Hello,
I recently modified my old 204BA using the BV204CA file (YW, Yagi for
Windows by N6BV) from the ARRL Antenna Book.
I moved Driven Element and Director 1, changed the element tip lengths
where necessary and changed Hairpin match length according calculations.
According to the computer model the calculated SWR is 1.09:1 on the
resonant frequency of 14175, and 1.40:1 on the edges: 14000 and 14350 at
the 80' height.
Hairpin spacing that used is 12 inches (different from the original one,
which was 6 inches).
In reality, I have SWR of 1.05:1 on 14090, which appears to be my new
resonant FREQ now, and 1.6:1 on 14000 with 2.6 on 14350.
Why is it so narrow?
What am I doing wrong? Should I use original hairpin rod spacing of 6"?
Old variant of this antenna was wider (better broadband)
Any advise would be greatly appreciated.
--
73, Yuri VE3DZ
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