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Old November 29th 06, 11:12 PM posted to rec.radio.amateur.antenna
Merlin-7 KI4ILB Merlin-7 KI4ILB is offline
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First recorded activity by RadioBanter: Oct 2006
Posts: 46
Default Tower height question (moved thread from tower pro NG)

I will be moving my QTH next year some time and am planning my new tower.
I need to figure out the minimum height of the tower to work 10 thru 80
meter bands and 160 if possible. The tower I have now is only about 42' tall
and I have good results from it. However I have nothing else to compare it
with.
I can put up a dipole for each band but I think that there would be a lot
of interaction between them.
Below is what I have now and I want to improve upon it however I want to
limit my antennas to wire for now.
What height do you think I will need and at what height should I place each
dipole? They will need to be inverted a bit.
Lets say that with the tower in the center, the ends of the wires and / or
rope that holds up the wires is 20feet up and 120 feet from the center of
the tower on each side.
X20'-------------tower-------------20'X



I like to play with wire antennas but let me explain my fan dipole in
detail.
It has 3 elements a 66' a 33' and a 16' on each side of the feed point with
an airwound choke at the feed point. It is not a normal fan. The wires are
hung under each other with the longest on top and the shortest at bottom.
They are spread apart 12 inches by pvc pipe, the first spreader is 18 inches
from the feed point. The feed point is about 40' up and the end of the 66
footer is about 18'up. So the ends of the shorter wires are higher since
they are hung under the 66 footer. (I hope I explained that well enough) I
also have many buried radials that are also tied into the chainlink fence
that runs about a square block (all my neighbors fences are tied together)
I have worked Germany and several other places in Europe with it but I know
I could do better with everyone's help here.

I want to do some long DX work limited to 100 watts on every band That I
can.

The tower will be on a 1 acre lot but my sister owns 6 acres behind my lot
and my parents own 2 acres to the right of my lot. So I have plenty of room
for wire antennas and buried ground radials.

I can use one ladder line feed but the rest would need to be lmr 400 for hf
and lmr 600 for uhf /vhf

Do you all think that I could get by with a 80 foot rhon 25g?

Ideas?

One more question, how will the guys effect the wire antennas? I do not
think that I could afford poly guys.



73's Joe
KI4ILB