How many satellites needed? Home lock question

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I just read a thread where someone said 9 is not enough. Surely that can't be true. Also, won't home lock be achieved on its own if you wait long enough? Can/how do you manually do it? I'm assuming on the display it will tell you if you have home lock. Planning on buying my P4 this week and I've been away from flying for over a year with my PV2+ so I'm a bit out of the loop on things. Thanks.
 
I just read a thread where someone said 9 is not enough. Surely that can't be true. Also, won't home lock be achieved on its own if you wait long enough? Can/how do you manually do it? I'm assuming on the display it will tell you if you have home lock. Planning on buying my P4 this week and I've been away from flying for over a year with my PV2+ so I'm a bit out of the loop on things. Thanks.
Yes, the display will tell you that it has satellite lock and it will show GPS-Safe to Fly.
A voice will also tell you that The Home Point Has Been Recorded - Please Check it on the Map
To get sat lock you will need to have 6 sats locked - but that's six or either either US or Russian sats - not 3 of one and 3 of the other.
But the display only shows the total number, so if you had 5 US + 4 Russian sats you still wouldn't have lock.
This isn't an issue as the GPS antenna is good and you'll get plenty more sats quite quickly if your Phantom has a view of the sky.
You'll find things have moved a long way forward from the P2V+
 
Yes, the display will tell you that it has satellite lock and it will show GPS-Safe to Fly.
A voice will also tell you that The Home Point Has Been Recorded - Please Check it on the Map
To get sat lock you will need to have 6 sats locked - but that's six or either either US or Russian sats - not 3 of one and 3 of the other.
But the display only shows the total number, so if you had 5 US + 4 Russian sats you still wouldn't have lock.
This isn't an issue as the GPS antenna is good and you'll get plenty more sats quite quickly if your Phantom has a view of the sky.
You'll find things have moved a long way forward from the P2V+
Hey Meta4, great info there man.

I take what a moderator says, like 100% but, the other day I had an actual RTH (day before my amps got here) and, well because I knew I was pushing it, I also gained a little more altitude then I thought, anyway, the craft after going thru it and watching the flight log, showed it did indeed seem to start to lower to my RTH altitude. I don't want to get into specific hieghts again (I can of course) but sure enough, by the time I regained control (a long time this time as I was threading a needle on LOS) it had lowered a few hundred feet.

I wouldn't even argue my point, as I'd actually think I was maybe mistaken somehow, before Id say you were incorrect. It just sure seemed to drop, and I thought it wouldn't no matter what? My RTH is 200m I just turned it up to that due to maybe height will help reconnect, I figure that's safer then an uncontrolled UAV.
 
I take what a moderator says, like 100% but, the other day ....

I wouldn't even argue my point, as I'd actually think I was maybe mistaken somehow, before Id say you were incorrect. It just sure seemed to drop, and I thought it wouldn't no matter what? My RTH is 200m I just turned it up to that due to maybe height will help reconnect, I figure that's safer then an uncontrolled UAV.
Moderators might make the occasional mistake but in general, the team has a pretty good idea what they are talking about.
I haven't got a P4 to check but I was assuming that the RTH programming is the same as the P3 (like most of the P4 systems are.)
But I'd be quite surprised if a P4 descends to RTH.
It would be easy to check exactly what happened and see the real numbers.
Go to https://www.phantomhelp.com/LogViewer/Upload/
Follow the instructions to upload your flight record.Look at the flight record it provides and there'll be no more guessing.

btw 200 metres is very high to set your RTH.
To climb (up to) 200 m and descend from 200m will require quite a bit of battery and take almost two minutes which would be a dealbreaker in a low battery situation.
It's probably a better idea to set RTH just high enough (plus a safety margin) to clear whatever obstacles are in your flying area.
 
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Moderators might make the occasional mistake but in general, the team has a pretty good idea what they are talking about.
I haven't got a P4 to check but I was assuming that the RTH programming is the same as the P3 (like most of the P4 systems are.)
But I'd be quite surprised if a P4 descends to RTH.
It would be easy to check exactly what happened and see the real numbers.
Go to https://www.phantomhelp.com/LogViewer/Upload/
Follow the instructions to upload your flight record.Look at the flight record it provides and there'll be no more guessing.

btw 200 metres is very high to set your RTH.
To climb (up to) 200 m and descend from 200m will require quite a bit of battery and take almost two minutes which would be a dealbreaker in a low battery situation.
It's probably a better idea to set RTH just high enough (plus a safety margin) to clear whatever obstacles are in your flying area.
If I get some time to mess with that I'll do it, is there a time limit, or flight limit on the data? Meaning, heck I've flown a bunch of times since, it may not be there?

