Build IBCrazy's 433MHz Turnstile antenna for FPV
ฝัง
- เผยแพร่เมื่อ 4 ต.ค. 2024
- this is my how-to on the Turnstile long range radio system for FPV. It is a dual polarized antenna with a spherical radiation pattern used to mitigate problems with vertical polarization.
Just finished building this and paired it with your turnstile on the rx side and was able to get about 1km with the plane on the ground and it still didn't glitch. Thank you man! This antenna is great.
Like a man in orthotics, I stand corrected. I missed the difference in dipole lengths. My apologies and doubting comments removed.
Thanks for the videos.
It is actually circular polarized, I know. However I call it dual polarized because the axial ratio is very low (~.52) and the polarization reverses across the Z-axis.
Model it in 4NEC-2 or any other modeling program. It's circular. Hence the different element lengths. The crossed dipoles come out to 53+J48 and 48-J44. That is circular!
The theory has been around,well along as the first radio, pick you up an old Ham antenna hand book, the most used is 468 divided by the frequency in mhz. Here's the deal, the same antenna may not work well for everyone's,depending on what types of applications and placement your using, may need some adjustment, SWR will burn up your radio's rf finals, the antenna needs to be on whatever your using it on when checked, there are easy way to this, SWR meters will save you money in the long run
Hello Alex very clear the antenna construction tutorial.
In what position should it be used in RC TX?
That is, in vertical position the wire with respect to the floor and the cross in horizontal position?
thanks for share
The turnstile actually does best horizontally polarized and thus your radio should be the same. This is perhaps the only time horizontal polarization is preferable for control or FPV.
Hi Alex Thanks for your ansswer.
This question comes because i still searching a sopution
My problem is, my 1.2ghz VTX (1.5W) is interfering with my RC 433mhz signal.
The video is clear and clean all the time, but I lose the RC signal just 100m away.
If I replace the 1.2ghz VTX with a 5.8ghz VTX (600mw)I can go to more than 2km with no RC signal problem (rssi 90%).
How can i solve this problem ??
@@fndfpv3678 - You are running way too much transmitter power. You are most likely overloading the front end of your receiver.
I like so much your tutorials, you can take a look to mines, maybe they´ll like you. The Lenth are in inch, aren't them? That antenna is used to Tx or Rx? or it could be use in both? I'm prety new on that and I'd like to learn as much as posible. Thank you!
What equations need to be taken into account in turnstile antenna dimensions?
Would a diamond antenna work better than a dipole if both were kept horizontal? In your long range fpv tutorial you used what appeared to be a diamond antenna. Are the diamond and dragon link antennas 5/8 wave? And why are they so long? A 1/4 wave is about 6.5" and the dragon is 16" I think. Where could a laymen learn more? I have built the dipole for orangelrs 1w and turnstile for my fpv wings. I het some beeping from my telemetry when I'm about 800 feet high and still in line of sight. That is why I'm wondering about different antennas. Thanks for all of your help.
Hello. First of all, thank you a lot for a great video. Could you please explain how to calculate antenna sizes for any frequency, not only 433 mhz? As I understand in your video 6.75" is exactly wavelength/4. But what is 5.85" ? Is it just 0.8666 of previous value or the formula is a bit more complicated?
It is more complicated and I am glad you asked this question. This is not easy to explain, but I will try:
One element (5.85") is shorter than 1/4 wave. This makes it capacitive (leading) by 45 degrees. The other element is longer than 1/4 wave (6.75") and thus it is inductive. It lags by 45 degrees. When phased 90 degrees apart, they actually create a circularly polarized wave. The elements are 100 ohms each and thus in parallel are 50 ohms.
Thanks a lot for the answer (I thought it's for compensating the Doppler effect :)! Is there any rule of formula how much longer or shorter than 1/4 wave the elements should be? Say, +10% and -10% would be OK or it's more complicated than that? Particularly I would like to make an antenna for 137 Mhz frequency, to receive images from NOAA 15/18/19 and Meteor-M2 weather satellites. Sorry if my question sounds stupid, I'm a software developer and don't know much about antennas.
And here is one more thing I don't quite understand. If the described antenna is for 433 MHz isn't the 1/4 wave about 6.81" - 6.82"? This means both elements are in fact shorter than 1/4 wave.
In a vacuum and as a superconductor, yes. However, the materials used as well as the environment slows down the signal propagation and thus the lengths are always shorter.
I'm making this antenna for my wing - but I am not sure if I should go with a second turnstile on my TX - or just use a dipole?
Will this help out for Dragon link? Im just asking? Looks nice.
what's the impedance of this antenna and wich coax are you using?
Hey crazy, can this be used on the 433mhz TX end? if not is there antenna I can make for the 433mhz TX? perhaps you could point me in the right direction. THANKS
Hello IBCrazy. What antenna combo you recommend for long range openlrs fpv wing 433mhz
Hi Alex,
Would this design work well for 868mhz as well? And if so would it be a simpel case of /2 for the dimensions?. Im in the process of making some custom dipoles for 868 as the TBS ones provided for the MicroRX have a slanted feed point (not 90deg) which i believe is reducing there effectiveness. Would appreciate your thoughts on this please.?
Of course it will work. Just scale it down ;)
Will this work with two ? My RX has two Antennas. Thanks
Hello alex antenna which I use in TX, it would look better with this antenna RX?
Wich measures I need for NOAA satellites?
what size wire?
Can ı use it as tx antenna for 433 mhz lora ?
You can, but I do not recommend using it for both TX and RX.
@@CAGreve1231 Thanks, if ı use UHF Semi-rigid Dipole 433 MHz antenna ı will have more range but no signal from z direction right ? I read something like to have spherical pattern in turnstile antennas the gain reduced. By the way, ı am planning to use 433 mhz biquad antenna for rx.
It's circular?? Well I've never seen a circular 433mhz tx antenna!! How strange.
Yes, technically it is circular. However I would advise not using it as one.
So what's the gain then?
2.2dbi
No sound?
This is not turnstile antenna. The turnstile antenna is the double dipole antenna
The irony of this comment...
Hello alex antenna which I use in TX, it would look better with this antenna RX?
I would use a dipole. Remember to have it in the same orientation as the turnstile.
Alex Greve ok, the dipole antenna is one with two horizontal rods? else I can install both horizontal and vertical? ratchet, I want to install on a bixler2 tail., apologize me so many questions, and thanks for the reply already