Best antenna alignment?

[Wanderer]

I am currently a bit confused... DJI posted a video regarding proper antenna alignment.

My own experience tells me that the best transmission is received, when both antennas are aligned 90 degrees to each other. However, according to the DJI video, this is bad:

Fig.A

Instead it is recommended to do it like this (the funny thing is: you CAN'T DO SO with the Spark RC):

Fig.B

Also, the long side of the antennas should always point to the Spark, like this:

Fig.C

But then you would have to manually adjust the antennas each times your Spark is directly above you, because it gives a poor transmission upwards. So wouldn't it be best to align the antennas like this?

Fig.D

By doing this, the antennas would fire in both directions - to the front and above, or not?

But DJI suggests to align BOTH antennas parallel. Why that? Isn't one antenna enough for one direction? Is there any kind of signal boost if both antennas are aligned into the same direction? I don't think so.

I always tought the benefit of having TWO antennas is to being able to align them in different angles (ideally 90 degrees) to have a good radiation spread.

So I am confused... should we align both antennas into the same direction? Or use a 90 degree angle here? Or pointing one up and one to the front to have good transmission for both, short and long distance? What's your practical experience with the Spark here?

 

[tomek1221]

folow

 

[Zookeeper]

Position should be as fig c. The spark should be at a right angle from the flat faces at all times. The radio signals propagate in a sort of doughnut or bagel shape. The ends of the antennas and a line straight out from them are in the hole and if spark drifts in to that area it will cause signal drops for sure. So keep the antennas flat faces pointing at your spark, as spark rises then raise the controller to maintain that orientation..

 

[rich777]

Each antenna does a different thing. One transmits the uplink and one receives the video data downlink so they don't work together as a paired team.

 

[aviscomi]

According the page 38 of the Spark Manual:

 

[DesertWindAero]

I am currently a bit confused... DJI posted a video regarding proper antenna alignment.

My own experience tells me that the best transmission is received, when both antennas are aligned 90 degrees to each other. However, according to the DJI video, this is bad:

Fig.A

Instead it is recommended to do it like this (the funny thing is: you CAN'T DO SO with the Spark RC):

Fig.B

Also, the long side of the antennas should always point to the Spark, like this:

Fig.C

But then you would have to manually adjust the antennas each times your Spark is directly above you, because it gives a poor transmission upwards. So wouldn't it be best to align the antennas like this?

Fig.D

By doing this, the antennas would fire in both directions - to the front and above, or not?

But DJI suggests to align BOTH antennas parallel. Why that? Isn't one antenna enough for one direction? Is there any kind of signal boost if both antennas are aligned into the same direction? I don't think so.

I always tought the benefit of having TWO antennas is to being able to align them in different angles (ideally 90 degrees) to have a good radiation spread.

So I am confused... should we align both antennas into the same direction? Or use a 90 degree angle here? Or pointing one up and one to the front to have good transmission for both, short and long distance? What's your practical experience with the Spark here?

Can you post the link to the video?

 

[msinger]

Here's the video:

 

[Wanderer]

Each antenna does a different thing. One transmits the uplink and one receives the video data downlink so they don't work together as a paired team.

Ah, got it. This is why both antennas (their long side) should point to the Spark and why they should NOT aligend in a 90 degree angle to each other. Didn't know that each antenna does a different thing (uplink / downlink).

Very useful, thx!