PDA

View Full Version : Virevent & Turbine advanced CP antennas tutorial.



HugeOne
7th September 2011, 11:31 PM
I designed these two antennas for FPV purpose. They stress on axial ratio (0.9 or better) for maximum multipath rejection.

Tutorial (http://www.truerc.net/images/tutorials/Vireventtutor.pdf)

They can also be purchased from www.truerc.net/canada (http://www.truerc.net/canada) among others.

-Hugo

IBCrazy
8th September 2011, 09:21 AM
One of these days you and I need to finish the designs we talked about...

For those who might be reading this, Hugo and I have decided to start designing together so keep an eye out for the products of our joint efforts.

-Alex

volto
8th September 2011, 11:22 AM
Awesome tutorials, thanks Hugo! Any chance you can include dimensions and angles for the fan antenna as well? Also, will 0.035" (0.889 mm) MIG wire work for all frequencies, or will I have to slightly change the dimensions? I noticed you said to use 0.8 for all but 5.8ghz, so is this wire not going to work for 5.8ghz antennas (need thinner wire)? I have seen people build 5.8 CL and SPW from big fat romex type copper wire.

I'm glad the two of you are cooperating, that is awesome! Two geniuses working for a common goal, can't wait to see what you come up with.

whakahere
8th September 2011, 11:54 AM
nice. I am going to give one a go. Question, since I have a cp and spw where would you think this would be better? On the rx or tx --- on 5.8ghz


Looking forward to your other designs guys.

mrdlg2u
8th September 2011, 12:44 PM
I have built a bunch of antennas thanks to tutorials like these. I even bought a hand held spectrum analyzer to check my work.

What do you think the effect of using something like expanding foam to in case the antennas?
or may be just fill the center with the expanding foam, not covering the outer surface of the wire.

I don't want to mess with any of my antennas until I get some thoughts on the idea... LOL

Later,
Gundy

HugeOne
8th September 2011, 10:42 PM
Yes, me an Alex are working together, be prepared for some wicked mad scientists RF devices :)P

I'll have to make a chart for the Fan and its little sister the Windmill. In fact, by way things look, they may well phase out the virevent & turbine.

I heard rumor that a CL on the Tx and a turbine on the Rx is a killer combo.

Encasing the antennas in foam will shift frequency downward by an unknown %.

-Hugo

volto
8th September 2011, 11:27 PM
Sweet, I want to build a fan antenna because it's only 3 elements, simple to build and from the radiation pattern looks like a winner.

What about my 0.89 mm mig wire, will it work with the given dimensions or should I add or subtract some length, or look for some different wire?

Thanks!
Jerrod

HugeOne
9th September 2011, 12:18 AM
Jerrod,

The 3 element is called the "windmill", 5 elements is the "fan". I given them different names because making a virevent with 5 or 8 elements doesn't work, pitch angle and sizes are different.

So to clear confusion:
3 blades: Windmill >> Sweet Tx antenna
4 blades: Virevent >> First born.
5 blades: Fan >> Sweet Rx antenna
8 blades: Turbine >> Mother of Rx antenna

For your 0.89mm wire add 1%.

-Hugo

volto
9th September 2011, 02:13 AM
I thought I might have gotten those two confused.

Thanks for clearing that up about the wire.

MR_Crash
27th October 2011, 02:31 PM
Have the dimensions for the fan antenna been released yet?

I just finished up this 5.8 turbine. How's it look?

HugeOne
27th October 2011, 02:43 PM
It look awesome, 5.8ghz turbines are real jewels.

I haven't made the the tutorials for the 3 & 5 lobes units, Alex keep me busy simulating and building his crazy ideas ;)

-Hugo

whakahere
27th October 2011, 03:21 PM
I don't have any .6mm wire. what would the measurements to build a Turbine using .6mm wire?

I am also using silver coated copper wire. does that matter?

HugeOne
27th October 2011, 11:38 PM
I don't have any .6mm wire. what would the measurements to build a Turbine using .6mm wire?

I am also using silver coated copper wire. does that matter?

You mean you don't have 0.5mm and need sizes for 0.6mm??

volto
28th October 2011, 12:37 AM
I would think silver coated copper wire will be a lot more malleable and thus not hold it's shape as well as MIG wire (copper coated steel).

