hi,

i fly fpv for a month now , started off with an easystar but i wanted something faster so i bought a funjet.

i fly with goggles (fatshark) and a 5.8ghz system with diversity receiver , i use the spironet antenna's and extra helical 5t which i point to the area i tend to fly most.

my goal is to fly low and behind obstacels like chasing around threes and stuff , i do not fly further then 500 meter (about 0.3mile) away .

can a antenna tracker in combination with a high gain antenna make for better video behind obstacles?

i also have a sony tvl 600 cam but when flying towards the sun evrything else get's dark , besides that i love this camera.

Originally Posted by krikkens

hi,

i fly fpv for a month now , started off with an easystar but i wanted something faster so i bought a funjet.

i fly with goggles (fatshark) and a 5.8ghz system with diversity receiver , i use the spironet antenna's and extra helical 5t which i point to the area i tend to fly most.

my goal is to fly low and behind obstacels like chasing around threes and stuff , i do not fly further then 500 meter (about 0.3mile) away .

can a antenna tracker in combination with a high gain antenna make for better video behind obstacles?

i also have a sony tvl 600 cam but when flying towards the sun evrything else get's dark , besides that i love this camera.

An antenna tracker+higher gain can definitely help, but 5.8 really isn't the best for penetration.

That said I use a Crosshair on my goggles, and a stacked fan on my quad (I wouldn't recommend that antenna for a plane), and can punch through 20 feet of trees at about 500 feet. I'm using the immersion 600Mw transmitter, which transmitter are you using? the foxtech 200mw? If so, the 400mw might also help.

A helical will perform pretty similar to a 7T helical, although my personal expereince puts it a little higher.

i'm also using the immersion 600mw tx

Well, You can always get a higher gain Crosshair. They can be made up to about 12DB, with a big reflector. Because it's more efficient that a helical, it should perform better. Hugo at Truerc canada can build one for you, or maineiack here on RCgroups can build you one aswell.

Originally Posted by gundamnitpete

Well, You can always get a higher gain Crosshair. They can be made up to about 12DB, with a big reflector. Because it's more efficient that a helical, it should perform better. Hugo at Truerc canada can build one for you, or maineiack here on RCgroups can build you one aswell.

but i will need a tracker no?

Originally Posted by krikkens

but i will need a tracker no?

Not really, the Beamwidth is still pretty wide. The 12DB crosshiar will still receive aswell as a Skew-planar wheel past 50 degrees off center in either direction. Personally, I would use your current helical and the crosshair, both point about 40-60 apart. This should give you a really good amount of gain over a large area.

Point the crosshair specifically where you want to fly

Originally Posted by gundamnitpete

Not really, the Beamwidth is still pretty wide. The 12DB crosshiar will still receive aswell as a Skew-planar wheel past 50 degrees off center in either direction. Personally, I would use your current helical and the crosshair, both point about 40-60 apart. This should give you a really good amount of gain over a large area.

Point the crosshair specifically where you want to fly

is this such an antenna?

http://www.hobbyking.com/hobbyking/s...rectional.html

Originally Posted by krikkens

is this such an antenna?

http://www.hobbyking.com/hobbyking/s...rectional.html

That is high gain, but it's not circularly polarized, so no I wouldn't use it.

Here is what I meant:

http://www.truerc.net/canada/index.p...7je25mk7rr3u62

If you email him, he might be able to make you an even higher gain crosshair.

http://www.readymaderc.com/store/ind...oducts_id=1088

This one is a high gain helical, personally I'd rather have the high gain crosshair.

You definitely need to stick with circular polarized on BOTH ends of the video link to get good performance. Oh, I know you can run one CP antenna and one linear and it will work, but for the best performance you need CP on both ends. That said, I would only buy CP antennas from Truerc or Readymaderc.

Originally Posted by philthyy

You definitely need to stick with circular polarized on BOTH ends of the video link to get good performance. Oh, I know you can run one CP antenna and one linear and it will work, but for the best performance you need CP on both ends. That said, I would only buy CP antennas from Truerc or Readymaderc.

hi thanks for the advice.

i will get me a tracker and then buy a high gain antenna .

no system works behing 100 feet of trees i guess?


thanks

-kristof-

Trees, unfortunately, block high frequency signals very well. I personally don't like trackers, I think they are more of a headache than they are worth, unless you fly without knowing where the plane is at in relation to you, you like going for MASSIVE distance runs (ie +30 miles) so you need/use an extremely narrow beamwidth antenna and so on. But, I believe, very very few FPV'ers do those kind of runs, and are usually capable of planning where they are going to fly and knowing where the plane is in relation to them (so as to not fly out of the beamwidth of the antenna).

AND, if you DO fly out of the beamwidth of the antenna, all you have to do is reach out with your hand and physically move the antenna.

For $62 (+$15 for lowpass filter) you can get fox-400 which is good to almost 2 miles with stock antennas. It operates at 1.3ghz band and will be able to penetrate objects much better than 5.8ghz. It will easily out-perform your controls if its 2.4ghz.

so the lower the frequency the better it penetrates?

i noticed there are 433mhz systems available for long distance , would it penetrate better too?

what frequency's use the guy's that fly very far ? 433 for video and what for control of the aircraft?

Record is on 433 control and 900mhz video.

A 1.28ghz TX/RX is definitely the best way to get more penetration.

Originally Posted by gundamnitpete

Record is on 433 control and 900mhz video.

A 1.28ghz TX/RX is definitely the best way to get more penetration.

hmmm, i don't think 900mhz will work over here(europe) as mobile phones are on this band..

thanks for the info..