How to best orient the antenna on your RC transmitter?
Summary
It seems like everybody at the flying field points their transmitter antennas in a different direction. I’m talking about the spread spectrum or 2.4 GHz radio systems. These antennas have a blind spot at the end of their tips. They also have the strongest signal at about a 45 degree circle around the tip.
Pointing the antenna straight up or forward risks pointing the end of the antenna directly at the model. I have noticed that folks either lean their transmitter forward or back and they do not seem to know they are doing it.
Don’t expect to be able to notice if your model loses the transmitter signal. If it is flying straight, it will continue to fly straight. But if you are doing a maneuver, it will manifest itself as a glitch.
Pointing the antenna at the ground is literally throwing away the strongest part of the signal. I do not recommend doing that either.
I point my antenna to the side because that seems like a reasonable compromise. I will never be pointing it straight at my model. There is good signal strength always reaching the model.
There is another very important reason why pointing the antenna to the side makes sense. I do not have to move it when I put my transmitter away! I have heard way too many reports of transmitter antennas breaking internally because they were flexed too many times. For most brands, you have to send in the transmitter to have it fixed. That can be a real bummer in the middle of the flying season.
I suppose that with the new fixed “diversity” transmitter antennas, this whole point is moot. But until we all upgrade our transmitters, just point it to the side.
Related posts:
LiPo Battery Care Tips
Tip: Is your Model Airplane Tail Heavy?
Tip: Is your Model Airplane Nose Heavy?
Landing in Gusty Winds
Puffed RC Battery Pack?
Best and Worst Places To Be When Flying
How To Flight Test A New RC Model Airplane
Spectacular RC Airplane Crashes
What is the Best Cruise Airspeed?
Tracking Battery Pack Charge State
Epoxy Gluing Tips for Model Airplanes
Upgrading to a Bigger RC Battery Pack
Your antenna position make lots of good sense. Thank you
I was half expecting somebody to disagree with me, but so far all the comments and emails say “right on”.
Daniel Trujillo liked this on Facebook.
I got used to not having to pull the antena out of my 2.4GhZ transmitter, then got out an older model using a 72MhZ transmitter and didn’t realize untill after I was walking out to where it crashed that I forgot to pull the antena out.
What I find odd is that it does not happen more often! LOL
Your article says it applies to 2.4 Ghz. May we assume the same goes for 72 Mhz?. Yes, it is not as likely to point the antenna at the A/C, but it can happen.
Yes, the same concern applies.
Teory indicates that polarization of this antennas are almost circular. Propagation of signal map seems a “donut” with the axis of antenna on center of hole and perpendicular to maximum circle of donut. They have most of power (and maximum distance) in plane at 90º from antenna axis and very little propagation on atenna axis. If you have the antenna straight and pointing to the model, this is ther worst position and your model loose signal at few meters. The position you sugest is a good compromise to maintain signal on better zone, but you will have very little power at right and left of you; but i think you dont see the model by side but in front.
Yes, I agree.
Another good position is 90º up from the radio, it have the same advantages as lateral 90º you suggest, but you can loos signal when the model is passing haigh over you (if you maintain the radio TX horizontal)
Right. I see too many pilots lean forward their transmitters when they fly. I may be one of them! Their antennas would be pointed straight at the model, and I do not think they would even realize what they are doing. That is why I recommend pointing the antenna to the side.
A last think about signal…when more dbi on a omnidirectional antenna (greater antenna), less signal on axis and more “plain” is the “donut”, but with more diameter (signal goes more far).
Better signal is reach when both TX and RX antennas are paralel, but this is impossible to maintain alwais right on a 3D moving system as a aeromodel.
That’s right. Having the antennas face each other from the side is the best situation.