Hello, my name is Mario, my callsign is IZ0IRH, i was looking for some info about this antenna. I have tried to model it by using MMANA-GAL and I assumed both 9:1 as a 4:1 balun, but I got very different values fo SWR. Almost surely I made a mistake in including the balun in the model, as I just put it as looking into Z0 = 200, and Z0 = 450 (referred to 50 Ohm) in the setup definition.
How did you model the antenna and the balun? Have you included also the reactive component (some R + JX) in the balun? Thanks a lot for any answer to help.
Modelled at 33ft above average ground, and assuming a perfect 9:1 balun (??), I see SWR(50)s of:
You could of course omit the balun and feed with ladderline.
Hope that helps,