Well, that's why I said I wouldn't want to call you out, because I'm only going by what the flight data on my tablet shows. That alone isn't enough, or good enough information to reliably say.

I agree it's high, but for where I am, with honest 90'-110' trees, they're remarkable, true tall SOBs, and with a boosted setup, I am not losing signal on anything that's not pushing the limits, I'll probably bring it back to 120m. It's just too well documented and known personally by my own 28hrs (which isn't a lot compared to some of you guys) but enough for me to know, height brings reception, usually, but I'll consider your input. I'm not being a jerk or anything, just being honest. I have to consider advice, then make my own deductions, I really don't like the idea of first losing control of my aircraft, but then to break guidelines to recover the bird on top of losing flight control, may compound my troubles.

Thanks for the GPS info Meta, and I'll likely drop it to the 400'.

I guess I am unlike the others here, I always seem to have enough juice, but that my area, if I could push it further then I would understand better, but 20m at a time for me is plenty (with 3 batteries that's well over an hour if I start charging one right away)

I did surpass a mile in my area which is further then ever before unboosted, 100' trees and being a resort area mean it's filled with both obstacles and high floor noise throughout, lousy with WiFi and other noisy frequencies.
 
If I get some time to mess with that I'll do it, is there a time limit, or flight limit on the data? Meaning, heck I've flown a bunch of times since, it may not be there?.
Your app keeps flight records until you delete them. You can upload whenever you like.
Or just replay the flight record for that flight within the app and you'll see the telemetry data there too.
 
Your app keeps flight records until you delete them. You can upload whenever you like.
Or just replay the flight record for that flight within the app and you'll see the telemetry data there too.
Well, true but if I was on a RTH isn't that info only going to be on like the built in SD card?
 
Well, true but if I was on a RTH isn't that info only going to be on like the built in SD card?
Meaning, that's why I didn't trust what I saw over what you said, I actually trust your word more then what my tablet guessed at
 
Well, true but if I was on a RTH isn't that info only going to be on like the built in SD card?
Your app stores quite detailed flight records.
Go to the flight record section and play back a flight to see how much it keeps.
Here's a screenshot from one of mine that shows it is in RTH (Mode=Go Home) and you can see the height and everything else.
You can also get it to show your joystick inputs as well.
*note* there's something wrong since I messed around with some files and now the playback is swapping horizontal and vertical speeds
i-SdfmbCj-L.png
 
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Your app stores quite detailed flight records.
Go to the flight record section and play back a flight to see how much it keeps.
Here's a screenshot from one of mine that shows it is in RTH (Mode=Go Home) and you can see the height and everything else.
You can also get it to show your joystick inputs as well.
*note* there's something wrong since I messed around with some files and now the playback is swapping horizontal and vertical speeds
i-SdfmbCj-L.png
Oh, yeah that's the log I used to come to the conclusion it dropped. I just don't know how accurate it is, for one, it shows the bird flying at an angle, yawed, because it was likely the last telemetry received.
 
I have got 3 RTH because of out of range on my P4, Once I was above my 50m RTH setting and the bird remained at it's altitude of 350 feet for the over 5000 feet trip home, it always came back and stayed at it's present altitude if it was above the set point.
 
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I have got 3 RTH because of out of range on my P4, Once I was above my 50m RTH setting and the bird remained at it's altitude of 350 feet for the over 5000 feet trip home, it always came back and stayed at it's present altitude if it was above the set point.

Yeah see, that's why I am not calling out Meta4 on what I am seeing because I have a strong feeling the app was guessing, but did realize when I regained control, it was at RTH setting (200m) and not the height I lost it at, which was like 1000'
But without telemetry, how could the app "know" what the craft was doing? What height? What yaw angle? It cannot, so I'm leaning with Meta4 and the rest of the guys that what I was seeing just isn't accurate
 

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