Dragonlink Relay, Using Radiomaster TX16S and FrSky XSR Receiver

[@dougmcpheters1546]

Golly! I just became all the more impressed with Dragon Link. Especially with the Dragon Link software behind it.... Thanks Keith! Good one man!

[@EnglishTurbines]

A neat solution to a few technical problems...Good to see DL revising their GUI...unlike IRC and EZUHF...

[@bonafidepirate]

Yeah the Dragonlink software is pretty nice, the system has loads of features and capabilities, and the software makes it relatively easy to manage. lol

[@MCsCreations]

Great video, Keith! Thanks a lot! 😊 Stay safe there with your family! 🖖😊

[@ecor1987]

Hi Keith, I came across your video here, because I intend to setup a relay with DL as well. I have a couple of questions: Why not just set all channels to "None" that you wish to ignore, instead of going for the -100 throttle in a fail safe scenario and only adjust Channel 6 (your RTH)? And why did you have these other channel values set, I think I saw some small values for CH2 and 3. Thanks

[@npcfpv9542]

I'm looking to do this with crossfire for winter flying or even flying inside my rv to attract less attention. I think I physically understand how to set this up. But have one question: How is your radio's internal frsky tx able to send one last command to change the state of the channel for RTH before it loses link? Thanks for your videos!

[@charlesmcguire9711]

Hey, this is just the video I was hoping someone would make! ;-)It's like magic. Lol thank you Sir.

[@mkolesnik]

Hi , just curious how is your latency on this relay? i tried 2 different frsky RXes (X8R and jumper R1-D16) and not to happy with relay latency and "glitching" of plane controls (servos).

[@sutoposidiklawajo9540]

Hi Keith, I have a radiomaster problem with ezuhf. There is still channel twitching even though shielding has been done. 😢 

[@umeshjadhav3326]

I could not find any info on it ........Relay or repeater, Is it possible with crsf module ??

[@bonafidepirate]

It should be possible if you use a PPM input on the Crossfire, but you'd lose a lot of the features not having CRSF protocol between the radio and Crossfire module which is kind of it's strong point.

[@jetrg12]

Bonafide, I have setup mine all works well thanks, however I can only get 8channels out of my frsky xm+ to my ezuhf, either ch1 to 8 or 9 to 16, when bound directly in ppm without through the relay I can get up to 12 channels of control, any idea? When binding my taranis to the Xm+ it forces me to chose eithet ch1-8 or ch9-16 but doesn’t allow me to output all 16channels in the sbus stream

[@bonafidepirate]

Have you tried both PPM and sBus? (I'm not farmiliar with the xm+, not sure what options it has) The 1-8 / 9-16 option won't affect the serial stream though, it only tells the receiver which set of channels to output on the PWM pins, useful if you need more PWM channels in a large model, you can map the second set to a second receiver, Oscar explains it good here - oscarliang.com/rx-bind-option-ch1-8-ch9-16-telem-on-off/ The xm+ instruction sheet suggests it puts out 16 channels on sBus (www.frsky-rc.com/wp-content/uploads/2017/07/Manual/Manual-XM%2B.pdf) I would expect it to be working. I know the Dragonlink will only use 12.

[@jetrg12]

Thanks for your quick reply, I think I found my solution, as I am using a sbus to cppm converter (frsky one) it looks like I have to jump the two pins on it in order to get the 12 channels I will try it this weekend, see here www.rcgroups.com/forums/showthread.php?2484701-Dragon-link-repeater-using-FrSky-XJT-and-X8R

[@jetrg12]

That was it! I put the jumper on the frsky sbus to ppm converter and I got my 12 channels!

[@bonafidepirate]

@@jetrg12 Good deal, glad you got it figured out! lol What's the reason for using a converter though, and not running sbus directly from the XM+ to the Dragonlink transmitter?

[@jetrg12]

@@bonafidepirate I am using ezuhf, it supports only ppm

[@100SteveB]

Very interesting video. I have need of something similar to this because I live in a dip in the terrain. I am right beside a steep hill, and a 200m trudge up the hill gives me views for miles around. I would love to be able to fly from my shed, like you do, so having a relay like this would be great. I have already set up a video relay - just a simple case of having a video rx and tx mounted on a tripod on the top of the hill. But could not work out how to do the same with my radio. I am using the Frsky R9 at the moment, but i am now thinking of moving to DragonLink, unless i can figure out if it can be done with the R9. I think I do spot one weakness in your set up though - unless I misunderstood, what happens if the Frsky receiver quits for some reason? It won't be able to transmit your custom values to trigger the failsafe on the DragonLink. It's a shame that the DragonLink does not initiate a failsafe upon loss of signal from the Frsky. If that is the case, maybe DragonLink could fix that issue with a software update. But certainly an interesting video, certainly got me thinking! Thank you.

