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Old October 19th 12, 03:45 AM posted to rec.radio.amateur.antenna
J. C. Mc Laughlin J. C. Mc Laughlin is offline
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First recorded activity by RadioBanter: Jan 2011
Posts: 31
Default Wire antenna feed-line questions

Dear "gipy" (no call sign provided):

From what you have written, you must get a transmission line across a
"common area" (of something like 20 feet) to a long piece of property that
you control, and the only acceptable scheme is to bury the TL. For a
transmitted signal (I am assuming that you might be a radio amateur) a
buried, single wire TL of only 20 feet would result in little signal
reaching an antenna - so such a TL is counter-indicated. One could support
a twin-wire (two parallel wires) TL within a buried, larger-diameter
"plastic" conduit for 20 feet and not loose much, however you would have to
craft a scheme for supporting the twin-wire TL in the approximate center of
the conduit and the installation is likely to be provocative to other users
of the common area. So, coax it is. To have the coax have little loss you
must use BIG coax or not let the SWR get too large. By stages, arrive at
the conclusion you stated that the way to go is to use coax with a good
quality, autotuner at the far end (and a good ground). One can use a spade
(or one of many other tools including a larger knife) to slit the soil and
insert coax.

You will find it instructive, once you know the geometry of your long-wire
to use a computer program like EZNEC to get an idea where lobes are
expected. After you install, let the group know what you did. 73, Mac
N8TT

"gipy" wrote
I am in a situation where I HAVE to bury the feedline, there is no other way
around it. I have trees about 20 feet away from my home in the back, great
for swinging a long wire, dipole, whatever works but being that the actual
space between the trees and my home is a common area, I have to bury the
coax.
Placing a remote tuner on the other side would be a bit of a hassle but I
see its starting to look like the only way to go?
I got plenty of time, I just want to do this once and the right way.
Again, any thoughts appreciated and thanks to all who have posted, it is
turning out to be a very interesting thread.


J. C. Mc Laughlin
Michigan U.S.A.
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