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7-Element Yagi Range Extender 2.4 Ghz for MM (CE)

aeropic

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Hi Quadbee, thanks for sharing your design !
I get 2 questions:
- how important is the accuracy ? You give here dimension down to 1/100mm which is, at least for me, not possible to manufacture... Is rounding to 1/10 enough for 2,4GHz?
- distance of the elements are given relatively to the middle of the mini antenna. Is it the center of the plastic case or the center of the antenna PCB ?
 

Quadbee

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I would say the more precise the better. My digital caliper is able to measure 1/100 mm but I have to admit that its hard to trim the rods so exact. For 2.4 GHz I think 1/10 mm is enough.

The distances are in relation to the middle of the plasic case. The board with the antenna is placed quite good centered in it and the antenna is divided in one half of the dipol on each side, so the middle is in my opinion the best virtual reference point. The importance of the distances is not so high as the element lenghts.
 
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sw3De

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There is enough transmission power to feed any antenna. ;) It all depends on the correct dimensions.

Here are the parameters for my 7-Element standard version (2.4G) build with 3 mm alu rods.

Distances from the middle of the original antenna:
R=-24 mm
D1=10 mm
D2=32 mm
D3=58 mm
D4=89 mm
D5=123 mm

Lenghts of the elements:
R: 57.93 mm
D1: 51.46 mm
D2: 48.99 mm
D3: 48.26 mm
D4: 48.76 mm
D5: 49.43 mm

Happy Longranging :cool:
Thanks!
I have a 3D printer so this was the measurements I was looking for.

I have some questions if I may;
-How much of a difference will the material of the rods make in reality, say between aluminium, copper and steel?
-Does it matter if you use pipes (hollow) instead of rods (solid)?

*edit
-Does it have to be 3mm rods? Would it work with i.e 2.8 or 3.2mm
 
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WooZie

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i used aluminium pipe of 3mm diameter and works very well, both antennas 5.8 and 2.4. In 5.8 i got 1km and 2.4 - 3km without any glitch of video transmission, it was too windy and i was afraid because the drone had to come back against the wind, but i am pretty sure i could go at least 3.5km
 
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Quadbee

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Thanks!
I have a 3D printer so this was the measurements I was looking for.

I have some questions if I may;
-How much of a difference will the material of the rods make in reality, say between aluminium, copper and steel?
-Does it matter if you use pipes (hollow) instead of rods (solid)?
*edit
-Does it have to be 3mm rods? Would it work with i.e 2.8 or 3.2mm
Aluminium or copper doesn´t make a big difference. Copper is a little bit better but only if its not oxidized, which goes fast in a few weeks. Steel is much worse and for this purpose not a good choice. Better would be silver but I guess nobody would like to pay for that ;)

Pipes would be no problem because RF travels only on the outside of a conductor (skin effect).

The diameter definetely matters. But 0.2 mm difference is not so dramatic. I think you can give it a try.
 
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WooZie

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i have tried before with aluminium 3.2 diameter and did not work, after i found alu of 3mm diameter i put them and it worked
 

Limburg1

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AE2B5989-43BA-4F5F-ABD4-1393E2ED0B81.jpeg 641C752D-7C3C-4C8D-918F-7EFC4E895E69.jpeg Thanks Quadbee for the calculations, made this improvised version and i must say i’m impressed! CE version here btw B4538841-628C-463B-8721-69CB76ECF2BB.png
 
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Limburg1

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Hope to test it this afternoon. Anybody thoughts on this? Im tryin to understand this whole antenna thing, as a welder with some electric knowledge as well this is a new thing to me so every comment is appreciated. I also have made a directional helical antenna but im still not sure if this works due to circular polarization, while i guess linear on the quad. If anyone could confirm this or correct me would be cool to! 512B5953-A9D6-4E16-A0EF-4E60A1B98213.png
image.jpg
 

Jumper Boy

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[QUOTE = "Essilor, publicación: 1098171, miembro: 132468"]
Ok, todo esta listo! :) ¡el fin de semana comienzan las pruebas!
View attachment 112788
[/CITAR]
Socio, ¿tienes el archivo STL para poder imprimirlos? Gracias por adelantado
 

Jumper Boy

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Hey Guys,

I´ve developed two new Range Extender 7-Element Yagi versions for the Mavic Mini (CE) on 2.4 Ghz. They are computer optimized with 4NEC2 an antenna modeling software. It took me quite long to reverse engineer the rf-parameters of the original dipols of the remote, because they use dual band antennas with shortend dipols and capacitors at the end. The standard Range Extender Design for 2.4 Ghz with the 5-Element version which goes around the last months is not bad but hasn´t the best SWR ratio, so I decided to do better ;)

The standard 7-Element version has about 12.4 dBi gain with a length of approx 15 cm and the long version 13.4 dBi with a length of 20 cm. I´ve done some measurements with the RF Power Meter V2 from ImmersionRC and the values seem to be realistic. Attached you find photos of the antennas and the radiation characteristics. My first tests were very promising but I´m living in a very dense populated area in Germany and I have to find a good place at first where I really could fly out the limits.

Cheers
Partner do you have the STL file to be able to print them? Thanks in advance
 
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