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Old May 25, 2011, 03:06 AM
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Romania, IS, Iasi
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Here is a video test made in hard weather conditions : very very windy.

5,8 ghz test 1 (3 min 48 sec)


Sistem is 5,8ghz 200 MW.

I've used on the video tx Cloverleaf antenna (3lobes) and on the video rx a Skew Planar Wheel (4lobes).

The tx is placed on the tail of my twinstar , rx at 1,5m height from the ground.

CH 4 used.

Questions:

If i will place higher the rx the signal could be better?

the 1000m distance is the limit ?

Thanks,

P.S. Sorry if i am offtopic.
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Old May 25, 2011, 03:26 AM
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I was really hoping to get 2-3 km with CL and SPW...

- Jeff
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Old May 25, 2011, 04:09 AM
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Switzerland, LU, Buchrain
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Originally Posted by Vitamin_J View Post
Thanks for the help guys, I think my problems are gone. IBCrazy, on both sma connectors the pins were too short. I pulled them out and today I just flew a full 1km! I probably could have gone further but I'm still using Spektrum and I don't want to push my luck too much.

Here's the vid:

http://www.youtube.com/watch?v=abE82yGiXS8

I have some bad interference in the middle/end from about 500m out to 200m out and at pretty high altitude, I think it may be components in my plane blocking the signal and when I get closer a dead zone in the coverage. Does this sound right? I was also flying near a power relay station or whatever they're called as well as some high tension wires.
Interference in fact is bad. Should not be that bad at this range. Might be components blockinig the path. I usually put the CL below the fuselage and if it's not possible as high on the rudder as I can. Yours is no the tail boom if I remember correctly and this means that you will have problems if you fly towards you. Do you remember if the disturbed signal phases were when flying towards you?

Markus

[Edit] Pulling those pins out also is critical. The connectors are delicate. In fact according to their specs you would have to tighten them with a given torsional moment. Also NEVER turn the complete connector but always only the nut. Otherwise you wear out the pins coating. Again, this is HF stuff, and there are things to watch out for. [/Edit]
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Old May 25, 2011, 04:15 AM
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Originally Posted by jkarnacki View Post
I was really hoping to get 2-3 km with CL and SPW...

- Jeff
Jeff,

If your setup is good, read using the proper tx&rx with GOOD CL and SPW antennas, there is no reason why you should not got out 2-3 km with this setup. My and my flybuddies do this on a regular basis.

The problem IMHO is that one has to be aware of the implications dealing with such high frequencies. This starts with the material choosen to make such an antenna, how its soldered, if the lenghts and the shape are optimal and of course anything else in the complete signal path. If it's done correctly, it works VERY well.

Markus
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Old May 25, 2011, 04:21 AM
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Quote:
Originally Posted by kempo View Post
Questions:

If i will place higher the rx the signal could be better?

the 1000m distance is the limit ?

Thanks,

P.S. Sorry if i am offtopic.

Placing the Rx antenna higher is a good idea. Mine is about 3 meters off the ground. No, 1000m is not the limit. what you observe there is typical. It takes some balls to just fly a bit further as it seems (at least on 5.8Ghz) there are like "areas" where the signal is a bit bad, soon going back to what it was before. Fix your rx antenna placement first, then retry. Maybe you place a spotter out there which could give you instructions what to do should you really loose the signal permanently.

No, you are not off topic. This thread is about flying far out with 5.8Ghz. Totally on topic IMHO.

Markus
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Old May 25, 2011, 04:33 AM
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Originally Posted by IBCrazy View Post
My sets are actually tuned to 5775MHz. The closer you atre to that channel, the better the antennas work.

Hiya,

Interesting ! can I buy a tuned up one??? I have an airwave 25mw TX to go on the plane
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Old May 25, 2011, 10:29 AM
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Amherst, VA
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I never considered making channel tuned units, but the band is so wide I might do that in the future. For now, I only have the 5775MHz units available as that is the middle of the legal 5.8GHz band.

-Alex
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Old May 25, 2011, 11:24 AM
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Germany
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Originally Posted by IBCrazy View Post
I never considered making channel tuned units, but the band is so wide I might do that in the future. For now, I only have the 5775MHz units available as that is the middle of the legal 5.8GHz band.

-Alex
What is the best way you go about tuning your antennas? If I can get another 10 meters I will do anything for it. Sad but true
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Old May 25, 2011, 11:34 AM
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Originally Posted by whakahere View Post
nice one, pity I can't see the video. Germany and youtube they block everything if it has music I can't see the video so I can't really tell what interference you are getting. How high were you?

Going out 1 km on spectrum! be bloody careful. Spectrum has a problem of giving out really easy in range.
Try watching now, I changed up the track. Yeah, I've read all about Spektrum and FPV.
Quote:
Originally Posted by markus123456 View Post
Interference in fact is bad. Should not be that bad at this range. Might be components blockinig the path. I usually put the CL below the fuselage and if it's not possible as high on the rudder as I can. Yours is no the tail boom if I remember correctly and this means that you will have problems if you fly towards you. Do you remember if the disturbed signal phases were when flying towards you?