M'ck'y
28th October 2011, 01:46 AM
what do we need on the 2.4ghz receiver's end for 15km :)

whakahere
28th October 2011, 08:00 AM
You mean you don't have 0.5mm and need sizes for 0.6mm??

yes, I don't have 0.5 wire.


I would think silver coated copper wire will be a lot more malleable and thus not hold it's shape as well as MIG wire (copper coated steel).

too true but since I build 5.8ghz antennas they are small anyway.

edit: them smash up good. Just finished some crazy inbetween trees and rocks flying. The crash smashed it up pretty good. I bent it back but will have to build another one :) What combo do you think is best for tree flying? 3 leaf and the the turbine?

HugeOne
28th October 2011, 12:25 PM
Add 1.7% to the dimensions. A heard good thing about a cloverleaf on the Tx and a turbine on the Rx.


what do we need on the 2.4ghz receiver's end for 15km :)

A 12T helical.

-Hugo

Greg
28th October 2011, 12:40 PM
I think I am going to give this another shot. My first attempt had some seriously bad results (4.5swr).

Can you guys think of a way I can cad and cnc a jig to help me make these? PM if necessary ..i am not attempting to resell them or give out any info.

culexus
17th December 2011, 09:04 PM
I love the design of Turbine antenna, hope to make some 5.8ghz when I get ready with my next ritewing build.

Is it possible to get a european guide in metric ? Im not used to work with inches :)
And I don`t like to recalculate from inch to mm when it`s so precise.

One question, what is up and down on antennas like this? dose it matter if you mount it sideways or upside down?
I guess up is when your antenna cable is vertical and the active antenna part is on top :)
The reason I ask is than I will have one helical and one Turbine on my tracker ground station and the best way to mount the Turbine antenna will be upside down .

HugeOne
17th December 2011, 10:18 PM
Upside down will work well too, however the null on top will be bigger because of the coax and others thing that may be over it.
You can multiply by 25.4, you'll be as precise.

-Hugo

Martinba77
11th March 2012, 07:07 AM
Hi Hugo great tutorial thanks for posting this awesome job!

Do you think that theres some issue if one just try to build this design with UT141 (im on 5.8GHz) and just keep the center conductor as "D"?

I found some issues while tuning but apart from this there is something else that may shouldnt work using semi-rigid coax?

Thanks in advance!

Martin

HugeOne
11th March 2012, 08:47 AM
I don't see any problem apart that the bigger center conductor will shift frequency up a bit.

-Hugo

Martinba77
11th March 2012, 03:22 PM
Thanks for your reply Hugo.

Martin

ecampos
27th March 2012, 07:19 AM
Here are some pics of my first build of this antenna including also pics of some steps of the building process. It's actually a lot easier to build precisely and get good SWR than a cloverleaf/SPW; i got around 1:25 - 1:3 SWR, not bad for a first build ! My question is, what is the maximum effective gain for it ? Also, i would like to build a turbine, but i can't find the base wires angles... Thanks :)

HugeOne
27th March 2012, 08:28 AM
Nice built ecampos, turbine angle is 45deg. Gain is in the approx 1.2db.

-Hugo

volto
27th March 2012, 12:53 PM
Here are some pics of my first build of this antenna including also pics of some steps of the building process. It's actually a lot easier to build precisely and get good SWR than a cloverleaf/SPW; i got around 1:25 - 1:3 SWR, not bad for a first build ! My question is, what is the maximum effective gain for it ? Also, i would like to build a turbine, but i can't find the base wires angles... Thanks :)

Nice build, but with that level of precision, how would you possibly get worse SWR with a cloverleaf?

ecampos
27th March 2012, 04:15 PM
Nice build, but with that level of precision, how would you possibly get worse SWR with a cloverleaf?

