you have rip out or cut off your FrSky XSR receiver antenna
In this tutorial, you will learn how to make a successful frsky xSr replace the antenna, in which case you have torn or cut off your xSr receiving antenna.
First of all, let's look at which type of antenna and the length of antenna you need to replace your bad antenna.
How to choose the right antenna
The xSr receiver uses an antenna called a monopole antenna, which consists of a core for transmitting information and a metal mesh covered with ground.
Real frsky antennas are highly recommended.
Ideally, in order to get the strongest signal received by our antenna, we must have an antenna length in which the inductance and capacitance are equal, because the additional capacitance or inductance will lead to performance degradation.
Choose the right length of our antenna. In order to successfully replace the frsky xSr antenna, we must consider the wavelength of the radio wave. The resonance frequency is a multiple of the signal wavelength. The inductance and capacitance of the antenna are equal. In our example, we will use a quarter of the length.
It is also important to remember that when we discuss calculating the length of the antenna to make a successful frsky xSr replacement, we calculate the length of the active element, in other words, the length we are looking for for for a braided shield that is not covered by the core.
Therefore, when the xSr is tuned to 2.4 GHz, the quarter wavelength is 31.2mm long, calculated from (light speed / (2.4GHz)) / 4 = 3.1228381cm.
As we can see, in theory, the ideal active element length is 31.2 mm, but with the xSr receiver not making the same as it has some inductance in the purpose, the optimal length of the active element so that a successful frsky xSr replacement antenna does not degrade the performance will be 26 mm, which is the stock antenna length.
In addition, we also need to consider the type of antenna connector, which can be IPEX connector, you need to cut it later, or you can buy a direct welded antenna, which is the most convenient choice.
To sum up, in order to make a successful RX antenna, you need a monopole antenna with a 26 mm active element. It is worth noting that the shielding wire can be any length because it does not radiate.
How to replace antenna
The first thing, in order to make a successful frsky xSr replace the antenna, is to start by unsolder the old antenna you want to replace.
Now, if you have purchased an antenna with an IPEX connector for frsky xSr, you will have to cut it carefully and prepare to weld it, but if you have already purchased a direct welded antenna, you can skip this step.
You can peel off the plastic jacket about half a centimeter. In order to make this easier without cutting the cover, it is recommended to burn off the plastic with a lighter so that it can be easily removed or cut off with a precision knife.
Then, in a way, pull out the exposed shield, twist it a little, and tin it. After removing a millimeter of transparent enclosure to avoid shielding contact with the core, you are done and you are ready to weld the antenna directly to make a successful antenna replacement.