[@bonafidepirate]

Hmm, now you have me thinking. There's an option on the alarms page in the the Dragonlink software for "PPM Lost", which suggests it will in fact detect a loss of PPM signal on it's input... lol Maybe that's the way to go instead of sBus. I've play around with it later, might end up changing... lol For R9 you should be able to set this up the same, but using PPM out of the 2.4GHz receiver, and using the R9M in PPM mode. You wouldn't be able to set up the R9 in OpenTX, but would have to use the DIP switches on the back of the module to configure it. That should work, in theory.

[@100SteveB]

@@bonafidepirate It's a shame the DragonLink will not simply detect a loss of the sbus signal, that would save switching to ppm, lol, been a while since i used ppm. But I will certainly look into something similar with the R9, just had a quick look at the manual and it does look promising. I shall have to experiment :-)

[@bonafidepirate]

@@100SteveB FYI, I just switched to PPM and checked, everything still works the same, the only added benefit is that the DL will sound it's alarm if the receiver stops sending a valid signal. It doesn't do anything with the channel inputs/outputs, just keeps transmitting the last good input it had. I'll stick with sBus. ;) It's also worth mentioning, Mike @ Dragonlink has stated before that this is the intended behavior, not detecting a failsafe on the input. (See here - www.rcgroups.com/forums/showpost.php?p=39282966&postcount=68201) Personally I'd like to see it at least as an option you could switch on. Maybe there's some technical limitations or something preventing it. I couldn't say!

[@100SteveB]

@@bonafidepirate Very strange that Mike should think the lack of failsafe on the loss of the relay signal is not a problem, especially seeing that it worked in the V2 version according to that post. Does not make sense - especially if the relay and main Dragonlink unit are in a remote location. I have thought of one way that might get around it, I think some of the Frsky rx's can be connected together, so that if one fails the other will carry on like normal. I have got that exact set up on one of my builds - R9mini and a R9mm linked together. I am fairly sure you can do the same with some of the 2.4ghz rx's.

[@stevefox3763]

could the same setup be used with an R9M or QCZEK module? having a link like that would be perfect for flying from inside my car in the winter!

[@bonafidepirate]

You should be able to do a relay with the R9M, but instead of sBus out of the 2.4GHz receiver you'd use PPM, and use the R9M in PPM mode. You would use the DIP switches on the back of the module to configure it, instead of doing it in the radio.

[@stevefox3763]

@@bonafidepirate yay! Thankyou, I'll get playing with it and see what results I get :)

[@twinturbostang]

Is it possible to get telemetry back through the relay to the radio?

[@bonafidepirate]

I haven't experimented with that at all, but it sounds like this could be useful... lol github.com/zs6buj/MavlinkToPassthru/wiki#relay-mode

[@tankogenonrcgroups9750]

You could invest in a ext antenna on the roof that be cool!

[@rodeopilot7495]

👍👍👍great info

[@blise518B]

Great setup. Is it possible to get telemetry on you radio this way?

[@bonafidepirate]

Maybe, I'm honestly not sure as I haven't tried it. I may experiment with that later and see what kind of telemetry you can pass over the 2.4GHz link. As of right now the plan is to get Arduplan telemetry back to the Dragonlink module as normal, then connect that to a PC/phone/tablet etc. via bluetooth.

[@blise518B]

@@bonafidepirate I usually use I Nav so it’s mavlink telemetry same as in ardupilot I think. You would need an extra cable from the dragonlink to the 2.4GHz reciver to send the telemetry i guess. Or something like Fport were it does everything over one wire.

[@VincentFischer]

Why the battery instead of a DC power supply? Are DC power supplies too noisy?

[@bonafidepirate]

Just so it's sort of self-contained. In all the years of flying here, I've only lost power once while flying, but I did have my ground station running on A/C power at the time... lol Luckily I was flying close in and just about ready to land when it happened, so I just landed LOS. Had I been out a ways it would have been a bigger issue. RTH would save you, but I had no flight controller in that plane anyway. It's never happened again, but I haven't had to worry about it either.

[@mrreddog]

@@bonafidepirate This is exactly the kind of stuff Ive only been dreaming up in theory. Its awesome to see you actually putting it to work, love it. Are you doing 5.8 relay for vtx too? with tripod mounted antennas outside the shack? or cables running into shack into Eagle Eyes??

[@bonafidepirate]

@@mrreddog I'm using cables, partly to avoid issues with 5.8GHz WiFi, but also to get power out to the receivers from the same battery that runs everything else, so one less to remember to charge... lol