Humm... don't know exactly... Maybe i have some difficulties building that round side of cloverleaf/SPW's lobes. I prefer playing with straigth wires :) I'll give another try on the cloverleaf tonight...

ecampos
5th April 2012, 12:03 AM
So, just built my own turbine (1280mhz) and got almost 1.1 SWR !! Thanx again Hugo for this great design :) I'm hopping if you have the dimensions table for a Windmill using the old build method ? (the one from the virevent/turbine tutorial pdf on the first post of this thread, not the one using a single wire for each leg). Here's some pics of the building process:

http://img832.imageshack.us/img832/29/1000511w.th.jpg (http://img832.imageshack.us/i/1000511w.jpg/)http://img141.imageshack.us/img141/2627/1000516j.th.jpg (http://img141.imageshack.us/i/1000516j.jpg/)http://img20.imageshack.us/img20/697/1000517rl.th.jpg (http://img20.imageshack.us/i/1000517rl.jpg/)http://img685.imageshack.us/img685/8659/1000520h.th.jpg (http://img685.imageshack.us/i/1000520h.jpg/)http://img819.imageshack.us/img819/8361/1000525u.th.jpg (http://img819.imageshack.us/i/1000525u.jpg/)http://img684.imageshack.us/img684/1566/1000527s.th.jpg (http://img684.imageshack.us/i/1000527s.jpg/)http://img444.imageshack.us/img444/7818/1000534o.th.jpg (http://img444.imageshack.us/i/1000534o.jpg/)http://img213.imageshack.us/img213/1391/1000537c.th.jpg (http://img213.imageshack.us/i/1000537c.jpg/)http://img35.imageshack.us/img35/4644/1000550s.th.jpg (http://img35.imageshack.us/i/1000550s.jpg/)http://img718.imageshack.us/img718/8099/1000556z.th.jpg (http://img718.imageshack.us/i/1000556z.jpg/)http://img20.imageshack.us/img20/7062/1000560m.th.jpg (http://img20.imageshack.us/i/1000560m.jpg/)http://img687.imageshack.us/img687/4816/1000563zn.th.jpg (http://img687.imageshack.us/i/1000563zn.jpg/)http://img403.imageshack.us/img403/729/1000571y.th.jpg (http://img403.imageshack.us/i/1000571y.jpg/)http://img23.imageshack.us/img23/7230/1000584v.th.jpg (http://img23.imageshack.us/i/1000584v.jpg/)http://img402.imageshack.us/img402/5059/1000580d.th.jpg (http://img402.imageshack.us/i/1000580d.jpg/)

volto
5th April 2012, 01:34 AM
My mind is blown at how strait you get those wires. How in the hell do you get them that strait? Nice work.

ecampos
5th April 2012, 07:18 AM
Simple, twist them ! Here's my method: I attach one side of a wire to a vice and the other to a low speed drill and i twist the wire while gently pulling the drill towards me (do not apply to much power, as it will thin the wire) After a couple of turns, the wire gets straight... Then, while maintaining the tension on the wire, just cut it and you get a perfectly straight antenna wire ready to get cut and trimmed :)


My mind is blown at how strait you get those wires. How in the hell do you get them that strait? Nice work.

HugeOne
5th April 2012, 08:12 AM
Nice work ecampos! I'll look at what I can do about the tutorial. My fear is to make more confusion.

-Hugo

ecampos
8th April 2012, 11:12 PM
Nice work ecampos! I'll look at what I can do about the tutorial. My fear is to make more confusion.

-Hugo

In this case, can you just PM me the dimensions (1280mhz) ? Thanks a lot ! :D

Maineiack
24th May 2012, 03:33 PM
heres my go at the Virevent and Turbine,
needs a real cable with connector, and the adjustment, but im bored and have a need to solder stuff up,,lol,,
going after the 5.8 next,,,or the "New" fan,,just saw that,,,

THANK YOU HugeOne
john

Maineiack
4th July 2012, 09:40 PM
so i just finished building the 5.8 Turbine
have to clean it up and
dont have the RG316 cable yet so i winged it,
had to make a jig for those 16-dinky tiny wires

YOU DESERVE EVERY PENNY YOU GET
selling these small things,

man there tough to build
id rather play with the crosshairs

THANK YOU very much for sharing the build

HugeOne
5th July 2012, 08:31 AM
Good work there! Yes, they are though to build at 5.8Ghz, but definitely worth it.

