I like the concept, anxious to hear the test results and would like to see closeups where the antenna exits airframe. Also, if pointing Sonix antenna down would make much difference with wifi. Not an antenna expert but I did notice when I disassembled the airframe, one of my antenna leads was magnetically attached to a motor case. Wondering if the “antenna bulb” is protecting a coil and what total length we are talking about for the antenna?
That moves the antennas much closer to the GPS. Any noticeable difference in GPS reception?
@JEFFGORDON, I cut bottom case cover edge a little to open cable exit. I am not familiar with antenna not sure what is inside but SV’s are good. .
On other SV before mod, it kept connection to 1.1km until it turns direction. I was able to repeat a few times until it did not return. 
probably pushed battery too much. I want to keep monitoring during critical return path.
@brad112358, SV does not have enough clearance lower side and I let it stand. GPS seems to be ok during this flight. Marker is where it made 180 deg turn.
Hope this helps. I will continue to test.
Satoru
After seeing you antenna relocation earlier today I did the same but with foam tape to test. Although it’s raining all day so testing will be …
@Satoru_Sasaki
I like the look even if it does nothing for performance. I’ll see what I can come up with along those lines.
OK OK . . . couldn’t resist . . . gets style points and is a bit intimidating?
(press fit for easy removal)
UPDATE: Mounting antenna externally produced no noticeable difference in range or function. Moved antenna back to original position.
Curious, Why point them up instead of down? Since 90% of the time…the SV shoudl be above you, wouldn’t that make more sense, and also not cause as much GPS interference?
My thoughts exactly, but thought I’d experiment with relocation anywhere outside the frame.
Next up, I’ll experiment with keeping the sleeve balun inside the frame and just letting the remainder of the antenna hang out the bottom.
Does anyone know what the little bulb/can/tube thing is called and why it is there? I’ve been Googling but cannot find other examples of one.
Google loaded antenna . . . that’s my guess
I built this for the TX but have not tested. I got a short cable with the right connector from a laptop wifi antenna to add instead of the spin on shown in the video. Will be the weekend before I can test.
@lordneeko, Idea to place antenna vertical is to keep equal connection towards all direction horizontally. SV antenna sits horizontally and I am experiencing it tends to lose connection when it makes 180 deg turn, I suspect it is due to antenna directionality. These dipole antenna signal reception is weakest when it points toward tx.
I fly at grass field and it will interfere if placed downward. SV will be a few 100 meter away when connection is critical, upward and downward does not matter much. So far no GPS issue as posted log graph shows.
@JEFFGORDON, very quick! I guess max range will not change, but connection should be more stable at any SV direction, @Dude, curious to see the result of Tx antenna mod! (sorry edited).
Satoru
@Dude . . . watched your video and was inspired by the coil winding around a screw. Since I was working with coax today (new TV) thought I’d give it a go. It did occur to me that the “video dude” went to a lot of trouble to measure-cut-solder the antenna. Since the copper core of coax can be withdrawn and re-inserted in the center nylon core, why not just:
- Cut an oversized length of ready made cable (I had some old stiff RG6)
- remove the copper core
- wind the center 70mm into a coil
- now you can accurately trim one end to 60mm
- trim down the jacket and shielding leaving the fitting undisturbed to accommodate sleeve balun
. . . and I didn’t have any copper tubing on hand so a balun doesn’t show in the pics but easily added after removing copper core . . . a second time - slide 25mm of copper tubing (sleeve balun) over the entire housing and solder the shield to it
- reinsert copper core and trim leaving .25" exposed inside fitting
. . . am I missing something or would this be a lot easier and more precise?
Then I can mount a coax wall plate connector, I have laying around, in the transmitter to screw the whole assembly to.
@lordneeko . . . did some research and the “little bulb/can/tube thing” is apparently a Sleeve Balun.
But after looking at the diagram, it appears the “video dude” soldered the shield to the opposite end of the balun. Wonder which is correct? Maybe application for tx is different than rx?
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ok cool…but what is the purpose? Does it work to try to block out signals that aren’t within the tuned 1/4 wavelength the tube is cut to? That’s my assumption based on a tiny bit of googling of its purpose.
In other words, if I just go and grab a 2.4Ghz antenna online and plug it in, am I going to get worse problems?
Unless we have an ‘antenna dude’ chime in we won’t know until we try. 
Take a look here, about 12 posts down:
https://diydrones.com/m/blogpost?id=705844%3ABlogPost%3A1668508&maxDate=2014-05-29T14%3A12%3A05.716Z
I tried a simple antenna the other day . Via removing a Ariel from a old modem and just cutting to a length of 100mm. then stripped 25mm outer casing off and rolled back the outter coax. So I had 50mm by 25mm by 25mm.
So was similar to this…
Didn’t work, it lost signal alot and the range was shy of 100feet. Now could of been I didn’t have right desired length I’m not sure. But have now gone back to the original.
This might be a discussion to have over on RCgroups.com instead. This forum is mainly for discussing software, which is probably why we aren’t getting much involvement from anyone but us losers. Over on RCGroups, we might find a thread that talks about antennas. There is a SV2450 thread over there too…but mostly just the same people in there lol.
https://www.rcgroups.com/forums/showthread.php?2947267-Sky-Viper-2450GPS-full-FPV-GPS-Arducopter-QUAD-for-about-150
I would love if someone came up with a viable MOD for the controller, to mount a 7" tablet to.
Like this
