Portable 7-Band EFHW Antenna

@SP9TKW

Yes, I read that too, but I never saw data that backs this up. Is 85 degrees already a problem, or 45 degrees? In the last European SOTA event, I used a second mast (see photo) that kept the angle at around 90 degrees

Indeed, this is a great idea! This article is linked from within the ferrite core transformer article.

Update: for a wide frequency range, the transformed impedance looks for both winding ratios very flat, which is very nice and much better than the typical transformers with the standard winding technique!
Of course, all has to be measured by connecting a real radiator.
What I’m struggling with, is understanding how the toroid core is exactly wound. I don’t understand or can’t really get the picture of the following two sentences: “Crossing over the windings inside the core forming a winding per winding interlace. Wind on six interlaces turns.”. What is or how looks the winding interlace and what are interlace turns? It doesn’t help me to use Deepl.
Anyway, I would be very interested in the outcome!

@EA5M As Andy @MM0FMF proposed, there are many sources to get them from. I looked for a local source in Switzerland, but finally bought 10 from Mouser, along with capacitors and other bits and pieces to avoid the surcharge. The delivery was exceptionally fast.

73 Stephan

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