When you get it let the group know what you think.
I am going to go after one myself.
Will do Ricky and as long as the HDMI with low latency works and QGC Iām a happy especially after my last purchaseā¦
Hi Again Ricky
This is so true very supportive so far since ordering Mk15 I have extended the process time as itās a brand new product to help them
Get it right requested by them to make sure itās all good on arrival
Cant fault them
Steve
Hey Steve.
I know they are in the middle of their last pre production testing today, this is something they do in preparation for release.
Thanks for your post, Ricky. The team just got a very successful test.
Distance: 10,044.3 m @ Height: 120 m
1080 p @ 30 fps and 3.5 M bit rate
Still in full control!
*This is a prototype, not the final product.
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Hey Frank
Awesome news. Are you saying the team got 10km at 120 meters, thats incredible range.
I donāt know why people bother with long range fpv system builds when this gives you 10k right out of the box with video.
Awesome.
I think 10km is the limit at 120m altitude, but not because of the radio. Itās because of the curvature of the earth. In perfect conditions, over the ocean, if the transmitter is at 1m, and the vehicle (copter or plane) is at 120m, the signal canāt go more than 10km. But if you can get the transmitter up to 8m, you could probably go 20km.
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Thatās a really interesting analysis @dale2020
I confess I had not considered the curvature of the earth since my days in the ham shack 40 years ago.
Ya got to admit 10k with no special hardware, no antenna tracker and such is pretty good results.
This is because you donāt just have to think about a straight line-of-sight between you and the vehicle - you have to include the Fresnel Zone - an area above and below the line-of-sight. the lower the frequency, the bigger this area is. At 2.4ghz, which I think the Siyi radioās use, and at 10km distance, at itās widest point itās 17.6m.
to go more than 10km, you would want to be on the roof of a building or on a hilltop. Or, of course, fly the vehicle very high, like 1km or more.
@dale2020
Ok so not sure I completely understand what your getting at but will give it a try.
The fresnel zone in the example you posted above is 17.6 metersā¦so basically you need to be 8.3 meters or more above the highest object between you and the receiver for clear transmission of signal. Anything less means that there are objects that would introduce interference into the transmissionā¦did I get this rightā¦do I get a gold star hahahaha.
Also the video signal would have a Zone height of 11.4 meters at 5.8ghz. So the higher the frequency the narrower the zone and the less likely obstacles would come into play.
Also the video on the SIYI unit is 5.8ghz if thats of any use to you.
almostā¦ the 17.6 meter fresnel zone at 10km distance is the maximum - right in the middle at the 5km point. itās an ellipse that narrows at both ends.
the SIYI uses 5.8ghz for video? are you sure? I doubt that very much. if so, youāre right, the fresnel zone is half the size at double the frequency, but 5.8ghz is absorbed by oxygen more than 2.4ghz, so itās range is lower. No way youād get 10+km with the low output power of 100mw or 200mw they claim.
I donāt think SIYI even has a āvideo signalā. I think itās a single, bidirectional digital data link of 3-5mbps carrying RC, mavlink and h264 or h265 video. This is a huge leap forward from traditional hobby RC, which relies on 3 different frequencies and technologies to accomplish RC, telemetry and video.
I am pretty sure about the 5.8 but @SIYI Frank would know better then I. You might be right it could be what you suggest. I am not an expert in this field by any stretch of the imagination. Either way this is all pretty interestingā¦Learning something new.
At the end of the day itās pretty cool to get 10km with video on a handheld device. No antenna tracker. No special antenna placement. Just turn it on and enjoy.
That said If I understand the fresnel stuff and everything else you say. You would need to have nearly clear line of sight to the receiver to get that performance. So flying out to sea or over a lake would be perhaps idealā¦maybe a salt flat. But in a treed environment like most of North America. That distance isnāt likely possible. To much in the way.
But that is true of any system I think.
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Ricky is Right.
MK15 does use 5.8 GHz and 5.8 GHz only for all three links. Under FCC rules, max RF power is 30 dBm (1 W, direct output from transmitter without antenna gain). MK15 system outputs 27 dBm. We believe it is legal under CE rules as well.
yes, I agree - and none of what Iāve said really matters. what Iām really trying to say is that the range of this radio sounds like itās outstanding, but any radio, regardless of what itās range should be, will have short range if the earth gets in the way. So when people start receiving this radio and testing itās range, be suspicious of reviews which complain about short range if they fail to prove that they have kept a clear line of sight PLUS the fresnel zone.
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5.8ghz has a very small fresnel zone, and less interference than 2.4ghz. And 27 dBm is a lot of power. Iām impressed - I think this radio has been well designed should perform very well.
Are you shure? As far as I know, under CE rules generally only 14dbm (25mw) in 5.8Ghz are allowed. Higher output power is restricted to special applications and/or regulations.
can you connect the video to a bigger screen?
Itās my understanding that you can output hdmi to monitor or even goggles.
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nice, thanks you riky