-Hugo

Maineiack
7th July 2012, 12:28 PM
so i did it over,

90degs out
69% humidity
71F Dewpoint

set my 600 TX/CL
in window in front of a fan
walked 300Ft started rolling like a bad TV
this was slightly behind a hill and a couple of trees in the way
in the middle of the city

so
300ft X (6Db X2 attenuators) 12 =3600Ft = .68 of a mile

is this an acceptable range?
or do i need to do some adjusting?

thanks

HugeOne
7th July 2012, 01:14 PM
Range is something too hard to guess. Move your attenuators to thetx side and star over, you will have a better approximate.

Hugo

Maineiack
7th July 2012, 02:11 PM
switched it around
700ft x12=8400=1.59 mile
ran out of room
thats with a hill and a line of trees blocking

hot wet and muggy

HugeOne
7th July 2012, 03:47 PM
1.6Miles "omni" with a bad LOS, that seem good.

-Hugo

Maineiack
7th July 2012, 03:49 PM
thank you

Nelapaty
11th December 2012, 06:32 PM
Hugo could you give dimensions for 1258Mhz please..

HugeOne
12th December 2012, 12:23 AM
For 1258 use 1280, even if narrow band my antenna still cover 1258 nicely. If you feel perfectionist you can multiply by 1280/1258.

Hugo

Nelapaty
12th December 2012, 08:10 AM
Hugo is it multiply or divide?

1280x1258 = 1610240
1280/1258 = 1.0174 add it to the given dimensions

Im confused:confused:

Dimensions of Turbine
1280mhz

A 4,291
B 3,269
C 3,069
D 0,978
E 1,382

I will pm you on rcgroups..Thanks

HugeOne
12th December 2012, 10:22 AM
You multiply by the result of the division ;)

Dimensions * (1280/1258)
example:

A. 4.291 * (1280/1258)
= 4.291 * 1.0175
= 4.366

-Hugo

Nelapaty
12th December 2012, 10:37 AM
Super Thanks:)

slowjet
23rd December 2012, 11:37 PM
what happens if you build these upside down? i just made a 1280 windmill and realized that i put the long arm of the element on the top and the short on the bottom connecting to the ground... :(

HugeOne
24th December 2012, 02:23 AM
I don't think it'll work, you may have good SWR, but circularity won't be there.

-Hugo

slowjet
24th December 2012, 03:44 AM
Thanks hugo. I'll rebuild it then. The Fan came out good though! :)

TexasAggie
30th December 2012, 12:33 AM
It looks to me like this technique is slightly simpler to get precise compared to your newer method. Could you list the dimensions for the older technique for a 1280 MHz windmill and fan?

TexasAggie
31st December 2012, 02:54 PM
I went ahead and reverse-engineered the numbers. Correct me if I'm wrong:
Windmill
<table border="0" cellpadding="0" cellspacing="0" width="128"><colgroup><col style="width:48pt" span="2" width="64"> </colgroup><tbody><tr style="height:15.0pt" height="20"> <td style="height:15.0pt;width:48pt" height="20" width="64">A</td> <td style="width:48pt" align="right" width="64">4.732</td> </tr> <tr style="height:15.0pt" height="20"> <td style="height:15.0pt" height="20">B</td> <td align="right">3.375</td> </tr> <tr style="height:15.0pt" height="20"> <td style="height:15.0pt" height="20">C</td> <td align="right">3.175</td> </tr> <tr style="height:15.0pt" height="20"> <td style="height:15.0pt" height="20">D</td> <td align="right">1.087</td> </tr> <tr style="height:15.0pt" height="20"> <td style="height:15.0pt" height="20">E</td> <td align="right">2.553</td> </tr> </tbody></table>

Fan
<table border="0" cellpadding="0" cellspacing="0" width="128"><colgroup><col style="width:48pt" span="2" width="64"> </colgroup><tbody><tr style="height:15.0pt" height="20"> <td style="height:15.0pt;width:48pt" height="20" width="64">A</td> <td style="width:48pt" align="right" width="64">4.428</td> </tr> <tr style="height:15.0pt" height="20"> <td style="height:15.0pt" height="20">B</td> <td align="right">3.224</td> </tr> <tr style="height:15.0pt" height="20"> <td style="height:15.0pt" height="20">C</td> <td align="right">3.024</td> </tr> <tr style="height:15.0pt" height="20"> <td style="height:15.0pt" height="20">D</td> <td align="right">0.991</td> </tr> <tr style="height:15.0pt" height="20"> <td style="height:15.0pt" height="20">E</td> <td align="right">1.809</td> </tr> </tbody></table>

HugeOne
3rd January 2013, 12:42 AM
The first tut. was a while ago, I'll have to sit and look.

