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Old Jun 13, 2012, 06:53 PM
Because gas is for BBQ's
nogas's Avatar
Australia, QLD, Brisbane
Joined Feb 2011
729 Posts
Help!
How will i know when i'm getting close to my video systems range?

I'm a relative newb to FPV and really enjoying the buzz of pushing out a bit further each time i go out.

I am experiencing some static / snowing every now and again and i occasionally get full screen static that lasts for maybe a second at most (i think this is mainly due to antenna placement which i'm working on) but generally the picture is very clear.

My main concern is i have no idea on what to expect when i am getting close to my video systems range. I have no idea if it will just drop out or if i will have fair warning. Will the image get grainy and slowly deteriorate or will i just get more regular static which suddenly drops out completely?

Any footage clips or explanations of what is typical would be appreciated.

If it helps i'm running 5.8Ghz, 600mw immersionrc vtx, 5800duo, with a SPW on one rx and 'will' be running a 5 turn helical on the other rx when i start pushing out further.
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Old Jun 13, 2012, 07:36 PM
BEOWULF
North vancouver, B.C. Canada
Joined Apr 2008
18,070 Posts
When you circle around and gain alt.

Move your antenna for video rx

Fly into the wind so you can find video range but still feel comfortable if video lost as wind will bring you back into video range

Loss of complete video is video range, reason to fly higher and do circles
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Old Jun 13, 2012, 07:49 PM
Because gas is for BBQ's
nogas's Avatar
Australia, QLD, Brisbane
Joined Feb 2011
729 Posts
Thanks David, that sounds like good advise for when i want to test my range but i'm more looking for details on how my video will look when its getting close to range.

Obviously when i lose visual then i am 'out of range' but i'd rather know the warning signs before it gets to that.

At the moment, every time i get a solid static screen (only about 1 - 1.5 seconds max so far) i cant help but think that i am about to loose video but my picture is crystal clear as soon as it comes back, so i doubt its getting close to range but i have no real idea???
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Old Jun 13, 2012, 07:58 PM
BEOWULF
North vancouver, B.C. Canada
Joined Apr 2008
18,070 Posts
Nice :rolleyes

But depending on you set up for video your actual experience will differ


Try to walk away with your ground station and experience video loss for your self as all classes will be different ,

Get a rc car and putthesystem on it and then do video experiments

Seeing others loose video is not the same experience as you might find with your set up

Good luck and have fun
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Old Jun 13, 2012, 08:37 PM
Registered User
United States, TX
Joined Oct 2010
331 Posts
Your range will depend on how much static you can stomach. For my 900mHz systems I can tollerate a bunch of static because I know from experience it will not all of a sudden drop out. my 2.4ghz systems are a different bird. interference can cause sudden drop outs (its done it to me before) and these effects are worsened when signal strength is not at its best. For my 2.4gHz systems Ill usually turn around when I start getting a little static. which is a couple miles for me depending on where I fly. Around my house I get lucky to make it a mile on 2.4ghz, out in the country on my ranch I can go 5 miles on the same system.

My advice would be to just experiment, start with turning back at the slightest bit of static and keep pushing the boundry to where you feel comfortable.
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Old Jun 13, 2012, 08:39 PM
Because gas is for BBQ's
nogas's Avatar
Australia, QLD, Brisbane
Joined Feb 2011
729 Posts
Sorry david, no offence intended with the rolleyes .

I do have an RC car but i doubt the RC link on that will get me as far as my video and i would need a massive flat paddock to reach my AV range while still maintaining control of the car.

At the moment i'm getting out to about 1.2 - 1.5 kms with good clear image with the occasional static mentioned.

I'd love to be able to test it on the ground but without any clear flat ground within hours i dont think its possible. I guess i could position the vtx / camera on top of a hill and drive a few kms away and check it from different distances but again the image is likely to be affected by freznel zone and multipathing issues at the vtx end that aren't usually apparent when the plane is in the air. Giving a different result to what i would see in real FPV use.

