Aircraft Antenna Mod

[droneuser]

Well it seems to me that the stick antenna is more like a panel antenna and not a TRUE Omni antenna cause when the bird is facing me I notice a signal is not as good as when the bird is not facing me so to me that is a panel antenna

 

[beanbubba]

Well it seems to me that the stick antenna is more like a panel antenna and not a TRUE Omni antenna cause when the bird is facing me I notice a signal is not as good as when the bird is not facing me so to me that is a panel antenna

It is positively an omni antenna in the neighborhood of a 3-4 dBi gain. However, they put a reflector in the antenna housing that I have never seen used in this fashion. I suspect that this makes up for the rear swept antennas in an attempt to improve range to the rear of the AC. This would be similar to the dish in a dish antenna.

 

[droneuser]

but by doing that wont that act more like a panel antenna the a Omni antenna?

 

[beanbubba]

but by doing that wont that act more like a panel antenna the a Omni antenna?

This is what a low gain omni coverage antenna roughly looks like. They are designed to be used in a vertical position. When they are tilted, you can see the effects below.

This example is from Lolo's experiment by flipping the factory antennas 180 degrees in their mount under the motors. It has been proven to level out the coverage difference from the bird flying away versus flying home.

 

[droneuser]

ahhh ok so if I was to put a connectors in back and install a 6 dbi antennas ( no amps) that should really help overall not just when flying away or home

 

[beanbubba]

I have been wanting to do this mod for a while and I am in the middle of several bird side configuration/testing. Having fixed SMA/RP-SMA connectors is a dream when you are constantly changing gear out (not to mention avoiding stressing the fragile U.FL connectors).

I have some custom length coax on order to tighten this mod up even more.

 

[fileophile]

Looks good Bean! I'm planning to do something similar, but with QMA connections instead of SMA. (I just love me my QMA!)

 

[beanbubba]

Looks good Bean! I'm planning to do something similar, but with QMA connections instead of SMA. (I just love me my QMA!)

Good luck! Please send pictures when complete.

 

[milchoni]

I’ve red the whole theme. Tx/rx amplified on the rc and the aircraft. No wires. Everything is hidden inside. 2 hours work.

 

[beanbubba]

I’ve red the whole theme. Tx/rx amplified on the rc and the aircraft. No wires. Everything is hidden inside. 2 hours work.

Very cool milchoni!!!

Do you get any GPS errors in flight? I have had problems sometimes putting the amp that close to the GPS receiver.

Please share your experiences, thanks.

 

[beanbubba]

Very cool milchoni!!!

Do you get any GPS errors in flight? I have had problems sometimes putting the amp that close to the GPS receiver.

Please share your experiences, thanks.

I would love to see some internal photos of your mod too.

 

[milchoni]

Very cool milchoni!!!

Do you get any GPS errors in flight? I have had problems sometimes putting the amp that close to the GPS receiver.

Please share your experiences, thanks.

Today I had no problems but it was windy and tomorrow I hope I can test it again.

 

[milchoni]

No problems! 15 satelites and full bars.

 

[beanbubba]

No problems! 15 satelites and full bars.

Nice. Did you take any internal pic's of your mod?

 

[BigMotor]

Nice. Did you take any internal pic's of your mod?

Nothing from milchoni yet?

 

[beanbubba]

Copied from the antenna mod thread:

I found this cool antenna that has dual 19 dBi gain antennas in a single panel and they are properly positioned with polarization 90 degrees offset from each other (how its supposed to be done if you want to take advantage of MIMO).

The "cool" part is that it has an integrated housing for whatever electronics you want to mount inside it. And it's big enough to hold two "8W" amps plus a battery of your choosing. I found it from various suppliers between $50-$100 and that's a steal for this style product. It's also used by a few notable commercial Wi-Fi access point vendors and thats a very good sign of its quality. They also state ALL the radio spec's on their website unlike some of our other suppliers that have been mentioned in this thread.

Antennas - ITElite

Anyway, for those of you traveling around with 2 big panels in your rig, you can replace them with this single unit and hide all your amp's, batteries, and cables in one enclosure. And it comes with a universal mounting kit. I can't think of a possible better solution for us traveling pilots and our boosting kits.

BTW - this is the highest gain antenna you will find in 2.4 gHz before they get freakishly large in physical size.

 

[fileophile]

So Bean, you are saying that this single (dual ported) panel antenna can replace the dual antennas on the controller? So it can act as both the receive and transmit/receive antennas?

I don't follow this with my limited radio knowledge. The dual polarization (90 degrees out of phase with each other) in the panel antenna I understand, but don't the RC antennas share the same polarization? (I.e. they both point up, vertical polarization). What informs the drone that the panel antenna's polarization has shifted 90 degrees for one or the other antenna?

 

[beanbubba]

So Bean, you are saying that this single (dual ported) panel antenna can replace the dual antennas on the controller? So it can act as both the receive and transmit/receive antennas?

I don't follow this with my limited radio knowledge. The dual polarization (90 degrees out of phase with each other) in the panel antenna I understand, but don't the RC antennas share the same polarization? (I.e. they both point up, vertical polarization). What informs the drone that the panel antenna's polarization has shifted 90 degrees for one or the other antenna?

That is a long and detailed discussion on MIMO radio technologies and outside the scope of this thread.

MIMO - Wikipedia

But yes, you can replace both RC antennas with this single dual element antenna and expect good performance (caveat is that the RC left port MUST be on the port labeled vertical polarization and the RC right port on the port labeled horizontal polarization).

 

[fileophile]

Ok, good to know. Thank you.

 

[fileophile]

I put up a 40’ mast this weekend to hang some panel antennas on for Mavic flying, and am wondering about some things:

I have a couple of these: 2.4 GHz Flat Panel Directional Antennas . Do I need to use them both? The original plan was to use one for each of the RC antenna inputs but it sounds like I could get away with just using one for the left side input and not use the right side at all.

If I do need 2, is it best to mount one with vertical polarity and the other sideways to it (horizontal polarity)? Which one goes to the left side RC antanna input?

Does this need some kind of grounding?

I know these are high-gain directional antennas so need to be pointed in direction of flight. How far off this direct-line can I fly? 10 degrees off, 20 degrees off, ??