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Question about long range

bzmot

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I have just started my adventure with fpv but because I am mainly interested in travel and scenic flights rather than racing or freestyle tricks so I hope to progress to long range pretty soon. Could somebody give me a concise explanation as to the available standards for tx/rx and video? I do have DJI goggles and I suppose they will provide a decent coverage of about 1km in unobstructed terrain.

1. Are there more and less powerful dji air unit settings depending on your battery (I have been flying only tiny whoops in analog so far) and I don't have any dji air unit equipped quads yet.
2. Is crossfire a standard for analog video transmission only or for quad control also? In terms of VTX range does it beat DJI?
3. Can I combine DJI for vtx with some long range quad control options? What are those? I guess crossfire right?

In short, I have a very fuzzy image of what long range is and what options I have. Mainly I'd like to stick with DJI for vtx (because goggles..) but perhaps there are better choices out there?
I'd be very happy if some helpful soul would enlighten me...
 
HI Bzmot,
I am no pro at this either however I will try to answer your questions.
1. The DJI unit does have different power settings from 25mw to 700mw and with a very easy hack you can go up to 1200mw but that is illegal in the US. Anything over 1000mw is, however many people still do it, especially if your out in open area away from civilization
2. Crossfire is the control link standard for long range since it uses 900mhz band and you can get more range with this band. The company TBS(Team Black Sheep) that makes it also makes analog vtx's as well I believe, one is called unify. I believe if your looking for ease of setup and better penetration go with the DJI air unit. Here is a video from Zoro that he made recently on the differences between the analog and digital when it comes to penetration and the signal going around large objects like buildings. He was able with the dji system to make it all the way around the building, his friend flying next to him using crossfire with analog could not. Start watching at 7min to get to that part.

3.
Yes you can use seperate receivers outside of the dji air unit, you are not limited to the DJI controller, you can use your taranis\tango 2 or whatever when you have a crossfire receiver installed or any type of receiver you feel like you want to use. I fly my Titan XL5 with an xm receiver and it has a dji air unit. I was able to get over a 1km on my flight you can see it in the videos section.
I would stick with DJI easy to setup and best bang for your buck IMO, when it comes to range, immersion, and penetration. Since you have been flying analog already with your woops, and you have a transmitter that has a modular bay and support crossifire it might be cheaper to go with a crossfire module but that will be more difficult to setup. Good luck!
 
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Thanks a lot! Köszi! It's funny, I'm Polish and whenever I meet a Hungarian this rhyme always comes to mind "magyar lengyel két jó barát etc.", of which we have our own version too.

I watched the video. Just so I get it straight, the DJI system, if you use their radio (I wasn't planning on doing that but...), uses some proprietary protocol for the radio link too? Is it more effective than frsky or crossfire links?

If I understand correctly in this video in fact DJI beat analog because the analog pilot lost video feed. And then I guess failsafed too...

In fact is video feed usually the weak link in long range (or any fpv flying), I guess is my question? Or am I getting it wrong? So will the video feed usually disappear before you lose actual control of the drone?

I mean clearly from this video I would say that dji is the winner on video feeds. What about the control links? Do they not really matter because video will always disappear first?

Sorry if those are silly questions... I am really new at this..

HI Bzmot,
I am no pro at this either however I will try to answer your questions.
1. The DJI unit does have different power settings from 25mw to 700mw and with a very easy hack you can go up to 1200mw but that is illegal in the US. Anything over 1000mw is, however many people still do it, especially if your out in open area away from civilization
2. Crossfire is the control link standard for long range since it uses 900mhz band and you can get more range with this band. The company TBS(Team Black Sheep) that makes it also makes analog vtx's as well I believe, one is called unify. I believe if your looking for ease of setup and better penetration go with the DJI air unit. Here is a video from Zoro that he made recently on the differences between the analog and digital when it comes to penetration and the signal going around large objects like buildings. He was able with the dji system to make it all the way around the building, his friend flying next to him using crossfire with analog could not. Start watching at 7min to get to that part.
 
