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SmartLink - Digital video, telemetry and control for 20 km

Yes, self centering throttle.

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Valid point. Which actually makes my original question on the cost even more valid. This new device does not have any integrated controller or display. You need a USB joystick, presumably using RC override through telemetry. And you need a tablet or PC for video and GCS functionality (or two if not using a combined app solution. Which further begs the question… what about this costs $4,000??.

I’m not saying this is a bad device. It appears to be a great thing actually. I’m just having a hard time wrapping my head around where $4,000 worth of features are hidden in this.

Well, don’t buy it, then. If they can offer a a product that is not limited with regards to it’s implementation into an existing eco system like the herelink, then it might have value for some.
Further, it’s not neceesarily using RC override through telemetry. You can quite easily send control signal alongside video and telemetry…and you’re standard Taranis works quite well as a USB joystick, should it have to.

Thanks but I’d rather listen to the manufacturer’s response to my question. You have perfectly good points about it usefulness, but “then don’t buy it” is not a productive or useful answer to a perfectly legitimate question.

It is not. Herelink is a nice drone controller good for about a 2-3 Kilometers in real-world urban 2.4Ghz environments according to some tests I have seen.

Digital video gets very expensive if it is truly long range, robust, and low latency. Not that I am defending its price, mind you. But you will spend about 2-3K for a 15KM system from Foxtech that does the same but with 200ms latency. If this truly does 20ms then it is using some very expensive components…

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Nice video. But you really should find a way to do a longer range test if you really want to impress. Strap it on a plane and see how far it will go…

Maybe part of the reason I’m questioning the price is because I’m not giving much credence to the range and latency advertisement.

  • Lots of companies like to throw amazing numbers in advertisements, but often there is nothing backing it up. Right now, there’s nothing backing it up.
  • The latency for control is advertised as “less than 20ms”. But then in the specs, it says latency is “<100ms”. Now we’re contradicting specs in one advertisement. Which is it, 20 or 100?
  • The specs say power up to 1 watt, but that 's not necessarily legal. They conveniently do not list what the range and latency is at any specific power outputs.
  • They do not correlate distance and latency. Is it 20ms at 20km at 1 watt? Or is 20ms only under some conditions with some settings in some places that made for a good advertisement spec?
  • They don’t actually say what method of transmission they’re using. Just saying they use MIMO doesn’t answer the question. I presume it’s some kind of WiFi, but I don’t like assuming.
  • The video posted in this threads shows decent quality video. But it’s only at 1.3km over flat terrain, which is really nothing super special.

So this advertisement has a lot of open ended “non-specific specifications” and contradictions. At $4,000, I shouldn’t have to ask these questions. This could be an amazing piece of equipment that defies everything else, providing 20ms video at 20km range. And it seems like that’s what they’re hoping people assume. But it is actually completely unknown what this can do, when, and how.

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Well yes. At that price it would need to perform at those specs at stated range, or something close. No argument there.

Skydrones do make decent kit so maybe Kirill will elaborate. It is not an unreasonable question to explain the value proposition.

Something that has been glossed over that I noticed in the video.
Yes they give good numbers but check out the latency that is evident in the video.

Something doesn’t match.

could you please elaborate as to what you were looking at for the rest of us peons that may not see the latency you do?

I truely appericate you bringing this new option to us, don’t worry folks will always hate tis the nature of the beast! Keep up the good work!

@Pedals2Paddles yes the herelink may be whatever price (800usd), as @Implicit pointed out it really isn’t suited for fixed wing, it is also pretty much in constant development, supposedly will support only solex (once final release), cool if you have a 3dr solo as not a lot of people use solex. The herelink currently does not support MP or RTK gps, its missing so many supposed features that I have not seen in the past 4 months since its second beta release, and there are a few posts of major distance issues! The herelink is not even in the same category as this, would be like comparing the DJI lightbridge to the herelink! hahaha not even close, apples to oranges!

Thanks a lot for the comments, feedback is appreciated. I’ll cover most interesting questions:

Unfortunately not, this leaves $1000 for datalink which is below system manufacturing costs.

Yes, you can easily use joystick connected to USB port of only one gadget (laptop, tablet) for manual control. Video is in the same app (SmartAP GCS, QGC, Mission Planner). Worth noticing - SmartLink supports 2x HDMI inputs and simultaneous streaming.
Having controller / display integrated or not - it really depends on the application. And there are a lot of them where datalink is needed as datalink only.

This is scheduled, more video coming soon.

True, more video to prove will follow soon. The product is quite new and it’s just not that easy to fly legally 20 km, but we and our customers / partners work on that.

Difference between control latency and video latency should be considered here. Control latency is 20 ms which allows comfortable manual control (you don’t see the difference compared to conventional RC). Video latency is 100 ms average, it depends on resolution, bitrate, fps, range. It varies from 50 ms to 200 ms.

