If you can, use a combination of resistors and coils to simulate the feed point impedance of the length of wire on a frequency of interest. Using some type 31 ferrite, wind a few (10 or so) turns of wire around it and put it in series with the resistor (dummy load) and see how the complex impedance seen by your analyzer changes. Notice how a 100 Ohm load offers a 2:1 SWR. Obtain a number of 50 ohm resistors and make a few different "loads" for your antenna analyzer to look at. But if it is you will see how that option compares to others. It may be possible to model the 9:1 Unun in Simsmith, I'm not sure. Plot the designs in SimSmith, a smith chart software, and understand some of the many matching networks that could be used to match it to 50 ohm coax. Your analyzer may not capture the sign of the complex impedance, but you can infer it. ![]() ![]() String up a long piece of wire and watch the resistive and reactive impedance change as the analyzer frequency changes. Obtain an antenna analyzer to take field measurements of various antennas. If you want to learn about this kind of antenna and matching network (the 9:1 transformer) I suggest you take the following steps: There is nothing magic about it, it's just an antenna that has been created with a bunch of compromises that end up being useful to some hams. Because it is longer than a quarter wavelength on the bands of interest, it will have a high impedance, and the 9:1 transformer will lower it to something that is closer to an acceptable SWR. ![]() For QRP power levels the ferrite will cost under $3. If you are not running 1000W you can buy the parts much cheaper.
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