I guess my main question is, is it common to get gradual degradation of video (in which case i can keep pushing) or is it common to have a sudden drop out? Assuming clear LOS.
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Last edited by nogas; Jun 13, 2012 at 08:44 PM.
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Old Jun 13, 2012, 08:43 PM
Because gas is for BBQ's
nogas's Avatar
Australia, QLD, Brisbane
Joined Feb 2011
729 Posts
Quote:
Originally Posted by Slaphappysamy View Post
Your range will depend on how much static you can stomach. For my 900mHz systems I can tollerate a bunch of static because I know from experience it will not all of a sudden drop out. my 2.4ghz systems are a different bird. interference can cause sudden drop outs (its done it to me before) and these effects are worsened when signal strength is not at its best. For my 2.4gHz systems Ill usually turn around when I start getting a little static. which is a couple miles for me depending on where I fly. Around my house I get lucky to make it a mile on 2.4ghz, out in the country on my ranch I can go 5 miles on the same system.

My advice would be to just experiment, start with turning back at the slightest bit of static and keep pushing the boundry to where you feel comfortable.
Thanks samy. Sounds like its going to be a case of trial and error. Hopefully more trial than error.
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Old Jun 13, 2012, 09:00 PM
BEOWULF
North vancouver, B.C. Canada
Joined Apr 2008
18,070 Posts
You are a cool guy

Flying up high and into the wind will be good choice

When you come back home you can fly lower as you come back

Still turn around and get feel for video as slight angles make world of difference ie good idea to manually aim video rx antenna

Also further away than closer gives better video, as it all depends on set up

Wind and height will be your friend

Try ground range tests with video as well as rc
Do both tests with each on and of respectively

Test for video and rc control on ground

Be careful of low volts with video

Regulators also can make video go in and out poorly with rapid voltage change, or low volts
So when poor video turn down or off motor till closer to home

Sometimes going out is better video but practice with better video in than out
Ie tilt omni slightly 2 degrees forward as example on plane,,

This also is a test for video on the ground

Practice on simulators for google earth with flight sim and slowest plane flaps down

Close your eyes and reopen them tp practice orienteering with no video

Motor on and elevator up, rudder left, is good video fail safe setting, as it will regain video as an example

Flying with no video is a rush
Not a better feeling than regaining video while always having rc control
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Old Jun 13, 2012, 09:48 PM
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Joined Sep 2007
703 Posts
Quote:
Originally Posted by nogas View Post
Thanks samy. Sounds like its going to be a case of trial and error. Hopefully more trial than error.
nogas I am in same boat as you. The little drops for at most 1-2 seconds I have now experienced enough to know that is not how video range is indicated. In my system, and as others point out it is different based on the system, I think there is a form of static development for max range indication.

Here is why:

I have 3 antennas. all 1280 mhz. cloverleaf, biquad, helical. hooked to 2 eagle eyes. cloverleaf is primary, I rarely get a diversity change within 5000 feet. out over 5000 feet, it quickly changes to the biquad. there is static that develops before the switch, but the biquad takes over too fast so I can't see the static limits. Then as I get further out... I start to see a consistent pattern develop. Not a sudden 1 second burst which happens now and then. but a faint static consistent pattern then my helical takes over at 15,000 feet out (LOS, legal altitude over forest I love where I live). I have not gone far enough to see static on the helical.
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Old Jun 13, 2012, 10:49 PM
Just trying to get a nut.
scrtsqrl's Avatar
United States, VA, McLean
Joined Oct 2006
6,118 Posts
Quote:
Originally Posted by nogas View Post
I'm a relative newb to FPV and really enjoying the buzz of pushing out a bit further each time i go out.

I am experiencing some static / snowing every now and again and i occasionally get full screen static that lasts for maybe a second at most (i think this is mainly due to antenna placement which i'm working on) but generally the picture is very clear.