FCC = 30 dbm / 1W, CE = 20 dbm / 100mW
Range / latency depend not only on output power but also antennas, noise level in the area and again the video quality (optimise for quality vs latency).
In average you should expect 20 km FCC, 6-8 km CE.
Output power is configured in the settings, so users can stay within their local regulations.

It’s 20 ms for control at 1 W at 20 km. For video it will be towards 150 ms if you want have decent quality / fps.

We use BPSK, QPSK, QAM modulation with dynamic switching to adapt for RSSI / SNR / throughput.

I’m totally agree with @Matt_C, Herelink is nice but it’s different and a bit limited - only Android, only specific QGC version, fixed screen / gimbals. There is a lot more hardware / software people want to run and we provide this option. It’s more about B2B / OEM rather than hobby though.

Is this running a microhard chip in it?

Have a look at the latency evident here

Asking questions about product information that is missing or contradictory in the advertisement is not “hating”. I don’t blindly cheer for products (any of them) without data and answers to justify the cheering first. That’s not helpful or productive.

Thanks for following up. So I have some follow ups :slight_smile:

So am I correct in that control is using RC Overrides through telemetry then? Not anything special or unique to this product. No different than RC Overrides through any other telemetry link? The advertisement goes to great lengths describing control as something separate and unique with this special low latency. But RC Overrides is on telemetry and not unique. Not suggesting it’s bad. Trying to clarify if it’s something unique or not?

Thank you for clarifying this. It was quite obvious many people were reading your advertisement as 20ms video latency which is not the case and is probably not even realistic to achieve. 100-200ms video latency is pretty normal. The Solo’s video stream is on the higher end of that range.

So is it WiFi or LTE-U?

Then how do you know it will reach 20km?? Is this range just based on the general math of WiFi and LTE-U at 1 watt with ideal antennas? Or have you actually taken it out in the real world and flown it 20km away? If so, can you explain under what conditions and equipment you obtained this 20km range? In a desert with high gain directional antennas? With the included antennas? In a typical suburban environment?

Looks similar to this on specs:

We have been using them for while now and in real world with good antennas at 1 watt is far from reaching 20km. I would say 5-7 km on ideal conditions at 1 watt is more realistic. At 100mW 1-2km.

If it is a completly different product than my apologizes.

I was thinking microhard myself. I am a little suspect of that 20km range without high gain directional antennas. What do you pay for those modems if I may ask?

The HereLink uses LTE-U (aka "LTE over WiFi) at the same power restrictions and the same theoretical range specs listed here. So just guessing you’re using the same or very similar technology.

Range testing with the HereLink’s stock normal antennas has been documented on paper and video for reference. The longest I’m aware of was tested over water, so arguably perfect conditions. They got out to 16km and still had very strong signal. They ran out of coastline at that point and couldn’t physically travel further to see when it would drop out.

In a more typical land environment, the range was significantly less, generally single digit kilometers, which I think is what most people would expect of the technology. Everything else on 2.4ghz is going to reduce the range.

Since I doubt the SmartLink has a magic bullet to overcome everything else on 2.4ghz, is reasonable to assume the actual performance of the SmartLink will be similar to a HereLink or other similar devices using similar technology and antennas? If extensive real world testing in the wild with the SmartLink hasn’t been done yet, this would at least give some baseline expectations.

Agreed, I was also frustrated I ran out of coastline ;).

As with all these systems antenna, local interference and other things come into play, I wanted to test the headline figure and I’m 100% confident it can achieve it but like all things outside factors play their part.

I’d love to have a closer look at this system but at that cost it’s not likely to happen for me, I wonder if this is also based on the same backend as Herelink using fish ?

Herelink has come under a lot of criticism of late, some of it fair and some not so, yes the development has taken longer than anyone would have liked but I still strongly believe it’s going to be a very important product. With the updates to the core system that will bring multi RC and more options around multi node use but that’s likely not going to make the next release though.

Solex will resolve a lot of the issues as it’s got far more functionally around the buttons I believe and hopefully Profi will be able to get that out soon, today it’s not perfect but it’s a very decent start but it won’t satisfy all users.

As for the throttle there is a fairly simple mod to the hall affect gimbal that can be done to remove the spring and adding a washer to the gimbal to give what fixed wing users want of a manual throttle that holds, no ratchet but it will hold stiff. I have been meaning to do a video on it but just not had a chance but will get it don’t this week as I have seen a few posts on it.

But it could affect warranty so want to be clear on that.

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I’ve tested microhard 2.4ghz out to just over 11km, with 12db margin, so 20km with 2.4ghz cofdm is feasible.
Almost all of these type of datalink separate control and payload, so I don’t see that as a weakness: just a necessary compromise.
Microhard and Taisync are probably better comparisons than herelink: being tied to a handheld controller limits herelink somewhat.

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