GPS reception strength

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Hi :)

I've been struggling on and off with GPS reception on my P2V+ (I'm fairly sure it's not a v3).

Since the very first flight, GPS has been sketchy, and my satellite count has dropped off whenever I've been recording video. So I tried the cable tuck / foil mod, and that didn't really seem to make a great deal of difference - so this morning I followed the advice in another thread about firming up the connectors in the plug - and I was pleased to see a very quick pick up of 5 satellites in my back garden.

I assumed I was only getting 5 due to being in the shadow of my house, so I double checked reception / visibility in the GPS status app, and I was shocked to find that 16 satellites were showing with me stood in the exact same location. My phone got a lock within 5 seconds.

I know it's not a fair comparison as there's far less electrical noise on my galaxy S5, but still...

Is the supplied GPS receiver just not that sensitive? Should I have allowed a lot more time for the phantom to acquire more satellites? Or should I consider upgrading the receiver?
 
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Check this out and try this use an anti static bag like the ones computer hardware comes in .
 
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Meta4

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Using the Phantom where a chunk of the sky is blocked might be your problem.
The GPS Status app will be reading US & Glonass sats (if the phone is able to) while your Phantom will only read US satellites.
Next time you use it check to see if the GPS Status app has squares and circles like this:

Circles are the US sats, squares are the Russian Glonass sats.
In this screenshot, there are 10 sats that would be available to the Phantom.
The GPS status app also shows you where in the sky your sats are and that will give you an idea of whether you have a large area of the sky blocked.
 
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Using the Phantom where a chunk of the sky is blocked might be your problem.
The GPS Status app will be reading US & Glonass sats (if the phone is able to) while your Phantom will only read US satellites.
Next time you use it check to see if the GPS Status app has squares and circles like this:

Circles are the US sats, squares are the Russian Glonass sats.
In this screenshot, there are 10 sats that would be available to the Phantom.
The GPS status app also shows you where in the sky your sats are and that will give you an idea of whether you have a large area of the sky blocked.
That explains the discrepancy, thanks mate :)

I'll test it out properly in my flight test area (the field behind my house!) this afternoon.

Looking at my screenshot, I can see 7 that are 'eligible'.

 

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+1 on msinger suggestion on antenna upgrade.

takes under an hour and your issue will be resolved nicely. I pretty much get sat lock anywhere anytime now that I did my 2 P2's,
you may as well do the foil upgrade as well.

good luck and have fun flying
 
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I've ordered the upgraded puck. I have a nice gas powered soldering iron & the associated tools from my RC car racing days... but I'm not looking forward to the mess my dremel causes when it comes into contact with polycarbonate!
 
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I've ordered the upgraded puck. I have a nice gas powered soldering iron & the associated tools from my RC car racing days... but I'm not looking forward to the mess my dremel causes when it comes into contact with polycarbonate!

I was able to change the antenna without cutting the ribs out of the shell. Just be careful when tightening the screws back in.... try test fitting first before making the "mess'
 
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So the mod is done :)

removing the original solder from the PCB on the GPS module was a pain in the posterior, but I got there in the end.

I started everything up and left the Phantom outside by the shed. It's not a brilliant area for a clear view, so I was pleased to see that 7 satellites eventually showed up on the count - unfortunately starting to record reduced this count to 4/5, so obviously the camera is interfering - but still, with heavy clouds in a cluttered area that's not too bad. I'll have to try again tomorrow when hopefully the skies will be clearer. The K factor was at 5 when I did the test - would this be a factor?
 
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So the mod is done :)

removing the original solder from the PCB on the GPS module was a pain in the posterior, but I got there in the end.

I started everything up and left the Phantom outside by the shed. It's not a brilliant area for a clear view, so I was pleased to see that 7 satellites eventually showed up on the count - unfortunately starting to record reduced this count to 4/5, so obviously the camera is interfering - but still, with heavy clouds in a cluttered area that's not too bad. I'll have to try again tomorrow when hopefully the skies will be clearer. The K factor was at 5 when I did the test - would this be a factor?
.
I wrapped the gps wire completely with foil to plug and then used shipping tape over that so no shorts.
since I had the alum tape also fit some under between bottom plastic and gimbal where I could

I would say wrapping cable did most to help after antenna. and yea that plug wiggles , so I used the cable tie to jam it tight

it would be normal 1st time to take a while as all the data is loaded into gps
 
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It is shocking how such a critical piece of stabilization data is fed through such a loose connector!

I'll take the shell back off again tonight & wedge it in tight.
 
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It is shocking how such a critical piece of stabilization data is fed through such a loose connector!

I'll take the shell back off again tonight & wedge it in tight.

wrap that gps lead and the even the black socket , I figured the more I can cover the better since covering most of it is proven to work better.

I even used some alum tape around the wifi module seams .....I got tired of all the screws in caseso I went nuts on anything I could last time I had it open. lol

with that in mind, maybe do the wifi heatsink update while it is open. A little PM cant hurt

good luck and have fun flying
 
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Thanks for all the tips guys. After an extended session this afternoon it would seem that the GPS issue is fixed for now. I was easily getting 7, sometimes even 9!
 

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