Dipole antenna's, they are my favourite go to antenna, sometimes a rubber ducky but in my opinion self-made (and tuned) antenna's really go a far way. Even unchecked a good measured self made dipole usually outperform a wrongly selected cheap rubber ducky.
However remarks about the use of balun's in dipole antenna's are found here and there. A complex topic? A difficulty to implement? I thought it's a good thing to explore!

First and third antenna have balun. The other two are a classic build dipole using a PCB to mount the active and counter-ground part's of the antenna.
For myself I made up the following rule: Use a dipole with a balun on the receiver side, use a dipole without a balun on the transmitter side. If the power of the transmitter is expected to be less then 250mW a dipole with balun could be used on the transmitter side.
But what is a balun?
I'm not the best to explain, but
here is a nice write-up and where the idea and my first antenna's came from. Thanks kolins for my antenna's!
What I think it does, is limit the influence of the feeding coax cable, and in that way limit the influence of everything that is mounted beside the coax or on the airframe.
The chip I use is a
ETC1-1-13, it's
datasheet is to be found here. It is from the datasheet that I deduct that it's only to be used as a transmitter if the power is less then 250mW. Also it's only good for antenna's <3000MHz, so it's not to be used as a 5.8GHz antenna, I guess the chip is huge
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