The W8AOK G5RV
Bruce Cressler, W8AOK shows us how he uses
"Walnut Towers" for antenna installations.
Here he uses Mother Nature
in all her glory to assist with a big G5RV signal!
His method of
hanging antennas is for the birds!......and a WHOPPER
"As simple as the idea is of having a suspension line to
support the feed-point, I must admit I struggled with the old standard
method for several months before it occurred to me that I could have my
entire dipole suspended in free space (so to speak); and, for most
intents, eliminate the capacitive end loading with branches and leaves
that is so common with the generally used "tree method".
original antenna at this location was the same G5RV suspended as an
inverted-V from a drop-line hung over one of the highest limbs in a 65-ft
tall Walnut tree. The "Walnut Tower" worked well, but having the
feed-point near the tree's foliage during the summer months seemed to
drastically affect the antenna's loading characteristics. That
arrangement was later modified by stringing the dipole between the top of
the Walnut and a pine tree of similar height; however, doing so resulted
in the antenna feed-point sagging in the center from the weight of the
G5RV's feed-line and matching twin-lead.
Seeing the antenna
sag like it did is what made the first proverbial "light bulb" go
off. After stringing a suspension line between the two trees
where the sagging dipole once was, the center feed-point insulator was
secured to the suspension line and hoisted into wide-open spaces.
After pulling the suspension line tight and marking the coax feed-line
where it touched the ground; and, lowering and measuring the
distance between the feed-point insulator and the mark on the coax, the
exact height of the apex was known. Nylon rope was then secured to
the antenna end-point insulators; and, after calculating the correct base
line distance based on the now known height of the antenna feed-point, it
was a simple matter of driving stakes into the ground and securing the
end-point tethers to achieve a target apex angle of 105-degrees.
Having created a more-or-less perfect inverted-V, it was also
noted that two lawn mowing obstacles had been born (the stakes). As
the old saying goes, "necessity is the mother of invention", and, the next
"light bulb" went off. Out came the slingshot and two more treetops
became part of the final system seen above, and, the inverted-V G5RV
became a text book "flat top" G5RV suspended in free space." 73
"The Walnut Tower"
Photo by W8AOK
Visit the W8AOK WEB
Bruce sells a complete kit for
growing your own
"Walnut Towers". The kit contains
enough Walnuts to grow your own forrest
for only $19.95 plus P &
The only catch is that there is a long wait for the "Towers"
to grow.......usually about 70 years! Thanks Bruce for this fine antenna
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