I have two Mor-Gain short dipoles mounted vertically. The top part is pure
vertical and the bottom half is sloped (65 degrees) to the NE on one and to
the SW on the other. The antennas are elevated 15 feet or so off the ground
and fed in the center with the coax running close to right angles away from
the vertical dipoles.
K4TWJ ran an article on using ladderline for half wave verticals in 2003 in
his CQ column. Van W4GIW and I saw this and we found that Ladderline worked
OK but was roughly 280/Fmhz rather than 1/2 size. The Mor-Gain has a 40
meter dipole sown the center and the 80 spacing between wires is about 4.5"
rather than 1" for ladderline.
The vertical dipole is down on close in stations (say within 1200 miles)
usually. But I have seen 6 to 10 db difference on DX. I turned the NE
vertical dipole slope toward the E and worked D68C on the first call when he
first called for 4 land. I used the same antenna to work 3B9C with 100
watts on 75 SSB. W4GIW ran some tests on his laddereline vertical dipole
and he was consistently 10 db better on say OK2 or LU.
A variation of the vertical dipole is the K8UR antenna (really the W9LT
antenna). This is a dipole mounted as a sidewise V )as >). This makes a
pure vertical. I have a small Spi-Ro 100 foot 160 dipole that I quickly
strung up last year and on SSB worked CN2R, D4B, EA9, IH9, and several G's
and DL's. Any vertical dipole can be phased too. Jim K4SQR says I could
phase my two Mor-Gains. KC1XX and K3LR have phased the W9LR/K8UR as a four
square dipole array.
If you ground mount the half wave it has to be matched and requires a ground
system this may the real problem with poor performance.
The higher you can elevate them the better! I feel 30 feet on 80 and 60
feet on 160 is near optimum. 15 feet on 80 and 25 feet on 160
is the least required.
73 Dave K4JRB
Trying to DX on 160 and 80 on a small lot
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