Upgraded GPS Antenna-10 Satellites

cneedelman · Aug 9, 2017

I was having trouble getting 6 satellites after replacing the shell on my P2. I'm aware of the interference issues with the older Phantoms. I was going to try the copper tape, but decided to buy the kit with the higher gain antenna and shield. Now I get 7 sats within a minute or 2 and 10 after a few. Well worth the investment in time and money.

J Dot · Aug 10, 2017

Also
View eBay for a guy from the U.K., selling ( GPS BOOSTER ) I now use them on all of my birds, coupled to the 4mm antenna upgrade! Get way more satellites and stronger signal, will lock 11 satellites INDOORS ( in my bedroom! ) just an insert you put in, no wiring, nothing, just clip in and go, also won't void warrantee! Just a heads up!

J Dot

LightBrigade · Oct 13, 2017

J Dot said:
Also
View eBay for a guy from the U.K., selling ( GPS BOOSTER ) I now use them on all of my birds, coupled to the 4mm antenna upgrade! Get way more satellites and stronger signal, will lock 11 satellites INDOORS ( in my bedroom! ) just an insert you put in, no wiring, nothing, just clip in and go, also won't void warrantee! Just a heads up!

J Dot

Hi- Do you have a link for the model you use? There are lots of options on eBay UK, thx!

J Dot · Oct 13, 2017

https://www.ebay.com/itm/253075538892

And

J Dot

LightBrigade · Oct 13, 2017

Thank you!! I’m getting one right now!

J Dot · Oct 13, 2017

If you get more than one he gives a price break, but I buy 5 at a time, I always install them on the units I repair for friends, and members! Funny, as I've always wanted to rip one apart, just to see what's inside! Lol. Not sure, just know they work!

My first one, after install, turned on bird to do PC stuff, and green lights flashed, I thought, WTH?
Turned on app, 11 satellites, in my bedroom! I was Sold!

Not that you need multiples, more of a for your info. Kinda thing, the U.K. guy is really cool. And a cut up on the phone, as I once wanted to buy bulk, and talked to him about it! He said he'd rather sell them one at a time ( more of a hobby of his ) did not expect the steady flow of consumers! Lol

J Dot

LightBrigade · Oct 13, 2017

Have ordered the Phantom signal booster, do I also need the GPS Glonass Patch unit as well to make it work?

Also, one more question if you don't mind:

I have a P2 non-vision, HD 3D, go pro, iosd mini, video Tx, and black pearl 7 inch setup.

My video signal is absolute crap and begins to go in and out at around 4/500 years away from me (guestimate) and I've tried all the different channels on the VTx and the monitor with no improvement.

I'm using cheapie mushroom head antennas on the VTx and the monitor.

Can you suggest a way to get a better, cleaner, more powerful video signal?

My iosd mini signal is always strong BTW, no matter the distance.

Thx so much!! Kinda new to all of this...

LightBrigade · Oct 13, 2017

Sorry, here's a hopefully working link to the VTx i have... LINK

J Dot · Oct 13, 2017

Hello
The 4mm patch antenna give you a STRONGER, faster lock to satellites , I did not see extra satellites, only faster and stronger signal.
When I got my first phantom ( p2v ) it would take up to 5 minutes to hook to 6 satellites, then it would rock back and forth from 5 to 6 to 5 to 6, etc changing from GPS mode to ATTI, and back, I HATED IT! ( most I ever saw was 7 ) When I did 4mm upgrade, it locked within seconds to 6-7, back and forth, and would aquire satellites indoors.
Then later added GPS BOOSTER, and BAM went to 11, most I've seen was 13, but not too often, 11 mostly.
Now I've never had a problem! Always squire gps lock and home lock, even in my bedroom! It is crazy! But works!

As for distance,
I gave up when Ittelite antennas came out, p2v and up! Not sure if they make a p2 version?

But
I used cloverleaf first with not much luck, then went circular polarized ( left I think? ) but not 100% left or right ( LHCP OR RHCP )
They were pretty good

Then Diapoles came out they were even better, and you did not have to alter the craft, only Tx.

Then ittelite came in
Single unit for 5.8 Ghz tx and 2.4ghz wifi all on Tx , nothing on bird, went over 4 miles!

You are opposite
2.4 tx, 5.8 wireless.

I'm sure if you search here for antenna options for p2 ( under p2 mods ) might be more help!

I run ittelite on mine ( I fly the most ), others are stock! But t don't need any distance, for hobby and work! ( I build swimming pools, and keep a portfolio or pics and video ( ground and sky )!
( now I think about it, I think they do make a 2.4 ittelite version ) that would be the best bet, or wire the 5.8 one backwards ( does require Tx mod to accomodate the cable style ( smh ) I believe to mini fla connector ( if I remember correctly? Been a while ) lol

J Dot

cneedelman · Oct 13, 2017

LightBrigade said:
Thank you!! I’m getting one right now!

