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Help! Long range fpv arduplane platform questions

#1
For the last few months I have been cruising around with my Zohd Nano talon with an fpv setup that got me half a mile away. Over the weekend however, the plane and fpv setup stopped working, after it was run over by a plow. The esc burnt out (I was using the recommended voltage) and it glided right in front of a tractor and got churned up into bits and pieces. The receiver, battery, and servos were fine and it was on our property, so no real damage. But the event inspired me upgrade my platform. I have had this fx-79 for about a month now with the intention to turn it into an fpv platform with an autopilot on it. I have done a ton of reading about pixhawk boards so I ordered one and for the last week I have been having a blast exploring every possible function of it. I have all of my electronics tuned in and I am ready to mount everything to the plane. However, what I thought was going to be the easy part has been more difficult than anticipated. Right now I need to mount a gps, fpv system, and LRS (r9m 900mhz reciever) and I don't know how I need to space them out. I will put a list of my electronics below but I am struggling with how to plan this.I would like a gopro up front but it's not mandatory but I heard that they can mess up your vtx, and I planned on mounting the vtx about 4-5 inches high up front. The picture shows where I would like to place the camera and vtx on the nose but I am unsure if I need to mount it on the wingtip instead. The vtx receives power through an xt60 connector with a jst connector that runs off of it so it's powered by the main battery.

If I put the vtx on the wingtip I would have to run some pretty long leads to the camera and battery, wouldn't that create more unnecessary interference?
I have also read on the forums that 5.8ghz does not travel through epp foam very well, should I consider mounting it under the wing facing down?
IMG_1592.JPG IMG_1591.JPG
How well would the gps function where it sits currently? I planned on mounting it about 6 inches in the air on the stand it came with.
I also planned on mounting the RC reciever where it sits in the picture, is this enough distance from the other electronics?
IMG_1594.JPG IMG_1593.JPG
Two final questions that don't have pictures to illustrate them. If I mount my vtx or gps on a pole and turbulence forces those poles to vibrate, would those vibrations cause any sort of interference or would the small movements cause issues with vtx or gps? Finally, there is not a single toroid filter on the plane or really any sort of power filter on the plane. How important is it that I put some on and where?


This is my ground station BTW
IMG_1595.JPG

List of electronics on the frame

Plane: FX-79 Buffalo
RC Transmitter: Taranis QX7 with R9m LRS
RC Receiver: Frsky R9 reciever
VTX: TBS Unify Pro 32
VTX antenna: Foxeer Lolipop mmcx RHCP
Ground Station: Furious FPV Dock King
Video Receiver: Furious FPV True-D V3
Receiver Antennas: Immersion RC spironet patch antenna 8di RHCP and Immersion rc spironet 5.8ghz cloverleaf antenna (Diversity antenna combo)
FPV camera: Foxeer Razer Mini 1200tvl PAl
Flight Controller: Pixhawk PX4 with GPS, current sensor, buzzer, and safety switch
Motor: Durafly Tundra Motor
Prop: 12x6 Carbon Fiber prop, non-folding
UBEC: Hobbyking Skywalker 50amp ubec
Servos: 2x Emax ES08MAII 12g metal gear servo
Battery: 2x 3000mah 3s batteries in parallel
Action Camera: GoPro Hero 5

Any input would be appreciated, thanks!
 

PsyBorg

Wake up! Time to fly!
#2
Several things I would do.

First I would run the flight controls and motor as normal. Running the receiver antennas at 90 degrees offset pointing off the leading edge of the wing about an inch or so off the fuselage. This would be as simple as sticking a zip tie into the wing and hot gluing it at the desired angle. Then run the receiver wire out to those and heat shrinking the exposed part to the zip tie then trimming them back as short as you can without cutting the exposed antenna core. You could have one facing forward and one pointing up if you worry over perfect 90 degree. I run mine facing forwards on the same plane as my quad arms at 90 degrees with no problems for normal ranged flights. For the r9m long range antenna (I'll assume immortal "T" style) you can mount that behind where you have your go pro mounted in the picture.

Then I would run the fpv I would run one of the newer power distribution boards that have all the filtering and voltage regulators built in off a separate lipo. This will isolate any power based signal interference from the motor and esc. The vtx can be double sided taped to the upper wing to get good cool air. Water proof or heat shrink depending on your needs weather wise. then run the antenna for that to like the 3/4 width of the wing which ever side you use. then do the same with the GPS antenna on the opposite wing.

That separation should be fine for longer range as the antennas are not on the same plane and have good separation.

As for the go pro I would ditch that heavy camera mounting and go for a 3d printed style tpu mount used on quads to save weight and create less resistance as it would mount closer to the fuselage.

Here is an example of how I mount my receiver antennas to give you an idea. just find that 90 degree angle and push the zip ties into the foam leading edge of the wing and hot glue or super glue or what ever safe to use glue is used on that type foam.

