>From the website:
"A full wave antenna would usually have about 4K ohms at the feed point.
Pretty hard to match a 50 ohm or even 300-600 ohm load to that. With the
addition of the capacitors we can have a full wave antenna and have the feed
point load around 200-500 ohms, or, something we can work with."
Seems to me it would be less complex and more maintenance-friendly to vary
the feedline length of the open-feeder or ladder line to achieve a
transformation from 4K-ohm to 50-ohms. In fact, if 600-ohm line is used, as
the line length nears an electrical quarter-wave, that 4k-ohm Z is brought
down easily. The 600-ohm line VSWR remains constant along the line at
roughly 6:1, but the 50-ohm VSWR will reasonably approach 1:1. If a
quarter-wave section is not convenient, then add another 1/2 wave section to
the quarter-wave section as an alternate line length.
"They are broad band. The 40/80 meter version is under 1.5:1 across all of
40 meters and at or under 2:1 across all of 80. The 20/40 is even better!!
This is all on a single antenna!! No tuner should be needed!"
Is that broadbanding coming at the expense of resistive losses? If so,
another argument for a simple change in feed-line length to achieve an
efficient result.
Paul, W9AC
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160 meters is a serious band, it should be treated with respect. - TF4M
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