-Hugo

bignose13
27th January 2013, 03:50 AM
In the tutorial you mention using .6 wire for the 5.8 virevent, thing is I only have .5, would this make that much of a difference in performance
If so could you give me the updated measurement please
I posted this in RCG as well, sorry for being a pain but want to get started asap
Thanks s lot,
Simon

HugeOne
27th January 2013, 08:54 AM
That will shift frequency upward by 1% or so, not a big worry.

Hugo

bignose13
27th January 2013, 03:31 PM
Thanks Hugo
Appreciate it
Simon

Martinba77
30th January 2013, 04:14 PM
Hey guys!

At least I decided to build a Virevent antenna for my 5.8GHz A/V system!
I've follow the Hugo tutorial from start to finish, I have used .6mm copper wire.

The dimensions in mm are :

A = 26.80
B = 23.15
C = 18.05
D = 6.00
E = 12.00

Im looking forward for the weather to improve to give this antenna a go in flight.

Great thanks Hugo for share your work and for the easy to follow tutorial!:D

Left some pictures attached, need to clean some the soldering with the file and solder the connector into the coaxial cable.

Thanks again Hugo!!

Martin

HugeOne
31st January 2013, 03:44 PM
Really nice work there!

-Hugo

Martinba77
1st February 2013, 06:50 AM
Thanks Hugo!

Can't wait to test it! I keep looking at the Virevent antenna in my hands, it's just so beatifull designed!

Martin

Martinba77
8th February 2013, 05:16 PM
Hey guys!

Hugo, I have had great sucess with the Virevent antenna in-flight!
While this was my very first build for this design, the results were very good. Thanks for your dedication!

Have some video later.

Post the video on the "Video Link footage ONLY" thread here : http://youtu.be/12uRlIzz_HI

Martin

mirb
14th March 2013, 11:07 PM
Hi Hugo, can i ask to you for 5.8 turbine dimensions in the format: arms, 1st bend, 2nd bend, center? Have you already tested a "stacked turbine"? Which gain and axial ratio may it have?

thanks.
Mirco.

HugeOne
18th March 2013, 08:58 AM
Mirco,

0.5mm wire
<table border="0" cellpadding="0" cellspacing="0" width="160"><colgroup><col style="width:60pt" span="2" width="80"> </colgroup><tbody><tr style="height:12.75pt" height="17"> <td class="xl24" style="height:12.75pt;width:60pt" height="17" width="80">Arms</td> <td class="xl25" style="width:60pt" align="right" width="80">1,730</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl27" style="height:12.75pt" height="17">1rt bend</td> <td class="xl26" align="right">1,077</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl28" style="height:12.75pt" height="17">2nd bend</td> <td class="xl29" align="right">0,743</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl30" style="height:12.75pt" height="17">Center</td> <td class="xl31" align="right">0,229</td> </tr> <tr style="height:13.5pt" height="18"> <td class="xl32" style="height:13.5pt" height="18">pitch</td> <td class="xl33" align="right">45
</td> </tr> </tbody></table>

mirb
18th March 2013, 09:13 AM
thanks, Hugo; for a 1200mhz antenna can i use the 1180 dimensions or is better scaling to the right frequency?

HugeOne
18th March 2013, 10:07 AM
Use 1180, +/-20MHz is in within the tolerance than one can achieve anyway.

-Hugo

majkl
30th March 2013, 09:37 AM
Any adverse effect if using a 0.8mm steel wire for 1300Mhz? How much % should I take/add to the measurments?
Thanks

HugeOne
30th March 2013, 10:53 AM
It is already based around 0.8mm wire, nothing to change.

Hugo

majkl
30th March 2013, 10:57 AM
Oh ok. I ask because the dimensions listed on the last page noted a 0.5mm for the turbine.

HugeOne
30th March 2013, 11:05 AM
0.5mm is only for 5.8

Hugo

majkl
30th March 2013, 12:59 PM
Im guesing as long I make my blades tilting the same direction as on my tx clowerleaf I have the correct polarisation?

