What do you think of this modification?

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So I am working on a clean all inside mount of components. I mounted the iosdmini inside and now am working on mounting the video transmitter inside.

Mounted the vtx on the side next to battery, cut out the vents into a square where the heat sink can stick out a bit and get air flow. Plenty of room inside for video wires and antenna extension cable. Have about 1/4 inch clearance between the vtx and battery. Had to dremel out some parts of plastic support ribs to fit in the vtx but I am confident that I have not lost frame strenght. The vtx is secured with a ziptie and it is solid in place. The antenna extension cable ads some weight maybe 20grams.




I have also been thinking of placing the video antanna the farthes away from the main body as possible so that it can send out unblocked signal and so that it does not interfere with the control receiving line antennas in the legs. Drilled two little holes under neath one of the back motor mount area where a small ziptie can hold the vtx antenna out at the end of one of the back arms. I am working on where to place these two small holes to where the arm will keep most of it's motor mount strenght. On a second revision I placed the antenna even farther out of the arm, this gives me room to take the vtx antenna off / on when storing the phantom for travel.
Below is revised drill holes farther out to the end of the arm, now I can take off the vtx antenna.



Any thouths, Ideas, comments, concerns?
 

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Really nice ideas, moving the antenna out seems good, but I wonder whether it will disrupt downdraft airflow there. Is it possibly to mount it under a motor ?
 
Wow, I would think putting the antenna out on the arm, like that, would throw off the balance of the entire phantom...
 
Don't think you'll see any advantage in signal strength or interference by relocating the antenna. At the same time I don't see any issue with disturbing the downward thrust being below the arm but atlering the CG will definately effect control and will likely shorten battery life and put additional stress on the heavier arm's motor and ESC.

But enjoy your experimentation. I'm sure you'll let us know how it works out???
 
Hughie said:
Really nice ideas, moving the antenna out seems good, but I wonder whether it will disrupt downdraft airflow there. Is it possibly to mount it under a motor ?

Originally was thinking right under the motor but then I cant unscrew the antenna if needed, so I had moved it farther out. It does look better right under.
 

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mendezl said:
Hughie said:
Really nice ideas, moving the antenna out seems good, but I wonder whether it will disrupt downdraft airflow there. Is it possibly to mount it under a motor ?

Originally was thinking right under the motor but then I cant unscrew the antenna if needed, so I had moved it farther out. It does look better right under.

You may also be able to tie some toys on there too ;)
 
The Naza can compensate for the slight added weight out on the arm and balance the phantom. The H3-3D gimbal is pretty heavy and it is mounted towards an inch in front of center of gravity and the naza can handle this well.

I am trying this out on my old shell (i used locktite and it caused cracks and disolved some of the plastic, so had to get a replacement shell)
 
Motors may interfere with the signal at that proximity. Straight out the back past the battery is the location I've found to give the best results.
 
ianwood said:
Motors may interfere with the signal at that proximity. Straight out the back past the battery is the location I've found to give the best results.

what kind of interference?
 
Electromagnetic interference (EMI).

I can't see one advantage to what you have done regarding the antenna relocation.

(Possibly) lenghtened the cable to the antenna (never a plus).

Mounted the antenna near known sources of EMI (motor, esc).

Offset the CG by putting the antenna as far from the CG as possible (at end of arm).

Added holes to an area where some have reported stress cracks appear in and around the motor mounting holes.
 
Good points, may reconsider.

Right now my main concern is drilling holes near the motor mount area. I need to find another way to mount on the arm.
 
N017RW said:
Don't think you'll see any advantage in signal strength or interference by relocating the antenna. At the same time I don't see any issue with disturbing the downward thrust being below the arm but atlering the CG will definately effect control and will likely shorten battery life and put additional stress on the heavier arm's motor and ESC.

But enjoy your experimentation. I'm sure you'll let us know how it works out???

I agree. WB4PSM 73
 
mendezl said:
Good points, may reconsider.

Right now my main concern is drilling holes near the motor mount area. I need to find another way to mount on the arm.

Another possibility is a zip tie fastener. It is square and has adhesive on the back, with two slots for a zip tie to go through. You will probably have to trim it to fit.

Downside: It is light, but being that far away from the CG, it might add to the inbalance.
 
mendezl said:
Good points, may reconsider.

Right now my main concern is drilling holes near the motor mount area. I need to find another way to mount on the arm.


I would ask why are you so driven for this?

What is your expected improvement?
 
When flying out lets say 1000meters, on the way back when the phantom is heading towards me, the gimbal/gopro is between me and the vtx antenna (if the antenna is mounted in back by the battery.) There is some signal loss and lower quality video. Was thinking where can I mount the antenna where it is most out in the open. Out on one of the arms the antenna has a clear line of sight in most orientations.

Some of the rc fpv plane guys recommend placing the vtx antenna on opposite wing from the control antenna. I understand quadcopters are smaller, but was thinking where can the vtx antanna be mounted farthest from the little control receiver line antennas.

Installing the transmitter inside looks nice and clean.

I showed my wife and she said that simple is better. Dang.
 
OK then.

I can relate to the clean appearance.

Hope the internal mount stuff works.
 
Just thought of using a propeller guard. The outside guard part can be cut off leaving just the roundish mount part that screws on. Could mount the antenna to that and then screw that in. No drill holes.

Even better would be the clip on 3d printed prop guards. No screws, no drills.

So I emailed Tony with FPVLR. I bought antennas from him. There are some legit issues you all have mentioned, if he also says it is a bad idea then I'll scrap this project.
 
Prop guards are a disaster waiting to happen IMHO. They do disturb the downdraft and hanging an antenna off them can only make a bad situation worse.

Really pleased you are pushing the boundaries on this though. That's how good things happen.
 
N017RW said:
Electromagnetic interference (EMI).

I can't see one advantage to what you have done regarding the antenna relocation.

(Possibly) lenghtened the cable to the antenna (never a plus).

I'm curious why adding an extension cable to the antenna is never a plus? some signal loss?

I'm asking because I ordered a SMA extension cable. My antenna points down behind my battery. The issue is when I rotate at a distance the camera/gimbal blocks the Antenna where it is and I get some signal breakup. I planned to let it hang down a bit longer with the cable so it would not be blocked when rotated. I would take off from some kind of platform so the antenna's few inches extension wouldn't touch the ground. Is there some issue I should be concerned about by using a short extension cable?

Thanks for the comments. :)
 
knuckles said:
N017RW said:
Electromagnetic interference (EMI).

I can't see one advantage to what you have done regarding the antenna relocation.

(Possibly) lenghtened the cable to the antenna (never a plus).

I'm curious why adding an extension cable to the antenna is never a plus? some signal loss?

I'm asking because I ordered a SMA extension cable. My antenna points down behind my battery. The issue is when I rotate at a distance the camera/gimbal blocks the Antenna where it is and I get some signal breakup. I planned to let it hang down a bit longer with the cable so it would not be blocked when rotated. I would take off from some kind of platform so the antenna's few inches extension wouldn't touch the ground. Is there some issue I should be concerned about by using a short extension cable?

Thanks for the comments. :)


Don't mean to scare you. The loss is minimal and do not be concerned. If it is required do not worry but sometimes mods are done which don't actually result in benefit. Do what you must.
 

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