900MHz antenna position help

[Richrfl]

I am new to this 900MHZ frequency, and I have seen several radiation graphs of the "T" antenna, which seems to indicate that there is not too much difference in how you set the antenna in your plane. It is hard to me to digest that and therefore I would like to have advice from someone who has been using these antennas in non-carbon fiber, fixed-wing planes on how to position the antenna in the aircraft.

 

[thenated0g]

Are you going long distance?
If you are doing line of site i would say don't worry about it at all except to make sure the 2 antennas are 90 to each other. I think these are rated at 6+miles

 

[HENNY]

Are you going long distance?
If you are doing line of site i would say don't worry about it at all except to make sure the 2 antennas are 90 to each other. I think these are rated at 6+miles

The 900meg T antenna is in a dipole format so 90 deg orientation is not possible. If you run your TX at 100mw you will have lots of range.

 

[Richrfl]

Thank Henny, but my question is how this antenna should be located: Horizontal or Vertical? If horizontal, the dipole should be across the fuselage or in the plane longitudinal axis?

 

[Richrfl]

Are you going long distance?
If you are doing line of site i would say don't worry about it at all except to make sure the 2 antennas are 90 to each other. I think these are rated at 6+miles

Nat, you are talking about the 2.4GHz antenna. My question is about the 900MHz one. Thank you anways.

 

[thenated0g]

no im talking about the 900 mhz. Some of them you can orient the antennas as you want. I didnt see your T comment
Still that 900mhz, on line of site, i wouldnt worry about it. That thing will bounce around forever without issues even behind buildings.

As an example, i have a T antenna on a carbon fiber mini quad frame. The circle is where i was standing and the lines is the path i took, at like 2 feet off the ground. At some point there are 3 or 4 buildings in between me and the frame. No issues at all. This was in a flat horizontal setup.

 

[thenated0g]

 

[Richrfl]

no im talking about the 900 mhz. Some of them you can orient the antennas as you want. I didnt see your T comment
Still that 900mhz, on line of site, i wouldnt worry about it. That thing will bounce around forever without issues even behind buildings.

As an example, i have a T antenna on a carbon fiber mini quad frame. The circle is where i was standing and the lines is the path i took, at like 2 feet off the ground. At some point there are 3 or 4 buildings in between me and the frame. No issues at all. This was in a flat horizontal setup.

View attachment 20288

Thank you. You answered my question.

 

[HENNY]

Thank Henny, but my question is how this antenna should be located: Horizontal or Vertical? If horizontal, the dipole should be across the fuselage or in the plane longitudinal axis?

Across the fuselage will work fine for 900meg

 

[Richrfl]

Thanks a lot!!