Would love to get some pointers on my first fpv setup.

[OzFlyer]

Hi,

I am brand new at fpv and I have constructed my first fpv setup. I am having some problems. They are as follows:

1. I have a dx61 and I read from another thread that it is possible to get at least a 1km (3500 foot) range. My failsafe kicks in sometimes at not even 300m los.

2. When I plug in battery the ailerons, rudder and elevator twitch. This only happens when I go through rvosd.

3. When I land the video signal breaks up and I can't see my peaks in altitude etc.

equipment used:

rc tx: dx6i with 6200 rx
video tx: range video 900
osd: rvosd
plane: Twinstar 2

I have got my rc rx in the front under my video tx. I know this may be bad, but i thought since one is 900mhz and other is 2.4 ghtz it would be ok.

The current sensor is here also next to battery and rc rx.

I cut a hatch in back rear of plane and inserted osd.

I put my gps outside plane behind wings which btw works great.

 

[Alex Villa]

You do have very bad positions for both the R/C Rx and antenna satelite. the small gray wire comming out are the antennas. and the better gain for both are to the wider sides. In your case the satellite has the signal obstructed/interfered by the battery, and the main receiver antenna to close to the surrounded wires.

 

[CaptnKliegle]

Get the RC RXR antennas away from any metal (i.e. aluminum foil covered Lipos). Can you place it far forward of the battery?

I use AR6200's in numerous aircraft, and always have the antennas pointing straight out from the plastic housing, and also have them installed 90 degrees relative to each other. i.e. one set of antennas are mounted vertically (vertical polarization) and the other reciever mounted horizontally (horizontally polarized). Think of how a diversity RXR antennas are mounted when used for the 900Mhz video down link, the AR6200 is essentially a diversity RXR.

This mounting technique keeps one of the RXR's antennas relatively broadside to the TX antenna (which should be positioned perpendicular to the plane as well if using the stock 2dB gain monopole antenna or similar) which improves RXR's performance. (Remember how they advise NEVER point the antenna at the aircraft.... because most of the RF energy is radiated perpendicular to the antenna.

Flying high directly overhead, the horizontally mounted antenna in theory will have a better signal than the vertically mounted one (providing the TX antenna is horizontal) The opposite is true when flying out low on the horizon, where the vertically mounted antenna will have a better signal (providing the antenna is vertical).

When flying visually (non FPV) my antenna on the DX6i is angled at about 45 degrees. I physically hold the transmitter so the antenna is ALWAYS perpendicular to the aircraft and range is never an issue (other than visual range).

Also, get the 900Mhz TX antenna far away from the 2.4Ghz RC RXR. It's called front end overload... same thing when you drive by a FM radio station and it bleeds over onto the station you were currently listening to... until you get some separation...ie distance. Yes, 900Mhz and 2.4Ghz are long ways apart frequency wise, but placing a 500mW transmitter antenna near a sensitive 2.4Ghz receive antenna will reduce range!

Kriss KA1GJU

 

[OzFlyer]

Hey thanks,

Thanks Kris and Alex,

What you say makes sense to me. And it concerned me before, but wanted that extra push from someone who knows.

I have added more pictures to show that I have taken your advice.

I saw that in the nose there is unused room. (As you said Kris). So I decided to try get my main rc rx away from everything.

I found the nose is solid foam so I cut a slot into it and simply placed rc into that. Can,t get much further forward than that. This way it is away from vid tx, battery and the carbon rods that I used for extra support. The antenna poke out the sides and look like the plane has whiskers.

The remote antenna is vertical and is placed a bit further in. I may have to play with this because I may have to move battery so it is not getting interferance from it.

The wires like Alex said may still be close to it, but I will test this and maybe twist or plat all servo leads.

Here is some photos. By the way please ignore my sticky tape camera holder. My SPC cam pan and tilt is on its way.

Thanks again.

 

[OzFlyer]

Did one more thing

I also simply twisted the video tx around so it is a further 5cm away from rx.
Should be interesting to see how this goes.

I also tidied up my tape job. This transparent material tape is awesome.

 

[Alex Villa]

The receiver antenna setup on the front of the plane is good. The satelite position is still bad.

 

[OzFlyer]

Hows this??

Hi Alex,

I decided to put the antenna satellite up front as well. Lets see what you think. Here is photo.

Also one more thing. I notice my servos still twitch.
I have just ordered some ferrite rings and am planning on platting wires (well wife will)

Do you think this will help?

 

[Alex Villa]

I like it much more now.

 

[OzFlyer]

Hey Alex, Cheers for the pointers. Much appreciated. I did not get a failsafe today . I can now feel comfortable fpv flying around my park without my knees shaking to much. I think it is time to engage the rth before I go out much further.

Mrleenagle

Thankyou very much for that very nice offer. I don't know anybody else who does fpv and would love you to look at my plane.

However I am actually in Brisbane Then I got thinking and realised we are doing a roadtrip in a month because we move to Adelaide. And we would like to pass through Sydney, Melbourne etc. So if you are available then that would be great. It would give me time to sort my stuff out also.

Maybe you would know a good place to fpv there