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Old Dec 14, 2012, 11:50 AM
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The standard answer is "no" but in truth, yes it would work. The problem is that the antenna is infact circularly polarized. However the circularity reverses across the Z-axis. Thus, if you use it as a transmit antenna, you must only use dipoles on your receiver. Do not use a turnstile on both ends.

-Alex
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Old Dec 14, 2012, 04:22 PM
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I guess the best answer is "what is the best antenna for transmitting in your eyes?"
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Old Dec 15, 2012, 11:03 AM
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A simple dipole works great. This is what I use.

-Alex
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Old Dec 23, 2012, 08:53 PM
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Hi Alex, how are you man?

Is there any drawback if I mount the antenna like in the image?


As Im a glider pilot, using 90 degrees for the antenna legs will leave some parts outside the wings.

Changing the angles Ill be able to insert the whole antena inside the wing, but Im afraid if theres any losses doing that.

Will it work? thanks
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Old Dec 23, 2012, 09:49 PM
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There is some loss due to rotation of phase. If you do not let the angle exceed 120 degrees, you should be ok.

-Alex
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Old Dec 27, 2012, 08:05 AM
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Hi Alex,

I use the inner core of a SAT Cable 72Ω (pure Copper 1mm). I remove the shield and aluminum sheet cover and I keep the plastic cover of the copper wire (1mm) inside.
Is that ok or its wrong?

And if its ok, can I use the same diameter copper for 2.4 GHz also?

Can I use both for TX and RX (Telemetry Modules 433 MHz and 2.4 GHz)?

What is better for 2.4 GHz telemetry transceivers? Cloverleaf, Skew-Planar or Turnstile?

Too many questions but only you can answer


Constantinos
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Old Dec 27, 2012, 09:34 AM
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Just let it hang 18awg



Quote:
Originally Posted by FabioBrazil View Post
Hi Alex, how are you man?

Will it work? thanks
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Old Jan 01, 2013, 10:10 PM
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What if receiver has two inputs, like ChainLinkDare? Should i have two antennas like this?


Currently i fly with 2.4 RC, it is clear that antennas need to be 90 degrees form each other, but should any of those be vertical? or booth antennas need to be parallel to the ground, maintaining 90 degrees angle to each other?
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Old Jan 11, 2013, 12:01 AM
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Since my DIY UHF radios are nearly complete, I decided to go ahead and make me a turnstyle:


Now my question is does anyone see a problem with locating it here:


My primary concern is the wiring so close to the antenna, below the white strip is a line feeding 2 high power LED's which equal to about 700ma @ 5v and are PWM'd at about 2khz, also it puts the antenna at very close proximity to the aircraft fuse, which could cause potential blocking issues from one side of the aircraft, thoughts?
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Old Jan 11, 2013, 09:42 AM
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I did the same but ran mine out further on the wings even if the ends of the wires were past the actual wing.
I had 2 of these at first, but then went to one and a monopole for a while. I found my sander style antenna gave me the best result since i was using a diversity receiver.
I found the turnstile was good the higher you got, but not as good on lower level flying.
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Old Jan 24, 2013, 05:52 AM
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Subscribed.
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Old Feb 23, 2013, 04:29 PM
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Quote:
Originally Posted by IBCrazy View Post
Bad idea. The element thickness is critical. The lengths are actually quite loose but you must use 20-24AWG wire.

-Alex
Quote:
Originally Posted by i3dm View Post
Alex,

Will 18 AWG wire off a burnt computer PSU work well ?
Quote:
Originally Posted by IBCrazy View Post
It would do ok. It would be a little out of circularity, but you'll be ok for most purposes.

-Alex
Quote:
Originally Posted by IBCrazy View Post
Hmm, how to describe this?

The turnstile works by reactive phase shift vectoring. This is a fancy way of saying that the elements "fire" at different time intervals. Imagine the tips of the antenna going hot in a rotational sequence. Nice and circular. Now imagine two side by side pairs going hot together instead. The resultant vector is linear. Changing the thickness of the wire disturbs the firing sequence and makes it look more like the second case.

-Alex
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Originally Posted by Corocrumpler View Post
Hi Alex, again THANKS for sharing...

The video states 18-22AWG, your Quote is 20-24, which is correct? Because I was going to use wire that was right in the middle of the thickness range. You did state that element thickness is critical.. Or is the range really 18-24AWG?

Coro
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Originally Posted by m_beeson View Post
Alex,

What would the results be; If this antenna were built with

.035 mig wire?


-Mike
Quote:
Originally Posted by IBCrazy View Post
It would perform just a bit better, actually. Ideally you'd use .062" wire.

-Alex
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Originally Posted by m_beeson View Post
Thank you Alex,

I'll find some .062 wire, and build one.

I can't wait to see the results.

-Mike
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Originally Posted by Mike_Tosen View Post
Hi,

Sorry, maybe I am just missing something.
I am busy getting all the stuff to build one of these for my 433mhz system.
Also looking at using mig wire.
But now the spec and this is confusing me - originally it calls for 18-24 awg - which is 0.04 - 0.02 inch diameter or 1.02mm - 0.51mm diameter.

The 0.063 mig wire is 1.6mm diameter.

Am I reading this correct that 1.6mm diameter mig wire would work just fine ?
Or is it better to go for something thinner - like 0.8mm or 1mm wire ?

Thanks for the excellent writeup.
Mike
Quote:
Originally Posted by IBCrazy View Post
For 2.4GHz, the specs are on FPVLAB. I thin it's post #179 or so.

@Mike - You are over thinking this. The wire makes almost no difference at all. You can use 30AWG and it will work fine. I just had to put some kind of constraint on it, that's all.

-Alex
I'm really confused by some of your responses in this thread, regarding wire size, Alex. Could you clarify?

And is solid wire better than stranded?
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Old Feb 25, 2013, 11:02 AM
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No comments on post 102?
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Old Feb 25, 2013, 02:10 PM
Alex USA
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Alex, because I truly believe in your knowledge and gift - I have antennas at home only IBCrazy made

One simple question regarding turnstile - does it has any TOP or BOTTOM ?
If I want to put it on top of the wing (ZII to be clear) should I pay attention to anything or just keep the angle 90 degree and stick it ?

Is top of the wing any better/worse than bottom ?

Thank you

Alex
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Old Feb 25, 2013, 02:15 PM
Alex USA
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Originally Posted by billyd60 View Post
No comments on post 102?
Watch the movie again - anything between 18-22 AWG is the best ...

best regards
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