I have two almost vertical dipoles made from old Mor-Gain 80/40 antennas.
They are hung high in trees with the bottom 1/2 sloping slightly in the
direction I desire. One slopes to the NE and the other slopes to the WSW.
The top is about 77 feet and the bottom is 14 feet. LB included my vertical
dipoles on his web page under SCV. They are about 60 feet apart and K4SQR
thinks I need to phase them for best results.
The NE (the first one) was put up years ago just before the D68C Dxpedition.
When (on 75) they called for 4's I was the first one through. I worked
FT5GA, S01R, K7ZZ at ZA and others with the antenna. I have worked JA, ZL,
and VK on the other.
These are DX antennas although they do quite well to Central America.
Compared to a dipole at 55 feet Stateside is 15DB stronger. So they are not
for the ARRL SS or Sprints. I had to move the WSW vertical as it really
messed up the 40 meter beam pattern when only 20 feet away from the beam.
Now its almost 40 feet. Van W4GIW made a vertical dipole for 75 out of
ladderline several years ago based on Dave Ingram CQ article. Van found
that the half size (234/F)was not correct and found that 280/F was correct
to get it set to 3795.
For those who are not familiar with Mor-Gain dipoles they are full size 40
with a full size 75 or 80 wrapped around the 40 and open at the ends. They
are 66 feet for the 75/40 and 69 feet for the 80/40.
73 Dave K4JRB
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