We usually look for a high or open spot to stand when flying long-range FPV to avoid our signal being attenuated by obstacles. This allows us several kilometers of range in the countryside without needing a directional (high gain) antenna. Sometimes you might not have such an ideal spot to fly from though, so it helps to use an antenna with a narrow beam to focus that weak signal.
We attached a handle, video receiver, and battery to the back of this Circular Wireless helical antenna so it could be held by one person and manually pointed toward the copter, while the other person flies FPV:
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| Circular Wireless Heliaxial 1.3GHz antenna with video receiver, battery, and handle mounted to back |
On the video tx side we used the
Circular Wireless Skew Planar Wheel. In our long-range mountain flying test, we started from a low point near the base of the valley, in a location with obstacles such as trees and buildings. We were still able to fly over 2.0 km away with a clear video signal.
Flew FPV in the mountains of Changhua to a peak 2.0 km away.
A drawback of the Heliaxial is that it is bulky, needs to be transported carefully to avoid breakage, and is probably too heavy to be mounted to most antenna trackers.
Fortunately, Circular Wireless has come out with a new
Circularly Polarized 1.3GHz Patch Antenna that should be much more convenient. We plan to test it out on a flight soon!