IMG_0604.JPG
 

ElectriSean

Eternal Student
Mentor
#3
I have a similar wing - FX-61 Phantom, with none of the electronics really spaced out, all of it lives in the center section. Before I upgraded to Crossfire I was able to go 1.6Km with perfect video. After crossfire I was able to go over 5Km before the video gave out, running an old Lumineer 600mW VTx.

20180629_214819.jpg
 
#4
Several things I would do.

First I would run the flight controls and motor as normal. Running the receiver antennas at 90 degrees offset pointing off the leading edge of the wing about an inch or so off the fuselage. This would be as simple as sticking a zip tie into the wing and hot gluing it at the desired angle. Then run the receiver wire out to those and heat shrinking the exposed part to the zip tie then trimming them back as short as you can without cutting the exposed antenna core. You could have one facing forward and one pointing up if you worry over perfect 90 degree. I run mine facing forwards on the same plane as my quad arms at 90 degrees with no problems for normal ranged flights. For the r9m long range antenna (I'll assume immortal "T" style) you can mount that behind where you have your go pro mounted in the picture.

Then I would run the fpv I would run one of the newer power distribution boards that have all the filtering and voltage regulators built in off a separate lipo. This will isolate any power based signal interference from the motor and esc. The vtx can be double sided taped to the upper wing to get good cool air. Water proof or heat shrink depending on your needs weather wise. then run the antenna for that to like the 3/4 width of the wing which ever side you use. then do the same with the GPS antenna on the opposite wing.

That separation should be fine for longer range as the antennas are not on the same plane and have good separation.

As for the go pro I would ditch that heavy camera mounting and go for a 3d printed style tpu mount used on quads to save weight and create less resistance as it would mount closer to the fuselage.

Here is an example of how I mount my receiver antennas to give you an idea. just find that 90 degree angle and push the zip ties into the foam leading edge of the wing and hot glue or super glue or what ever safe to use glue is used on that type foam.

View attachment 150788
Thankyou for the incredibly helpful input, two questions. In your description of the rc antenna placement you mention two different antenna locations, on the wing and behind the gopro. I am only using the R9 for rc input, do you reccomend putting it on the wing or behind the gopro. Also, for the fpv setup are you suggesting puting the vtx on the wingtip and running power and video wires through the wing into the body, or placing the vtx close to the camera and running an extension cable to the antenna. Thankyou again for the help
 

Merv

Legendary member
#5
...Over the weekend however, the plane and fpv setup stopped working, after it was run over by a plow. ...
They just don't make stuff like they used to.

I've always put the Rx on one wing and the vTx on the other. There is about 12 inches separating them. I put the GPS on the Rx side. My Rx is non telemetry, so it is not sending anything, just receiving.
 
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#6
They just don't make stuff like they used to.

I've always put the Rx on one wing and the vTx on the other. There is about 12 inches separating them. I put the GPS on the Rx side. My Rx is a non telemetry, so it is not sending anything, just receiving.
That's true, I didn't consider the rx is just receiving.
 

PsyBorg

Wake up! Time to fly!
#8
You have 3 antennas on that set up the gps one sits low and flat and can be hot glued to the wing top. The r9 antenna is I assume the Immortal T type and has two arms. Putting that out on the nose with the arms sticking out either side gives it clear los to the ground with no worries of the foam degrading signal. The VTX antenna has a taller stance and can go as far out on the opposite wing of the gps unit and be put anywhere along the wing to keep roll axis balance. The VTX can stay close to the fuselage up on top as well to get better air flow as those create a ton of heat specially at higher power settings you will be using for long range. It can get hot enough to melt the foam if it was put inside the fuse with no air flow.

This is just what I would do. Keep in mind I have never done long range anything but I have played around with FPV enough to know what seems to work best when mixing antennas and various signals they use. Going by what others like Sean and Merv say because of their actual experience with it may be more beneficial or practical though.
 
#10
I have a similar wing - FX-61 Phantom, with none of the electronics really spaced out, all of it lives in the center section. Before I upgraded to Crossfire I was able to go 1.6Km with perfect video. After crossfire I was able to go over 5Km before the video gave out, running an old Lumineer 600mW VTx.

View attachment 150790
How did this improve your range? I though the crossfire system was an lrs for your radio.
 
#12
Could a low esr or lc filter work instead of having a separate power system for my fpv gear? Currently the vtx plugs into my main battery via an xt60 connector with a jst plug branching off.
 

PsyBorg

Wake up! Time to fly!
#14
The main reason for separate power is safety. If you power everything from one pack and have an issue your done. But when they are separated you have a bit of added security.

Say your esc dies on one battery the whole system is down. with separated video you can dead stick land or if no control at all you still have a way to know exactly where you went down. On the other hand if you go to far and your video fails you still have power to do RTH as the gps system controlling that is run off the pdb on its own voltage regulator..

That way each system is independent of each other. You CAN with a pdb power it all off one pack and still have that separation but that pulls milliamps much faster which is not so good for long range. Some pdbs can even supply you with osd information as well like main battery power amp draws and some even full blown osd's where you can choose what you want to see.