Your welcome! Hungarians and Polish always have been really close to each other in relations :)
If your going to use the DJI system alone with the DJI controller I would imagine that the video might go out first however I cannot be sure since I have never flown the DJI system with its proprietary control link. You do however get a indicator showing your signal strength for both video and rcsignal. I would never push to the limit, like how you see zoro did, you can see that his picture was getting pretty bad at one point, when you start seeing your feed getting pixelated and your bit rate starts to lower from its normal rate your getting into dangerous area, would be the time to turn around. DJI has fixed this on updates since the earlier firmwares it would not pixelate as much before freezing or blacking out.
I really do not know if the 5.8ghz proprietary band would be better in sheer distance(since that band wont carry as far as 900mhz crossfire) but penetration seem pretty good. If you look on youtube there have been DJI users that have gone for miles, same with crossfire. It's personal preference, but like I said it is much easier to setup a DJI system alone and be up and flying.
THe only question I have for anyone is that if your only running DJI and you failsafe and if your running GPS, will the rescue kick in if you have it set to turn on in betaflight?
That guy in the video failsafed because he lost his control link, he tries to continue because he got his control link back and re-armed it's just that he could not see anymore because his video was too fuzzy. Most people do not failsafe on video loss, it just gets worse and worse to the point you cannot see anymore, failsafe is usually when your control link is disconnected for some reason.
In analog you would want your video to go out first before your control link, but with digital if your just using DJI I would imagine that both the control link and video are pretty close to each other in when they will go out, but you will start noticing this before it actually happens.
DJI was the winner however that video was just one area, depends on the interference , I would just stick with a whole DJI setup, if you have 300 for the controller Iam pretty sure you will me more than happy with its range and ease of setup. Trust me you will not want to go back to analog. A alternative to the air unit is the caddx vista, it works with the goggles and its cheaper, If you want to fly long range and get the best bang for your buck just get the DJI controller and the flywoo explorer. It can fly up to 20-30min.

One more thing sir, you really do not want to fly farther than 1-2 miles max, its one thing with the camera drones flying out 4-5 miles but its all just for show on youtube, nobody really uses them at this distance for anything and plus they have redundant systems to return if anything happens by themselves with no pilot skill needed. On the other hand with freestyle and flying long range you really do not have this, yes you can have gps return but it's not anywhere as sophisticated and reliable, and when you crash 2 miles out your in for a search mission and maybe never finding it.
 
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Thanks again for your answer!

so wait... a 5” quad equipped with the air unit will also need to be controlled by a DJI radio ? Or am I understanding this wrong? The dji air unit is for video only (VTx) or does it include a receiver (Rx) for the control link too? I use the QX7 for now but I have my sights set on the tx16 radio master and am not too keen on using Dji’s radio. How would that work?
 
Thanks again for your answer!

so wait... a 5” quad equipped with the air unit will also need to be controlled by a DJI radio ? Or am I understanding this wrong? The dji air unit is for video only (VTx) or does it include a receiver (Rx) for the control link too? I use the QX7 for now but I have my sights set on the tx16 radio master and am not too keen on using Dji’s radio. How would that work?
The DJI transmitter only works with the air unit or the caddx vista since it has their own receivers built in. If you want to use your qx7 or tx16 you can use a separate receiver you can add to work with the air unit\caddx vista. I was just stating that using the air unit with the dji transmitter is more simpler since you do not have to add a receiver.
So if you want to fly a quad using your qx7 you will need to add a frsky receiver to your quad or have it come with one installed. If you want to fly long range and use crossfire you will need to get a module that fits in your qx7 or tx16(modular bay) and then have a crossfire receiver installed on your quad, BUT if you just get the DJI controller, you wont need to install anything else on your quad, just use the air unit or caddix vista and you can fly long range.
If you have only been flying whoops, I would continue using your qx7 for this.
If you want to go bigger for long range, I would stay simple, just get a DJI transmitter this will eliminate any other devices you will need if your going to fly quads with dji system from now on.
If you do not want to use the DJI transmitter, the Tx16s from radiomaster already comes with a R9 module inside the transmitter, so you will need a r9 receiver installed on the quad, Crossfire, like a said a separate module that connects to the bay on the back of the transmitter and also a crossfire receiver will be required.
 
Now it's all clear thanks!

I think I will indeed go crossfire then. The upgrade to crossfire on TX16 is not very pricey and I can do that.
Is there any way crossfire can get me OSD on the DJI goggles?

And one more question: so no third party radios will support DJI's control link and there is no way to get a mod for that?
 
Now it's all clear thanks!

I think I will indeed go crossfire then. The upgrade to crossfire on TX16 is not very pricey and I can do that.
Is there any way crossfire can get me OSD on the DJI goggles?

And one more question: so no third party radios will support DJI's control link and there is no way to get a mod for that?
Yes you can get your crossfire telemetry to show up on your goggles when you select the custom osd option in your goggles. You setup what you see in your osd in betaflight.
No 3rd party transmitters supports the DJI protocol as of today.

HOwever you can stick crossfire on the dji transmitter.
 
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Yes you can get your crossfire telemetry to show up on your goggles when you select the custom osd option in your goggles. You setup what you see in your osd in betaflight.
No 3rd party transmitters supports the DJI protocol as of today.

HOwever you can stick crossfire on the dji transmitter.
thank you!!!
 

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