Good Evening Bob:
Forget the Extra 10 feet, Anything above the Top hat will not Help. Put
the top Hat at the Top. Remember you were the one that had an 8 spoke
top hat and wanted to get it higher. You were my Inspiration and I
built an 8 Spoke top Hat 18' in Diameter with a Perimeter wire. On top
of a 70' Vertical the structure was pretty but horrible in the wind. I
started out with 5.5" Aluminum Pipe and ended up with 1.25" at the top.
So I took off the top Hat, and added three Sloping wires from the Top,
Each 49' long. They slope down and I now have a 160 meter vertical with
a perfect Match at 1.815 and an SWR of 1.5:1 across 70 KHZ.
I could not be happier. I did this on the recommendation of the rest of
the top band group to eliminate the base loading inductor, that was just
heating up the leaves in My Back yard.
So Far the results have been great, with most stations worked with a Few
Calls, and an improved efficiency.
Bruce N9BX 73
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160 meters is a serious band, it should be treated with respect. - TF4M
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