HugeOne
30th March 2013, 01:12 PM
Yep!

majkl
31st March 2013, 05:14 AM
thought I would share mine

http://s4.mojalbum.com/3579754_11472152_20639037/tehnikalije/20639037_z.jpg


http://s4.mojalbum.com/3579754_11472152_20639058/tehnikalije/20639058_z.jpg


http://s4.mojalbum.com/3579754_11472152_20639064/tehnikalije/20639064_z.jpg


http://s4.mojalbum.com/3579754_11472152_20639066/tehnikalije/20639066_z.jpg

Now just needs tuning and some clear lacquer and I can test it.

majkl
1st April 2013, 05:04 AM
Well back to the drawing board. I used the dimensions of the 1280, and hoped to adjust the center element to match my 1360 :D Doesnt work quite well.
What would be the dimensions for 1360?

A=4.291*(1280/1360) = 4.0385

Correct?

HugeOne
1st April 2013, 08:09 AM
Yes, correct.

-Hugo

Jasal
26th May 2013, 08:36 PM
Just about to start making a turbine for my receiver. Just wondering if RG402 wire would be ok? I think it's still 50ohm....otherwise I have some RG316 on it's way but it'll be a couple weeks and I'm itching to start building...

HugeOne
26th May 2013, 08:59 PM
RG402 will be fine.

Hugo

Jasal
27th May 2013, 12:56 AM
Is there a minimum length of the coax to avoid the fresnel zone? Or does that not matter for Rx's?

HugeOne
27th May 2013, 08:32 AM
I like at least 3/4 wave.

-Hugo

Jasal
1st June 2013, 01:16 PM
What happens if you go shorter? Is it just as important for Tx's?

HugeOne
1st June 2013, 04:56 PM
Your vtx/vrx enter the frenszel zone and performances/circularity is affected.

Cheese5
7th June 2013, 11:50 AM
Hugo, I'm trying to build a 5.8ghz turbine again for my video system. I've built many many skews and cloverleaves but they aren't doing that well (that curved part of lobes just doesn't work for me!) The channel I use is @ 5.945ghz, how will that affect the length of the wires (I will use 0.6mm wire)? Should I shorten them or lengthen them by x amount (I'm trying to make a antenna that resonates closest to my frequency)?

HugeOne
8th June 2013, 08:46 AM
Leave the dimension as is, the bigger wire you use will ship freq. upward close to the channel you using.

-Hugo

Cheese5
8th June 2013, 06:00 PM
Thanks Hugo, finished making one! 2~3hours of cutting, filing, soldering, and bending paid off!

Dave Parry
13th June 2013, 05:02 PM
Damm, just realised I built a turbine (8 arms) with the dimensions for the Virevent (4 arms). dohh.
Also couldnt get 5mm wire so used 6mm, but even so the size is out. Will have to take apart and start again. But not tonight. Luckily made a jig so a bit easier to build, but not a lot.http://fpvlab.com/forums/images/icons/icon9.png

skelator
4th July 2013, 09:48 AM
mandatory 5.8 to use 0.5 for turbine and 0.6 for fan? can't find those 2, i only have spool of 5kg 0.8 mig wired :)

HugeOne
4th July 2013, 09:57 AM
Using 0.8 wire will hurt axial ratio, which is the turbine/fan main advantage. Why go trough the pain of building a 5.8 turbine and end up with sub results?

-Hugo

skelator
5th July 2013, 01:55 AM
Using 0.8 wire will hurt axial ratio, which is the turbine/fan main advantage. Why go trough the pain of building a 5.8 turbine and end up with sub results?

-Hugo

why I just wanna experience different type of antenna and for the fun of building new stuff, I guess stick with cl/spw for 5.8 and turbine/fan for 1.3ghz :)

matzen
29th October 2013, 09:17 AM
Hey,

i justed finished my CL and SWP Antenna.
Now i discovered this thread.
How does the Virevent & Turbine antenna stand up against the CL (TX) and SWP (RX) using a 5,8 Ghz system?

HugeOne
29th October 2013, 09:47 AM
Assuming both are correctly built, the Turbine/virevent has the advantage of added circularity. It show on both paper and lab test, but out in the field with analog video link, things become highly subjective.
Many people say they see a difference for the better, which corroborate my own testing.

