Do they actually work ?
I got quite a few errors while flying this evening and couldn't help but wondering if an extender would do any good
RC  even lost connection while still in view

Pros & Cons .... ?
Any ideas which to get if ........

What bird are you flying? What are you using for a screen? What OS if a tablet?

Phantom 4
iPhone 6s+
IOS 11.2.5.

Range extenders do work yes but make sure you buy good quality ones.
When you look at the mirror surface front on there should be no ripples at all.
Once fitted over antenna again looking front on you should see the antenna reflection magnified in the mirror surface.
Warning these extenders are very direct you need to face the antenna directly at the drone for them to work correctly if you face away from the drone you can easily loose signal.
I would not recommend these to novice pilots

Im a novice myself
Only had it a week. (not my first drone though )
I just tried flying out to about a 1/2 mile and lost signal again
Ive tried reorienting the antenna on the RC  but that didnt help either
Thought an extender may do the trick.
Why am I not getting the full distance or even close to it

HI, many reasons why you are not getting the range, objects in the way such as 1 tree is enough to do it, not only you who must keep visual line of sight  but so must the controller, with the controller in the horizontal position in your hands,  the antennae must be pointing to the sky, the wind, sunny or cloudy, fog, humidity, radio interference, and more factors can impede distance, you said you got half a mile, damn, think ya self lucky ya not in CE country lol joking aside. Lets ask, where did you send her off for a distance test? was there anything in the way,  maybe a shed, barn, blade of grass, bu truthful now, we cannot help other wise ;) what sort of day was it? overcast, cloudy, mostly cloudy, partly clo... Sunny? Do you know what the humidity was like? (where are you, i can check on the latter) was it windy, are you near any TV or Radio transmitter and how high was you flying. let me give you my findings...

OK i have the Phantom 4 Pro, i was struggling to get much over 500m (im in CE so less power then FCC) I bought a parabolic antennae booster and managed to double the distance, that was great but i wanted my AC to fly what it says it can on the box 3500m. I did however update the firmware, to the latest beta and since then have been able to get close;
please note the different conditions

800m, ac @ 100m height, flat countryside, foggy (100m visibility) no wind, no radio interference
2313m, ac @ 100m height, flat countryside, partly cloudy, 10mph wind, no radio interference
3116m, ac @ 100m height, flat countryside, sunny, no wind,  no radio interference

Each flight was from the exact same spot +/- 1ft, and sent off in the same direction, so, if you go by the above, a sunny, cloudless day with very little wind is the better time to do a distance test, all flights were above 90% humidity as they were all 1st thing in the morning, perhaps i could squeeze a bit more by doing a midday flight more chance of the humidity being much lower??? another day

Just remember, we are in the real world, what it says on paper is no doubt work out mathmatically and not a tested figure, still, we should be somewhere clse even without the need for the parabolic, alas this is not the case.....

As it turns out I did get quite further out when I flew thei other direction
After your post I realised there were quite a lot of trees between myself and my intended flight plan

Uncle T Posted at 2018-1-31 22:15
As it turns out I did get quite further out when I flew thei other direction
After your post I realised there were quite a lot of trees between myself and my intended flight plan

Aloha T,

     Look at this thread.  There is a video and a number of photos and information on parabolics.

https://forum.dji.com/thread-60563-1-1.html

I have also noticed that if I fly in the jungle after a recent rain (almost all the time) my penetration is less than when I fly after those times when it has not rained for a day or two.  But, I doubt you will be flying in a wet jungle any time soon.

     Hope this helps!

Aloha and Drone On!

They don't work. Got a parabolic one for my Mavic 2 Zoom, just waste of money

A range extender can be anything that extends range.  

In this case, the OP is asking about Parabolic Deflectors also known as Windsurfers - specifically - and the thread should be titled as such.  

They work if you buy the right one and it's installed correctly.  Otherwise, it may not help at all or it may even make things worse.  

I have a dji phantom 3 standard drone and fitted a WiFi extender it flys about about 20 meters and then says it’s lost rc connection and returns to home. Is there anybody that can help or give me advice on what to do to fix it