Small, light, and efficient 49:1 and winder that fit inside the KX-2 case.

I wanted a smaller, lighter antenna wire winder with a case for my unun that uses a tiny core for extra lightweight efficiency. I also wanted the case to not require hardware to hold the lid down. I think I accomplished all my goals with this one.


Nice design. If someone is looking to make one, Sotabeams sell the core, without the burden of digikey’s postage rates.


Good find! That’s awesome!!!


This is a cool build … I have been wanting to build my own EFHW and now I have the motivation and the plans to do it!

Thanks - Chris


Thank You! I hope it works out!

I’ve had good luck with this product. Just add a wire of appropriate length and you’re good to go. I mostly use it as a 40 meter EFHW and my KX2 ATU matches it on all the bands that I care about.

An efficiency of 95% would be all too nice, hi.
Apparently a mix-up when reading from the spreadsheet of MM0OPX

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I wasn’t using his spreadsheet, but when I went back and looked, it turns out I did misinterpret my own data. It’s more like 88-90 percent efficient by my calculations. Can’t revise a YouTube video. Oh well.

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