My main concern is i have no idea on what to expect when i am getting close to my video systems range. I have no idea if it will just drop out or if i will have fair warning. Will the image get grainy and slowly deteriorate or will i just get more regular static which suddenly drops out completely?

Any footage clips or explanations of what is typical would be appreciated.

If it helps i'm running 5.8Ghz, 600mw immersionrc vtx, 5800duo, with a SPW on one rx and 'will' be running a 5 turn helical on the other rx when i start pushing out further.
4 miles (2 min 12 sec)
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Old Jun 13, 2012, 11:11 PM
Registered User
Australia, VIC, Melbourne
Joined Sep 2001
493 Posts
Hey, a good demonstration & some good pointers there scrtsqrl.

Nogas, you could place a RF attenuator on your VTX that would simulate long range at a much shorter distance, as you walk away you would see gradual degradation of your signal. I know this wouldn't actually test your range but it would demonstrate what you would see. Just an idea.

Regards,
John
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Old Jun 14, 2012, 05:42 AM
Registered User
Denmark, Region Zealand, Greve Strand
Joined Oct 2008
83 Posts
Hi Nogas
I to am new to FPV (had my first FPV flight yesterday )
I have been using the last 4-5 months to learn about this FPV stuff and i still feel like a newbie
But i belive your main question was how the picture degrades in flight
That is a tuff one - but if you look at " Yet Another Newbie 5.8GHz Setup - A Catalog of Statics " here on RCG you will find a series of pictures of different situations where the picture degrades

Hope this helps

Jan
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Old Jul 26, 2012, 02:59 PM
SpliceMILK, BeverlyHills,CA
LexusFPV's Avatar
Joined Feb 2011
1,200 Posts
Dont use 5.8ghz for Video if you want to fly out far....

use 1.2ghz Video and use Long Range CP antennas',
You'll go further out, more range then the Bixler/SkySurfer will ever go:-)
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Old Jul 26, 2012, 04:55 PM
Registered FPVer :)
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Switzerland, LU, Buchrain
Joined Aug 2006
2,717 Posts
Quote:
Originally Posted by LexusFPV View Post
Dont use 5.8ghz for Video if you want to fly out far....

use 1.2ghz Video and use Long Range CP antennas',
You'll go further out, more range then the Bixler/SkySurfer will ever go:-)
Define far. If far is 15km, then use 5.8Ghz video. I can tell from personal experiance that video does not drop out immediately except if you fly behind a solid object. If you do so, this will happen on all frequencies if you are somewhat out. It's true that 5.8Ghz due to the frequency will not reach out as far as the lower bands, but I bet most FPVers never fly out more than 10km ever.

The video degrades pretty slowly, ESPECIALLY on 5.8Ghz. Even if you get complete snow and continue flying, the signal in almost all cases (well, in all I stressed this) returns. Not to say that you should force it that bad, but it will not cut out immediately.

Depending on where you live, be aware that 1.2Ghz as well as 900Mhz can be illegal, not so with 2.4 or 5.8Ghz.

Markus
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Old Jul 26, 2012, 06:29 PM
Because gas is for BBQ's
nogas's Avatar
Australia, QLD, Brisbane
Joined Feb 2011
729 Posts
Thanks everyone, after many flights over the last month or so i have had the oppurtunity to test my set ups capabilities. Some 'testing' was encouraging, other 'testing' didn't end so well.

But all in all, what Markus said is bang on what i have found. The video quality generally fades out gradually, unless LOS is interrupted (realised by unintentional 'signal penetration testing' that didn't end so well)

What i have found so far is that everything seems to be trade off. When improving one aspect of my system i tend to lose in another area. But i guess that is one of the fundamentals of life.

At the moment i have only pushed out to about 1.5 kms and the video has generally been good but at that range i was getting some noise / graininess that i think had to do with my wiring and component layout. I have recently changed the layout to improve component and wiring seperation but now my plane flies like a pig.

I am hoping to get a chance to do some ground level range testing of all components this weekend to try to isolate the problem areas.

Fun and games..........
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