-Hugo

Adrianm1972
7th July 2014, 02:59 PM
Hugo, what would be the effect of building one of these so each lobe was one piece of wire and pulling the top wire down at the center to connect to the active element instead of using the wire extension?

HugeOne
7th July 2014, 03:32 PM
It'll change the center wire electrical length. Considerably raising resonnant freq.

Hugo

Adrianm1972
7th July 2014, 04:06 PM
It'll change the center wire electrical length. Considerably raising resonnant freq.

Hugo

I guess all the wire lengths would have to change then to bring it back....thanks I was just curious. I am going to build some 4 lobes for 2330Mhz in the next few days.

I really appreciate all the work you and Alex have done to move FPV along...thank you!

Zangetsu57
25th October 2014, 03:00 PM
Hey folks,

Had anyone used a bazooka balun with the Virevent or Fan antennas? I've been modeling and simulating a design derivative in CST and the feed wire length seems to affect the return loss and radiation patterns substantially as a function of length. I'm going to model a balun and see how well it performs.

Xerx
23rd December 2014, 03:53 PM
I hope these solder joints are acceptable, it wasnt exactly easy to get the center wire straight at 5.8 ghz.


56137
5613856139
5613556136

HugeOne
23rd December 2014, 03:55 PM
Look nice.

Hugo

IBCrazy
23rd December 2014, 11:05 PM
I hope these solder joints are acceptable, it wasnt exactly easy to get the center wire straight at 5.8 ghz.


56137
5613856139
5613556136

Are you a jewelery maker by chance? That's some really nice work!

Xerx
24th December 2014, 05:42 AM
No, just a regular university student.
A flux pen, http://upload.wikimedia.org/wikipedia/commons/thumb/3/3f/Rapporteur.svg/2000px-Rapporteur.svg.png, and a digital caliper helped though.

It did take nearly 3h to cut all the wires, file them to length and solder/bend it.

PS, a power tool is extremely handy if you want to bend mig wire straight. Mount it in one end then twist away while under tension. Once you twisted enough it will be close to completely straight.
Takes a few trys though, as if its not enough it turns out terrible, and to much and you stretch the wire.

Xerx
24th December 2014, 12:00 PM
HugeOne/IBCrazy have you tested encasing a 5.8 antenna(pingpong ball or similar), and then filling up the casing with polyurethane glue?
Its going to be a acceptable weight increase if it doesn't shift the frequency to much. The glue will be mostly air (assuming one doesn't overdo it with the polyurethane), but make the antenna as good as undestroyable on a 250 quad.

Xerx
24th December 2014, 03:45 PM
And done. I don't really recommend building the turbine using this guide, it ends up being quite fragile.
Iv already had to resolder one of the lobes (holy *censored* that was hard).
I dont expect the on on the tx to last long. However should be ok for the rx.


56226
5622356224

Adrianm1972
24th December 2014, 08:04 PM
There are instructions somewhere for building them with one piece lobes.

HugeOne
24th December 2014, 11:58 PM
It is here:
http://fpvlab.com/forums/showthread.php?3960-Windmill-fan-tutorial!
Although, there's no specific dimensions sets for the turbine, I'm sure you can figure it out.

Happy Christmas!!

Hugo

Funky Diver
13th January 2015, 06:58 PM
Is there any reason why the wire sizing on 5.8 needs to be smaller than 0.8 mm?

I have access to .65mm copper, how much would that affect the sizing on a turbine for example? If it's a size alteration, would that percentage hold true for a windmill, etc?

Getting back into the hobby and am back to square one apart from a couple of air frames and OSD's, so trying to make my cash go a long way else I'd just buy the antennas, lol. I do like the idea of a Sniper though.... in time, in time... still got my throws low for now, hah

HugeOne
14th January 2015, 12:30 AM
For 0.65 I say add and extra 1-1.5% to all measures. For good axial ratio I prefer small dia. wires.

-Hugo

Funky Diver
14th January 2015, 12:47 PM
Cool Hugo, many thanks. I'll go with 1.5% =)

TinyMuffin
17th January 2015, 05:32 PM
Hey, Hugo (or anyone else who has the answer),

Do you happen to know what the measurements would be for a 440 MHz turbine with 0.89 mm welding wire? Also, what would you do to alter those measurements to 433 MHz, if need be?

