tricky part is working along the bottom / green board part and knowing where to stop. I can post an "after" picture where the gunk is removed tomorrow night. also some better pics of the final RC

 

[thestone11]

Rather than getting a more advance radio like a higher end futaba, I like how simply the stock radio is. I think I am going to do the antenna mod. Looking forward to see the photo.

 

[PaulVx4]

I just replaced the stock dipole in my 2.4GHz controller. Here's a bunch of pics, went very well, easy.

 

[QYV]

Paul's post is perfect. the only thing I did differently was I didn't drill a new hole I just yanked off the white stick and put my female RP-SMA connector there, using the torque on the RC when I connected it back together to hold the connector in place.

Paul's is a prettier

 

[PaulVx4]

Paul's post is perfect. the only thing I did differently was I didn't drill a new hole I just yanked off the white stick and put my female RP-SMA connector there, using the torque on the RC when I connected it back together to hold the connector in place.

Paul's is a prettier

Yeah, I wasn't sure if I ever would decide to go back to stock, it was easy to just poke a hole. Or, if I end up with another antenna here, or may feed into an amplifier.

I think I have exactly what I want set up now. Still on stock dipole wires on the P2 legs (bird-side), but this spherical (circular polarized) antenna really punches. I've been told, not so much in a gain-factor, but rather efficiency. Not too directional, but certainly you have to keep it pointed towards the direction of Phantom flight.

The others I have mounted on top of my Black Pearl are also doing extremely well for my video-side.

Cheers!!!

 

[N017RW]

Paul's post is perfect. the only thing I did differently was I didn't drill a new hole I just yanked off the white stick and put my female RP-SMA connector there, using the torque on the RC when I connected it back together to hold the connector in place.

Paul's is a prettier

Yeah, I wasn't sure if I ever would decide to go back to stock, it was easy to just poke a hole. Or, if I end up with another antenna here, or may feed into an amplifier.

I think I have exactly what I want set up now. Still on stock dipole wires on the P2 legs (bird-side), but this spherical (circular polarized) antenna really punches. I've been told, not so much in a gain-factor, but rather efficiency. Not too directional, but certainly you have to keep it pointed towards the direction of Phantom flight.

The others I have mounted on top of my Black Pearl are also doing extremely well for my video-side.

Cheers!!!

Paul, what is your experience with regards to antenna theory?

To this novice, using a circularly polarized Tx antenna config. with a [vertical] linearly polarized Rx antenna config. puts the system at a disadvantage from the start. No system would be designed this way without some steep implementation limitations so I'm skeptical about any efficiency gains.

Just curious what your empirical or anecdotal results have been so far?

Thanks.

 

[PaulVx4]

I hear ya Frank. I'm scratching my head a bit on all of this too. My RF antenna experience goes back many years. I use to help folks with killer systems for their CB Radios, LOL.

But your points are well received. This setup is working, and I must say working well. Maybe a tad "directional" compared to what I had with the dipole.

I've been doing back-to-back tests with both control channel and video out my side yard. I have an area here that is TALL pine and old oak trees. I could only fly so far before either the video would drop or RTH would kick-in if I pushed past what I could talk through. Probably 10-12 flights where I would wait for my P2 to show up again. We were only talking 750 feet into the woods and I would lose connection.

I got the video working well first. I'd have great video on my Black Pearl but then no change to gimbal change requests or stick movements. It was a weird feeling. I could "see" but not control. Then the RTH would kick-in and a few moments later I had control back again. After changing to the CP spherical, I was able to keep going. I actually ran out of trees and ended looking down into a neighboring field. I was able to push to 1800+ feet before starting to lose video again.

I truly hope a knowledgable person can help reason this out. But I do have video with gauge data of an FPV over the trees. I have 120' trees in my yard that I must clear first, I lose sight of my Phantom is mere seconds after I push the right stick ahead.

https://youtu.be/ggfTQXP0r60?list=UU8xJdXqsbERwve8vhAN0dsw

 

[QYV]

I have pretty much the same setup and I experienced a noticeable increase in control range after the mod. Over the city I was losing touch with my Phantom at about 800m max, so I did the mod and now my RC antenna is that 2.4ghz half-sphere... I've been out over 1100m over the city and have never lost control.

out in the country my personal best is just under 1800m

 

[N017RW]

Ok then.

Looks like the dBi gain is enough to overcome and mis-match losses which may be occurring.

 

[maxwell smart]

https://vimeo.com/122695877

 

[QYV]

https://vimeo.com/122695877

just curious what the purpose of "copper shielding around the video transmitter" ?

I'm kind of jealous about that rubber duck antenna on the back leg for improved RC control, very good idea. did you just like, patch the cable internally or did you run a new cable all the way from the receiver board up above the battery?

 

[N017RW]

https://vimeo.com/122695877

I don't believe the added swivel-base antenna adds anything but weight.

If you look inside, electrically it looks just like what's supplied by DJI, 1/2 wave dipole (onmi), without the weight of the enclosure and need for an additional connector(s).
(Anatomy of a rubber duck: http://martybugs.net/wireless/rubberducky.cgi)

The OEM Rx antennas and their configuration on the Phantom is optimum for the P2's from-factor (i.e. vertical, omni-direct., spaced as far apart as reasonable, low, and away from body, etc)

Academically speaking, If it we're to be a 3-5dBi gain model, that further reduces it's effective area by narrowing the beam path. This may cause additional loss in some a/c orientations.
(http://www.liveport.com/wireless-antenna-properties).

If you've covered up the Video Tx amp's heat-sink cooling fins with copper tape you've reduced it's cooling and thus it's performance and life-span.

My unsolicited $0.02 but open for discussion...

 

[QYV]

If you've covered up the Video Tx amp's heat-sink cooling fins with copper tape you've reduced it's cooling and thus it's performance and life-span.

that's kind of what I was thinking too, that's why I was curious the logic/reason for it

 

[maxwell smart]

The heat fins are on the dubble stick tape. I have not had a heat problem, But I will be watching it. I saw a video on youtube about the foil wrap on the transmitter , and the guy seas it cut out a lot of static. the replies where mostly about it may over heat. But it should not be any worse then the plastic wrap that is already on the transmitter. It is a very thin copper tape. The copper tape works as a heat sink.??
I ran a new cable to phantom receiver. I don't recamend this.
It was very hard to remove the original cable. But now I can experiment with other antennas. And when I find one that is superior to stock I will brag about my range. I hope that moving the antenna to the outside of the leg will help a little. And it is kinda cool looking. I would of did the front antenna to but it was so hard to remove the cable. I think epoxy was used to keep the original cables on. Thanks for looking.

 

[maxwell smart]

Well I did some flying to day. The shielding I put on the video transmitter was causing a lot of interference.So dont do that. Other then that, It flying good.