Markus
Yes, it was worse when flying towards myself. There is a carbon spar in the boom, I could put the CL upside down under the spar, but it'd be right next to it. Would I be better off putting the CL on top of the tail?
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Last edited by Vitamin_J; May 25, 2011 at 11:49 AM.
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Old May 25, 2011, 11:43 AM
Kiwi in Germany
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Germany
Joined Jun 2010
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Quote:
Originally Posted by kempo View Post
Here is a video test made in hard weather conditions : very very windy.

http://vimeo.com/24176205

Sistem is 5,8ghz 200 MW.

I've used on the video tx Cloverleaf antenna (3lobes) and on the video rx a Skew Planar Wheel (4lobes).

The tx is placed on the tail of my twinstar , rx at 1,5m height from the ground.

CH 4 used.

Questions:

If i will place higher the rx the signal could be better?

the 1000m distance is the limit ?

Thanks,

P.S. Sorry if i am offtopic.
not off topic like markus said by the way. This is all about the range we can get on 5.8ghz and to stop that silly talk that you can't go far on 5.8ghz

All I need to do is go further than 6km to beat a swiss guy I know


To me you seem to be going a little out of range and the reason is your site. You are flying over a town at that time right? I have noticed that you can go longer distances when not over towns at range. With the wifi bands at a longer range I seem to hit a wall when flying over a town. 500meters to the side of the town and all is fine. Back to the distance again. I can EASILY fly 1km over a town with next to no interference. those drop outs are loss of signal so either put you antenna on your tail or better yet under your plane upside down. FYI the signal will go through foam.
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Old May 25, 2011, 11:52 AM
Kiwi in Germany
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Germany
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Quote:
Originally Posted by Vitamin_J View Post
Try watching now, I changed up the track. Yeah, I've read all about Spektrum and FPV.

Yes, it was worse when flying towards myself. There is a carbon spar in the boom, would I be better off putting the CL on top of the tail?
yup I can see it. You are having multipathing issues. See those drop outs where you have black? that is multipathing not lack of range. At the start of your video you have waves of static and that is loss of signal due to range/interference from the wifi below you (houses) and range. You are right about your dead zones. That is when your signals are being blocked by things such as batteries/carbon fibre.

I have my antenna on my tail, well away from everything. I do still get some interference at long range but very little multipathing unless at around 5km when the signal is weaker and narrower. So either place you vtx well away from your components like batteries, carbon fibre, camera. The BEST place is under your plane but if you are like me you and you belly land the best place I have found is the tail tip. Nice and high.
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Old May 25, 2011, 01:25 PM
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Quote:
Originally Posted by Vitamin_J View Post
Try watching now, I changed up the track. Yeah, I've read all about Spektrum and FPV.

Yes, it was worse when flying towards myself. There is a carbon spar in the boom, I could put the CL upside down under the spar, but it'd be right next to it. Would I be better off putting the CL on top of the tail?
You mean embedd it in the tail? If you can do this so as the spar is above the hanging cl I'd say you are ok.

Markus
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Old May 25, 2011, 02:21 PM
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Awesome, thank you for your help! I'm happy with the performance for now, but when I decide to go for longer ranges I'll embed it all the way out at the back and bottom of the boom, maybe I can replace some of the carbon with wood as well.
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Old May 26, 2011, 04:54 PM
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Germany
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Originally Posted by Vitamin_J View Post
Awesome, thank you for your help! I'm happy with the performance for now, but when I decide to go for longer ranges I'll embed it all the way out at the back and bottom of the boom, maybe I can replace some of the carbon with wood as well.
I have carbon boom and surrounding my vtx (not antenna) in my tail to give it a little extra strength in my twinstar. It is all about placement. Carbon fibre sucks up the signal so get things far way from it. Pretty much if you have your antenna needing to point much of it's signal through carbon then it is time to move it away to another point. The distance I have it away I don't get much of a difference when the plane is facing towards the receiver so the carbon here isn't sucking up much of the signal.

@markus here are the photos. I keep meaning to send them to you so I thought it would be easier just to post them so you don't delete the mail again Close up of the hecker transformer. It should be a little smaller overall in the height. It is about 1mm to big.
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Old May 26, 2011, 05:01 PM
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Romania, IS, Iasi
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whakahere,

Nice twinstar what setup do you have on it ?

Yout pan-tilt sistem is this one : http://www.bevrc.com/bev-platic-pantilt-p-212.html ?

i have one too but i didn''t find the proper servos to use.

What servo do you have ? 180 degrees pan ?

Edit:

tomorrow i will try again to see if i can break the 1500m barrier .
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