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Old Mar 19, 2011, 04:18 PM
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http://www.mwjournal.com/Journal/Com...tenna/AR_8587/
What do you think about this type of antenna?
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Old Mar 19, 2011, 05:28 PM
RC = FUN
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I just spent the last hour and a half attempting to build this and it's really making me mad. I still don't think it's right. Can someone tell me what I'm doing wrong?
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Old Mar 19, 2011, 05:32 PM
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Originally Posted by dimar View Post
http://www.mwjournal.com/Journal/Com...tenna/AR_8587/
What do you think about this type of antenna?
Interesting but the axial ratio is quite poor which means it would not perform well for multipath rejection.

OMM
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Old Mar 19, 2011, 10:22 PM
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Originally Posted by flyboy321 View Post
I just spent the last hour and a half attempting to build this and it's really making me mad. I still don't think it's right. Can someone tell me what I'm doing wrong?
That looks fine to me. It's LHCP from the pictures. What do you think is wrong with it?

-Alex
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Old Mar 20, 2011, 01:05 AM
RC = FUN
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I just felt like it wasn't aligned correctly or something.

I actually flew with that and the cloverleaf today.

When flying towards, away, and banking at distances I ha perfect video. But if I ever turned within 100-200 feet it would sometimes go to static, but not to the point of my linear (non cp?) antennas. I went out to 3/4 of a mile, and will start to push and test it once my DL arrives! -Tyler
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Old Mar 20, 2011, 03:18 PM
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And you were about ready to give up FPV due to frustrations

Those that aren't switching to circular polarization have no idea what they're missing.
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Old Mar 20, 2011, 03:53 PM
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+1 for Circular polarization. off topics, Alex any news about the antenna for the DL.

Anthony.
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Old Mar 20, 2011, 03:56 PM
RC = FUN
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Originally Posted by IBCrazy View Post
And you were about ready to give up FPV due to frustrations

Those that aren't switching to circular polarization have no idea what they're missing.
Not give up, I just wanted to go simpler. I'm still thinking about the fatsharks though

Alex, how do I test if it's a 1.0? Isn't their supposed to be a way if your impendence (I may have made that up, but it sounded right lol) is a 1.0?

Could I send it to you or could I check with a radio shack multimeter? -Tyler
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Old Mar 21, 2011, 07:38 AM
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Why send it back to me? I measured and prebent the wire for you. At the very worst the SWR is 1.2 which is still excellent.

Yes I am willing to test it for you, but why not just fly it? I am certain it will work well.

-Alex
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Old Mar 21, 2011, 07:39 AM
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Originally Posted by flight01 View Post
+1 for Circular polarization. off topics, Alex any news about the antenna for the DL.

Anthony.
Coming soon. I still need to work out a few bugs. This got pushed on the back burner while I finished the design of the CP BiQuad antenna.

-Alex
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Old Mar 21, 2011, 11:49 AM
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Thanks Alex,can't wait to try it.Will it be easy to built?.

Anthony.
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Old Mar 21, 2011, 04:42 PM
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I've exchanged some emails with Alex about this but thought it might be helpful in this wider discussion. Like many now, I'm switching to Cloverleaf (plane) and Skew Planar Wheel (ground). I'm currently trying to figure out the best way to integrate the SPW into my ground station. Last night I bought a styrofoam half ball from the local art store and sanded out the inside of it to make a dome for my fragile SPW. I've got a styrofoam wheel to close up the bottom and, though it's not pretty, I've got a nice dome to mount on the end of a pvc pole. HOWEVER...

While I understand this antenna should be mounted high, I now understand that I can't extend the coaxial from the antenna to the receiver without serious signal loss. So I believe that leaves me with mounting the receiver under the dome and extending the RCA and power connections from my receiver down the pole from my antenna/receiver to my ground station. So here's my question: what's the best way to extend those connections?

Years ago I remember trying to extend RCA lines to my stereo and I never was able to do it without creating a strong humming sound. Is there a good way to extend that RCA cable or some special connection?

How about the power cord? I remember reading somewhere that power cords out of your ESC shouldn't be extended. Does this apply to the receiver?

Thank in advance.
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Old Mar 21, 2011, 08:06 PM
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Originally Posted by Infernal Bill View Post
I've exchanged some emails with Alex about this but thought it might be helpful in this wider discussion. Like many now, I'm switching to Cloverleaf (plane) and Skew Planar Wheel (ground). I'm currently trying to figure out the best way to integrate the SPW into my ground station. Last night I bought a styrofoam half ball from the local art store and sanded out the inside of it to make a dome for my fragile SPW. I've got a styrofoam wheel to close up the bottom and, though it's not pretty, I've got a nice dome to mount on the end of a pvc pole. HOWEVER...

While I understand this antenna should be mounted high, I now understand that I can't extend the coaxial from the antenna to the receiver without serious signal loss. So I believe that leaves me with mounting the receiver under the dome and extending the RCA and power connections from my receiver down the pole from my antenna/receiver to my ground station. So here's my question: what's the best way to extend those connections?

Years ago I remember trying to extend RCA lines to my stereo and I never was able to do it without creating a strong humming sound. Is there a good way to extend that RCA cable or some special connection?

How about the power cord? I remember reading somewhere that power cords out of your ESC shouldn't be extended. Does this apply to the receiver?

Thank in advance.
Someone in another thread here in the forum used a network patch cable. This sounds like a good idea for this kind of application as they are shielded, and the connetors are of good quality too. It's also easy to get the propper matching receptables etc. and since they have eight wires, you should be pretty much all set with one cable going down from the mast to your ground station.

Well, at least thats what I intend to try out to solve the same problem.

Markus
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Old Mar 21, 2011, 09:28 PM
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Here are the antennas that I decided to make this weekend. I used 0.035" mig wire for the vee, the cloverleaf and the SPW. I just realized that the mig wire is flux core wire. I hope the flux core does not affect the performance of the antennas. I decided to make the antennas RHCP. Anyways thanks to Alex for the great tutorials. I will make a helical in the coming week hopefully.


Matt
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Last edited by matyou; Mar 21, 2011 at 09:37 PM.
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Old Mar 21, 2011, 11:01 PM
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Those look good, Matt. Flux core won't hurt the antenna at all. However I must warn you, once you fly the cloverleaf/SPW combination, that Vee/patch will forever remain in a box

-Alex
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