-TinyMuffin

HugeOne
18th January 2015, 08:48 AM
57229

Here, to move to 433, use can use a rule of thumb since it's close.

_Hugo

TinyMuffin
18th January 2015, 05:21 PM
Thank you very much! I appreciate it! So would the coax connect to the top of that or the bottom? And am I right in interpreting those measurements, in that the top wires are slightly shorter than the bottom?

Also, are you using a computer program for this? That picture looks like it was taken from some sort of design software.

In terms of general ability of the turbine, what does the signal strength do when the source is facing the top or bottom of the turbine vs the sides?

-TinyMuffin

HugeOne
18th January 2015, 11:04 PM
On the bottom, yes bottom are longer.
It is 4NEC2 software made by Aris Voors.

The turbine, like most omnis, have null on top and bottom.

-Hugo

dlearnt
31st July 2016, 10:05 PM
Hello Hugo,

I'm going to try making a 5.8ghz fan and a turbine, but would like to use your fan tutorial method (http://www.truerc.net/images/tutorials/Fan%20tutorial.pdf) rather than your Virevent/Turbine method (http://www.truerc.net/images/tutorials/Vireventtutor.pdf).

I noticed that at post #60 (http://fpvlab.com/forums/showthread.php?1497-Virevent-amp-Turbine-advanced-CP-antennas-tutorial&p=234594&viewfull=1#post234594) you gave dimensions for the 5.8ghz turbine using 0.5mm wire and the fan tutorial method (Arms, 1st bend, 2nd bend, centre, pitch).

I have tried to work out the dimensions for a 5.8ghz fan with 0.5mm wire using figures from your fan tutorial, but I'm not sure they are correct (link to a google spreadsheet (https://docs.google.com/spreadsheets/d/18r0hKkbAqUjAOSAhqtsVb9g4tdFJpS7-IcNVZBYwwfw/edit?usp=sharing)):

73774
My calculations proceed on the assumption that the dimensions of the 910 Turbine and 1180 Turbine are directionally proportional to the 5800 Turbine. However, I don't think that can be the case, because my 5800 fan dimensions taken from the 910 are different to my 5800 fan dimensions taken from the 1180.

dlearnt
1st August 2016, 04:33 AM
Ok, I just went back through the archives. I'm guessing that Hugo is not going to want to answer my question (rightly so, unfortunately for us DIY'ers):

From August 2012 (http://fpvlab.com/forums/showthread.php?3960-Windmill-fan-tutorial!&p=129382&viewfull=1#post129382):

"I really hate to say this, but sorry for the DIY builders but last thing I want to see is an IRC windmill/fan.

-Hugo"

HugeOne
2nd August 2016, 02:56 PM
My calculations proceed on the assumption that the dimensions of the 910 Turbine and 1180 Turbine are directionally proportional to the 5800 Turbine. However, I don't think that can be the case, because my 5800 fan dimensions taken from the 910 are different to my 5800 fan dimensions taken from the 1180.

The antenna does not scale that much unless you scale wire dia. too, which will make for a really thin wire at 5.8.

The fan/windmill design will be abandoned by us so I will release them to the community. Right now I'm in vacation, but will get to it when I'm back. Don't hesitate to knock at this thread if I forget. :)P

-Hugo

dlearnt
5th August 2016, 02:17 AM
The antenna does not scale that much unless you scale wire dia. too, which will make for a really thin wire at 5.8.

The fan/windmill design will be abandoned by us so I will release them to the community. Right now I'm in vacation, but will get to it when I'm back. Don't hesitate to knock at this thread if I forget. :)P

-Hugo

Whoohoo! That's fantastic news. Thanks Hugo.:D

HugeOne
1st November 2016, 02:03 PM
74897

5.8GHz fan dimensions
You may use 16.7+10.4+16.7=43.8mm wires and add little legs to solder along the coax.

-Hugo

gedo831
1st November 2016, 02:37 PM
74897

5.8GHz fan dimensions
You may use 16.7+10.4+16.7=43.8mm wires and add little legs to solder along the coax.

-Hugo
Wow! Thank you so much for sharing this valuable information to DIYer's community!
I will be making one tomorrow!