The vendor is called Buzzcam. He sells kits with the 4mm GPS antenna and an insert that shields the antenna from the rest of the electronics inside. I had to carve out a bit of the plastic in the top of the shell to get the thicker antenna to fit.

PMPhantom · Oct 22, 2017

Just did my GPS mod, added a TAOGLAS GPS Antenna... funny thing I noticed is that when I touch the top of my P2 V+ the satellite count goes from "6" to "0". When I take my hand off the top, the Satellite Count goes back up to 6 within a few seconds... check out the video I just made showing the issue. Anyone else having this problem? Also, it is VERY slow to reach 6 satellites initially, but once it gets there, touching the top changes things very quickly. Video here -> http://www.mars4homes.com/GPS-Mod.mp4

J Dot · Oct 22, 2017

I think they all do that,
As I've come across that before!

But you are indoors as well, and a 6 satellite w/ homelock indoors is impressive in itself! I believe this is why GPS is located where it is ( top most position ) with least interference as possible!

Is it slow to pickup outside as well?

J Dot

PMPhantom · Oct 22, 2017

Thank you so much for your response! I am really stressing over this. The GPS Antenna mod seems to have gone OK, but reception was very intermittent at first. I fixed the cable connector and it got better, but then I noticed the "hand" effect. Every time I even touched it the green lights went out. I honestly don't remember it doing that. So of course I thought I screwed up the soldering of the new gps antenna module, or the reattachment of the 2 layers of gray/copper shielding. I took photos before and made 100% sure to put it all back exactly as was. I thought the new GPS antenna mod would be like a miracle. Not sure if outdoors is any better. It takes at least 30 seconds after Battery Power-On to get satellite lock, and it might even take turning on the DJI Vision App and setting WiFi to the Phantom before it gets satellites. Not sure if this is normal either. I thought it previously got satellites without wifi connection?? Not sure, I'm confused since noticing the "Hand" effect. I will experiment outdoors in the morning light. Thx again for your input!!

jason · Oct 22, 2017

The reaction to putting your hand over the GPS module is completely normal.

WIFI has nothing to do with loss of signal since it operates at 2.4GHz and GPS is at 1575.24MGz

N017RW · Oct 22, 2017

If you think about the strength of the GPS signal at the surface this begins to make (even more) sense.

Generally speaking:
The SV's have a 25-26 watt transmitter and a 13dBi antenna This results in about 27dBW or 500W ERP... but they are 21,000km up.

When you factor in the path loss this (~-182 db) your left with about -155dBW.

That's about 3.16e-19 watts, or 0.000000000000000000316 watts!

Another thing to consider is this- snipped from the web:
"You may encounter a slow start if your GPS has been unused for days or weeks, or has been transported a significant distance while turned off. In these cases, the GPS must update its almanac and ephemeris data and then store it in memory."

In the older Phantoms the GPS engine's back-up batttery (actually a super-cap) would fail or discharge between uses and caused delayed lock frequently.

Not sure what the newer Phantom's have for back-up that may have reduced or eliminated this issue currently.

PMPhantom · Oct 22, 2017

Thanks for all the responses... feeling much better. OK, so this morning I turned on my Phantom 2V+ v3 and got only blinking Yellow Led's until I turned on the Remote, then BAM instant Green. So I assume this is also normal behavior. Indoors I get 6 Sat's and outdoors in the backyard I'm getting 8 Sat's.

FYI: I'm new to this and have only had my PV2+ for about a month (purchased on ebay) so slowly but surely I am understanding the process of all this. I have flown it a dozen times so far. I jiggle the switch and do the Compass Calibration dance every single time before I fly, but in testing the new GPS antenna disc, I'm seeing everything in a different light and paying much more attention to what's going on. Never realized that perhaps the green GPS lock was dependent on turning on the RC Controller. I will complete the re-assembly by putting all screws back in place and go flying shortly. Thanks again!!

PMPhantom · Oct 22, 2017

N017RW said:
If you think about the strength of the GPS signal at the surface this begins to make (even more) sense.

Generally speaking:
The SV's have a 25-26 watt transmitter and a 13dBi antenna This results in about 27dBW or 500W ERP... but they are 21,000km up.

When you factor in the path loss this (~-182 db) your left with about -155dBW.

That's about 3.16e-19 watts, or 0.000000000000000000316 watts!

Another thing to consider is this- snipped from the web:
"You may encounter a slow start if your GPS has been unused for days or weeks, or has been transported a significant distance while turned off. In these cases, the GPS must update its almanac and ephemeris data and then store it in memory."

In the older Phantoms the GPS engine's back-up batttery (actually a super-cap) would fail or discharge between uses and caused delayed lock frequently.

Not sure what the newer Phantom's have for back-up that may have reduced or eliminated this issue currently.

WOW!!! Awesome info... I'll investigate the Super Cap idea, maybe I need to replace mine?

N017RW · Oct 22, 2017

You should ALWAYS turn on the controller first, and off last. This is just good form.

This may be less critical with the Spread Spectrum stuff but in the early days with a CW system it was a must or ANYTHING could happen.