How far can you START a P4P+?

David Cooke · Jul 25, 2017

I've been experimenting with how to conduct BVLOS ops ( Beyond Visual Line Of Sight) safely and legally . . . and became curious about how far away you could start a Mavic so I tried an experiment. My observer friend Ian took my Mavic and Phantom 4Pro+ a little over a kilometer away ( across open water for best reception)
Point C was about 1.2km and point be was about 660meters from my position at A
Neither machine used antennae augmentation. Both stock, full battery tried both 2.4Ghz and 5.6 Ghz
We communicated by walkie talkie

Mavic would barely connect at C (some intermittent video) nothing solid
P4P+ would not even connect ( note: there was a few trees but no buildings just past point B which may have interferred)
Mavic fired up and would have taken off with good video signal if the blades had been on ( Off for safety)
P4P+ Would connect but flakey video and would not accept a start signal
Both were attempted on the ground and being held overhead

Mavic clearly has a better radio and video signal than Phantom 4

At under 500m both machines will connect and engines will fire and take off is blades were used

View attachment 18057

Numone · Jul 25, 2017

David Cooke said:
I've been experimenting with how to conduct BVLOS ops ( Beyond Visual Line Of Sight) safely and legally . . . and became curious about how far away you could start a Mavic so I tried an experiment. My observer friend Ian took my Mavic and Phantom 4Pro+ a little over a kilometer away ( across open water for best reception)
Point C was about 1.2km and point be was about 660meters from my position at A
Neither machine used antennae augmentation. Both stock, full battery tried both 2.4Ghz and 5.6 Ghz
We communicated by walkie talkie

Mavic would barely connect at C (some intermittent video) nothing solid
P4P+ would not even connect ( note: there was a few trees but no buildings just past point B which may have interferred)
Mavic fired up and would have taken off with good video signal if the blades had been on ( Off for safety)
P4P+ Would connect but flakey video and would not accept a start signal
Both were attempted on the ground and being held overhead

Mavic clearly has a better radio and video signal than Phantom 4

At under 500m both machines will connect and engines will fire and take off is blades were used

View attachment 18057

Bet if you run the same test again united identical conditions, you'd get a different set of results.

David Cooke · Jul 25, 2017

We tried multiple attempts with both machines from multiple locations at different heights... same result... so same day and very similar conditions

El Schue · Jul 25, 2017

Curious as to how you are going beyond line of sight legally.

Goof · Jul 26, 2017

Lots of paperwork: https://www.faa.gov/uas/resources/e.../media/Workshop_5_Part_107_Waiver_Process.pdf

David Cooke · Jul 26, 2017

El Schue said:
Curious as to how you are going beyond line of sight legally.

Sure . . read my "BVLOS - Best Practices" HERE . . . this is Canadian Rules by the way. There are still no regulations but they are getting very close now when they published the actual proposed changes last week.

Check out other discussion on "Drone Issues" in the upper menu on in sky photovideo

alokbhargava · Jul 26, 2017

You should get better results if altitude at point A is increased by 50'

David Cooke · Jul 26, 2017

alokbhargava said:
You should get better results if altitude at point A is increased by 50'

Yes we thought of that and there was a 20 ft rise just behind me but the grounds keepers we cutting grass so we were unable to test that. The basic premise of BVLOS take off has limited use really, so it was more of a test of the difference between Mavic and P4P comm links using good/measurable lines of sight than establishing a new mode of operations. Even so, I'm still thinking about when I might find that mode useful for a mission. At least I know now that withing about 500m its possible.

Goof · Jul 26, 2017

It's very easy to have interference issues and signal degradation when flying at long distance close to the ground, let alone actually sitting on it. Panel antenna mods or even windsurfers can help a lot with getting the penetration needed to get your clean signal to the bird through or around obstacles and interference...

David Cooke · Jul 26, 2017

Good point ... will keep that in mind and test them someday

El Schue · Jul 27, 2017

Ahhh! Canad

David Cooke said:
Sure . . read my "BVLOS - Best Practices" HERE . . . this is Canadian Rules by the way. There are still no regulations but they are getting very close now when they published the actual proposed changes last week.

Check out other discussion on "Drone Issues" in the upper menu on in sky photovideo

ian rules

El Schue · Jul 27, 2017

Ahhh! Canadian rules. Makes a big difference. FAA requires an approved waiver. Like what was said " lots of paper work. I have applied for several airspace authorizations, but have only received one approval and one acknowledgement that the request was even received. 3 others have gotten zero response. I emailed the help desk and never heard back from them either..

David Cooke · Jul 27, 2017

El Schue said:
Ahhh! Canad

ian rules

Who's Ian?

