RC Model Reviews

I tried to make a decent comparison between a V antenna paired to a 9dbi Yagi and a Skew planar antenna paired to 6 turn Helical.
The linear was tested on a cloudy day with no wind and the CP was tested on a nice sunny day but it was windy and I was getting dealt to when I dropped down to tree level over the river. The most notable thing is flying up under the power lines (110kv)
I had the SPW on the wingtip of a 2 meter foam glider which was not ideal because of the drag but I wanted to see if it was worth a permanent change. i am going to make a new 6 turn Helical and see if I can get better performance.
In my opinion at 1010mhz the jury is still out on whether the extra drag is worth it.

http://www.youtube.com/watch?v=cvIWu-TKmGY

Let me know what you think guys and I was wondering if anyone else has compared linear to CP at lower video frequencies, I am almost certain 2.4ghz and above it is almost compulsory depending on where you fly.

Mark

Were you using a skewed planar (4-element) or cloveleaf (3 element) on the plane?

Unfortunately, as you've likely discovered, the CL antennas get pretty big and unwieldy at the lower frequencies so there is a trade-off.

As you've probably also noticed, the SP has a very low gain so with all else being equal, you'll likely get a little less absolute range, although the degradation in signal strength tends to be more progressive and predictable than with linearly polarized antennas.

I intend to run two FPV packs (one with linear polarization, the other with circular) on my HK EPP FPV model in a week or so and record both video signals. That should make it easy to get an absolute comparison - at least on 5.8GHz.

Yes it is a SPW 4 lobe, if I had of thought I would have used the Yagi on diversity to check against the helical because my helical is pretty rough 3dbi down for the yagi going linear to CP would have been interesting. The linear setup I used has been 10km at 12 meter altitude, will try the CP setup soon in this noise free area. Look forward to your 5.8ghz test on the HK EPP model. I don't know if you have seen this thread about you and your backpack circuit on FPVLab.
http://fpvlab.com/forums/showthread.php ... -esc-noise

Mark