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Old Mar 07, 2011, 08:43 PM
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Yes, that's LHCP. You need to bend the elements 90 degrees and you'll have RHCP.

-Alex
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Old Mar 07, 2011, 09:20 PM
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Going to test mine out tomorrow, going CP on both antennas and cant wait!

Will let you guys know how it goes. I will be using a Skew Planar / Cloverleaf.
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Old Mar 07, 2011, 11:34 PM
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You will be amazed at your video quality improvement. I certainly was
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Old Mar 08, 2011, 02:31 AM
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The way I remember which polarisation an antenna will be is by looking at single element from the outside.
It depends on which way the element 'leans' from the bottom point to the top point.

So, an element that looks like this \ is leaning to the left = Left Hand CP

and an element that looks like this / is leaning to the right = Right Hand CP

Nigel.
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Old Mar 08, 2011, 04:17 AM
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Last edited by Mictronics; Jul 02, 2012 at 01:25 AM. Reason: Tired of RCG - Quality can be found at FVLAB
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Old Mar 08, 2011, 06:20 AM
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Soldering of connections

I am hoping to build this antenna for 2.4GHZ but am having slight problem understanding the way that it is connected to the coax feed. I can see that the two arms of the antenna are soldered at right angles at the mid point of the long sides. Is that where the screen of the coax is soldered? That leaves the four ends of the arms. Do they get soldered together with the inner of the coax?

Peter
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Old Mar 08, 2011, 06:21 AM
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Peter - Yes, that is correct. The 4 ends get soldered to the coaxial cable cienter element, the shield gets soldered to the cross junction.

-Alex
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Old Mar 08, 2011, 11:01 AM
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Thanks Alex,

Which do you recommend the pin wheel or three leaf clover?

Peter
Quote:
Originally Posted by IBCrazy View Post
Peter - Yes, that is correct. The 4 ends get soldered to the coaxial cable cienter element, the shield gets soldered to the cross junction.

-Alex
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Old Mar 08, 2011, 11:11 AM
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For the TX I recommend the cloverleaf. For RX I recommend the skew-planar wheel.
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Old Mar 08, 2011, 11:41 AM
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Oops had mine backwards lol, had my Clover on the RX and vice versa. I will switch it out before I fly!
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Old Mar 13, 2011, 08:58 PM
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Quote:
Originally Posted by Devonboy View Post
The way I remember which polarisation an antenna will be is by looking at single element from the outside.
It depends on which way the element 'leans' from the bottom point to the top point.

So, an element that looks like this \ is leaning to the left = Left Hand CP

and an element that looks like this / is leaning to the right = Right Hand CP

Nigel.
Now that's an explanation I can understand. I could never quite figure out L/H, R/H polarization until now. Thanks.
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Old Mar 14, 2011, 12:14 PM
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Hi, I'm going to build a spw antenna for my 2.4Ghz vrx and a cl for the vtx.

I have a question regarding the intersection angle of the spw.

Quote:
Originally Posted by Ibcrazy
The tip of the wire should meet the center at a ~105 degree angle. It will not (and should not) intersect at 90 degrees.
After using this online calculator:

http://www.handymath.com/cgi-bin/arc18.cgi?submit=Entry

I find the angle should be more like 114 degrees.

What angle is correct?
Am i overthinking this?

Cheers
crezz
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Old Mar 14, 2011, 01:10 PM
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You are overthinking it The point of that statement was just to keep people from trying to force a 90 degree intersection.

-Alex
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Old Mar 14, 2011, 03:42 PM
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Hi everyone,

IBcrazy,you are a genius.I have built and try your CL antenna on 2.5 ghz and I must say that I have never been able to get such a clear video in all directions of flying since i have started FPV 2 years ago.I have try all sorts of omnis,patch,etc(except yagi) and I have always had noise.I have used the CL antenna on both the TX and RX and up to now I have push it to 1 km with crytal clear video( need some tweaking on my Dragon Link set up before pushing further).I will post a picture of the antenna and a video asap.Thanks again for sharing your ideas with us,Continue the good job.

God Bless,
Anthony.
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Old Mar 14, 2011, 11:12 PM
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I'm glad to hear that

It's stories like that which push me to develop even more stuff and post it here. Helping people be successful in FPV is why I post on this forum.

Have fun!

-Alex
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