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Xiaomi WIFI repeater external antennas mod

raulvolador

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:D No ghost town at all. It's merely a growing industrial park still unfinished. We use to call them "polígono industrial" I don't know english translation. It was nice that empty road were wind oriented.
 
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Ansia

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:D No ghost town at all. It's merely a growing industrial park still unfinished. We use to call them "polígono industrial" I don't know english translation. It was nice that empty road were wind oriented.
Next time I visit Spain, I want to visit one of these ghosts towns. They are rather intriguing.
 

ph2t

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Great work Raul! :) I am humbled by your reference to my work on this.
Cheers mate!
Have a beer on me!
ph2t.
 

asoerjana

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Here it's full 619 meters test video. This way you could see scary moments due bad video signal. You have to get over when you want to reach limits ;)

Notice strong wind day. I flew againts wind direction, that way it helps me coming back to the takeoff point.

I flew over a empty street about 500 meters long. It helped me be oriented when video quality went bad.

enjoy.
Awesomeeeeeee!!!!! Great work!!!
 

raulvolador

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I succesfully tested Xiaomi Extender external antennas mod. On a test flight I achieved the maximum range so far. I got 728 meters. See here:

 
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DinoBaldi

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I'm following your steps with this mod:

2019-02-11 12.14.43.jpg

I've found these 9db antenna, and after a brutal extraction of Xiaomi Extender...

2019-02-11 12.14.56.jpg

I add an old and cheap powerbank (1A max output, 2200 mAh.).
I can recharge it easy:

2019-02-11 12.14.50.jpg

But now the hardest part is coming:
- desoldering old internal antennas
- strip the very small new antennas cables
- soldering them to the board

I'll keep you tuned :)
 

Guorium

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I'm following your steps with this mod:

View attachment 3158

I've found these 9db antenna, and after a brutal extraction of Xiaomi Extender...

View attachment 3159

I add an old and cheap powerbank (1A max output, 2200 mAh.).
I can recharge it easy:

View attachment 3160

But now the hardest part is coming:
- desoldering old internal antennas
- strip the very small new antennas cables
- soldering them to the board

I'll keep you tuned :)
Make some parabolic reflectors for those too?
 

ph2t

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raulvolador

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I'm following your steps with this mod:
...
But now the hardest part is coming:
- desoldering old internal antennas
- strip the very small new antennas cables
- soldering them to the board

I'll keep you tuned :)
Good work !

I recommend you using good soldering iron, with very thin tip, because there is little space to work.

All the best and share your results.

Raul.
 

DinoBaldi

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Make some parabolic reflectors for those too?
I'm exploring this idea, but i don't know very well how to proceed, so:
1. test with wifi extender with standard antennas
2. test with wifi extender with antennas mod 9db in vertical position
3. test with simple plain reflector

corner-reflector-antenna.jpg
I have to calculate S the right distance of the antennas from the corner of the two plain panels.
I have also to calculate the right distance from antenna to antenna. It seems closer than possible.
I'm looking on the web but is not so easy to find the answer. Maybe here there are some engineers that can help :)

Alfa is the angle. Getting started from 90°, I will check it better solution on the field.
L and H are the dimensions of the panels. Considering that the 9db antenna are 39 cm long,
it will be really large !

That could be a problem on windy days, maybe I have to make them strong and put some weight on my photograpic tripod.

A parabolic reflector could be more complex...
 

bmelody

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The antenna design you are looking at is called a corner reflector antenna. They are a high gain antenna, very directional and easy to build. Be prepared for a very narrow beam width.

The driven element is a simple dipole. The driven element could be as small as 1/10 of a wavelength but because the frequency (2.4 GHz) is so high I would use a full 1/2 wave.To determine its length use this formula; 468/F MHz = 468/2400 = 1/2 wave in feet = 0.195' or 2.34" total length. 1.17" per section. You could use a piece of single sided G10 PC board to make the element. The spacing between the elements should be kept close (1/10") but is not critical. Attach the center of the coax to the top element and the shield of the coax to the lower element. Space it 1/2 wavelength form the back fold of the reflector. Center the dipole between the 2 sides.

I'm not so sure would go through all the trouble to build a 9 dB gain corner reflector when I could use a 9 dB gain omni directional vertical rubber duck antenna. The corner reflector will give you more distance due to focusing the energy in one direction but....... Use 2 rubber duck antennas and take advantage of the diversity that is built in the WiFi repeater.

Check out this video on a corner reflector:
 
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DinoBaldi

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Many thanks bmelody,
your explanation are better than anything i could find on web.

Meanwhile, with the help of a friend really better than me with the solder, I'm ready to the
long distance test with double vertical rubber 9db antennas:

2019-02-13 12.58.17.jpg

and the back:

2019-02-13 12.58.25.jpg

Now I'm recharging the batteries !
I'll fly soon.
 

bmelody

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No question about it, the large circle is the ground.

One thing to be concerned about is preparing the antenna cable's soldered end. You are working with microwave frequencies and the length of cable that sticks out past the end of the shield can cause problems if it is too long and must be kept as short s possible. You have to be careful not to melt the dielectric by getting the shield or center too hot while soldering causing the center conductor to short out to the shield. This is very easy to do if the dielectric is poly or some other soft material. It is possible the coax cable may be made from Teflon witch eliminates the melting problem. It is best to solder the shield of the coax directly to the ground pads without adding any additional wire. Prepare the end of the cable as shown below and you should not have any problems

Tello ant cable.JPG
 

bmelody

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Oh yes..... Microwave, where amplifiers oscillate and oscillators won't! Gobs of fun.
 

raulvolador

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Hi all,

After lot of test with my Xiaomi External antennas mod I have a final veredict, and it's not good... :(

I spend an hour, four flights into a face to face test Stock Xiaomi Repeater vs Modded external antennas Xiaomi.

Test did into residential area about 15 ones 2.4ghz networks around, so moderate / heavy interference.

My modded external antennas performed quite similar to stock Xiaomi (about 130 meters far away). Even worse image quality.

xiaomi mod not recomended.jpg

I can't recommend my external antennas mod anymore. Instead I recommend you new WIFI+S Range Extender. I got excellent results, about double range. See here:

WIFI+S Range Extender vs Xiami WIFI Repeater

All the best.

Raul.
 

ItaloRC

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[QUOTE = "Guorium, postagem: 17246, membro: 5775"]
bem, isso é um caminho:sorrateiro:
[/CITAR]
Mano sou Br tbm. Quanto de distância você atingiu ?
 

Guorium

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Hi all,

After lot of test with my Xiaomi External antennas mod I have a final veredict, and it's not good... :(

I spend an hour, four flights into a face to face test Stock Xiaomi Repeater vs Modded external antennas Xiaomi.

Test did into residential area about 15 ones 2.4ghz networks around, so moderate / heavy interference.

My modded external antennas performed quite similar to stock Xiaomi (about 130 meters far away). Even worse image quality.

View attachment 3277

I can't recommend my external antennas mod anymore. Instead I recommend you new WIFI+S Range Extender. I got excellent results, about double range. See here:

WIFI+S Range Extender vs Xiami WIFI Repeater

All the best.

Raul.
Ron on tello fb group got 706m off of a stock xiaomi in the country on TelloFPV. He is in US. Posted video. It confirmed that your mod probably isn’t that helpful.
 

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