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Don't you just love it when something works! I took down my multi-band end fed half wave (EFHW) antenna last weekend and replaced it with a home-made 40m off-centre fed dipole (OCFD).
The EFHW worked, but I was never happy with the performance. This may be due to the inverted L configuration or the compromise 49:1 ferrite-based Un-Un. Either way, I felt I was missing out on some DX and was keen to try something else for the Autumn/Winter.
The 40m Windom is about 66ft long and has a home-made 4:1 Guanella balun made with two ferrite cores. It is fed at the 41%/59% point so it covers 40, 20, 15 and 10m with an SWR below 3:1 and the other HF bands with an ATU.
The apex is at about 8m with the ends down to about two metres, so not ideal.
Nevertheless, in back-to-back WSPR tests it proved to be better than my W5GI dipole that goes over the roof by about 7dB on average. This was good as the EFHW was mostly down on the W5GI.
Anyway, I thought I would leave it running on 20m WSPR for 24 hours to see what it could pick up. This was with zero sunspots, but a Kp index of 1. I was delighted to see that I had been picked up as far afield as Japan, Australia, Alaska, Antarctica and Brazil. The furthest west I got in the US was Utah.
So, I'm a happier bunny. I might return to the multiband EFHW one day, perhaps looking at different ferrite mix configurations for the Un-Un, but for now I'll stick with monoband EFHWs with tuned iron toroid/capacitor matching units that work well.
The OCFD can stay up for a while - you know that the best antenna you can have is either the one you just took down, or the one you are going to put up, not the one you are using!
Nice to know you are getting a better result. But you don't declare the WSPR power you were using. Consulting the WSPR database, it's found to be 37dBm, or 5W. It's not remotely surprising that you are getting global coverage on 20m with that much power. It would be much more useful and instructive to use 1W or less.
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