El Schue · Jul 27, 2017

Last half of Canadian.. first half is above your post. Not sure how I did that.

racman66 · Jul 31, 2017

David Cooke said:
I've been experimenting with how to conduct BVLOS ops ( Beyond Visual Line Of Sight) safely and legally . . . and became curious about how far away you could start a Mavic so I tried an experiment. My observer friend Ian took my Mavic and Phantom 4Pro+ a little over a kilometer away ( across open water for best reception)
Point C was about 1.2km and point be was about 660meters from my position at A
Neither machine used antennae augmentation. Both stock, full battery tried both 2.4Ghz and 5.6 Ghz
We communicated by walkie talkie

Mavic would barely connect at C (some intermittent video) nothing solid
P4P+ would not even connect ( note: there was a few trees but no buildings just past point B which may have interferred)
Mavic fired up and would have taken off with good video signal if the blades had been on ( Off for safety)
P4P+ Would connect but flakey video and would not accept a start signal
Both were attempted on the ground and being held overhead

Mavic clearly has a better radio and video signal than Phantom 4

At under 500m both machines will connect and engines will fire and take off is blades were used

View attachment 18057

Hi Dave, I've been trying to use the same technique to confirm range capability for 3 antennae's I'm testing - 4Hawks Raptor XR vs DBS02.2 vs 5 Dbi wands.

Basically it doesn't work when standing at ground level, even when across open water!! The best I could do was 1.6km with the AC and RC held above your head and only the Raptor XR would connect. I would loose video once I placed the AC on the ground but I was able to get command control and take off. I also found that my android tablet would connect sometimes and say it found a Phantom 4 Advanced, I only have a Phantom 4! The Raptor XR should be good for over 20km. I agree that one end needs to be elevated for this too work.
thanks

David Cooke · Jul 31, 2017

racman66 said:
Hi Dave, I've been trying to use the same technique to confirm range capability for 3 antennae's I'm testing - 4Hawks Raptor XR vs DBS02.2 vs 5 Dbi wands.

Basically it doesn't work when standing at ground level, even when across open water!! The best I could do was 1.6km with the AC and RC held above your head and only the Raptor XR would connect. I would loose video once I placed the AC on the ground but I was able to get command control and take off. I also found that my android tablet would connect sometimes and say it found a Phantom 4 Advanced, I only have a Phantom 4! The Raptor XR should be good for over 20km. I agree that one end needs to be elevated for this too work.
thanks

THanks for that new data . . . I had another odd even yesterday . . a "commanded landing" at the edge of a No-fly zone as I flew towards it legally with the machine supposedly UNLOCKED. It landed on it's own and I was unable to prevent it. . . fortunately I was over a narrow path with water on one side and cornfields on the other. It was about650ft away. I COULD NOT CONNECT OR RESTART and got only intermittent video. I went through the UNLOCK process again ( very useless process) and took several attempts to finally restart and flew it back at 10ft AGL . . . very annoying but could have been a disaster without that 6ft side pathway.

David Cooke · Jul 31, 2017

Racman . . do you know about signal interference with spread spectrum. How susceptible are Phantom transceivers to radio interference outside the 2.4 or 5.6Ghz band? . . . anyone got info or actual testing on that?

racman66 · Jul 31, 2017

David Cooke said:
THanks for that new data . . . I had another odd even yesterday . . a "commanded landing" at the edge of a No-fly zone as I flew towards it legally with the machine supposedly UNLOCKED. It landed on it's own and I was unable to prevent it. . . fortunately I was over a narrow path with water on one side and cornfields on the other. It was about650ft away. I COULD NOT CONNECT OR RESTART and got only intermittent video. I went through the UNLOCK process again ( very useless process) and took several attempts to finally restart and flew it back at 10ft AGL . . . very annoying but could have been a disaster without that 6ft side pathway.

**** that's scary!! P4P+? Have you got the latest firmware on the AC/RC? I'd start a new thread on that event...

racman66 · Jul 31, 2017

David Cooke said:
Racman . . do you know about signal interference with spread spectrum. How susceptible are Phantom transceivers to radio interference outside the 2.4 or 5.6Ghz band? . . . anyone got info or actual testing on that?

Hi Dave, yes I think they are very susceptible to surrounding Wi-Fi interference, hence my testing with aftermarket antennae mods. I couldn't go more that 250 m at my local suburban neighborhood park before video signal loss. You should be better with the P4P+ as it will default to 5.8Ghz. I run a manual channel 20 for 2.4Ghz and reduce the video transmission rate to 4Mbps on the P4.

David Cooke · Aug 1, 2017

Thanks for that . . very helpful . . explains why I'm getting more weak signal issues and now that I think of it . . it has only been recently and after changing to 8mbps video. Will go back to 4 and see how much that is effecting things. I've always updated to latest versions so if that works with 1.04.0206 I may give it a try. . . no response from dji so far