Hi Gary,
I have had good luck with #14 ga. teflon coated, silver plated, stranded wire
from a flea market. Would like to find more of this as it loves treetops.
I tie a supple branch or make a rope inverted "T" configuration between to 2
supple
branches at the antenna far end which acts as a shock absorber for the the
endfed wire when the mighty wind blows and the heavy ice coats, as it frequently
does here in the hills of NH.
73
jim / W1FMR
--- On Fri, 9/28/12, Gary Smith <Gary@ka1j.com> wrote:
From: Gary Smith <Gary@ka1j.com>
Subject: Topband: Inv-L wire in contact with tree branches
To: topband@contesting.com
Date: Friday, September 28, 2012, 11:45 AM
I'm fortunate to have a nice radial
assembly of aprox 50 130' radials & half
of them on a salt marsh with the rest over
boggy ground. Unfortunately I have no way
to put up a pulley system with relief on
one end and the antenna in open air.
I use 6 & 8 strand ribbon "CAT wire" which
was used indoors for running computer and
phone wire. I got several miles of it at a
cheap price on ebay. I used that for my
radial wires, soldered at both ends and I
also use it for my elements. I have an
inv-L for 160, an almost full length
vertical for 80, a 40M & 30M vertical all
using the same radial bed. I used to have
a butternut for 20-10 meters but found I
heard and transmitted better using one of
the aforementioned wires instead for the
higher bands. I use a PVC cannon to shoot
a projectile over the tallest tree and
raise the antennae that way.
The verticals are no issue, they remain up
and give no problem. The problem is on 160
where the best I can do is aim for a hole
in the tree tops and shoot the projectile
through it & over the tallest tree I can
get to. I tie down the distant end with
the entirety of the wires elevation
resting on tree branches. Being on the
ocean's edge there is considerable tree
movement all the time and yearly the wire
frays and breaks close to midway. It came
down this week. I'm guessing the plastic
layer of the ribbon is not UV proof and
that allows the outer insulation to peel
off exposing the 24 gauge solid wires to
the sun and their insulation to wear &
break off. The CAT wire is quite sturdy
when first used but it is made of many
fragile parts.
All that to say; since I have no choice
but to run the wire over the tree tops,
what would be a better wire?
Copperclad would probably be more durable
but the contact with the tree branches on
exposed wire would be no good. Enamelled
copperclad would soon have the enamel worn
off & there would be direct metal contact
to the branches. I can't find any of the
old copperclad two element telephone
wiring around here with UV proof & durable
insulation as the phone company won't give
it or sell it privately when they take it
down. I looked at the wire Home Depot has
and the stranded wire doesn't seem to have
a tough insulation.
I'm putting another 8 element wire back up
today as there's some pacific DX I need on
160 that's coming to a close but I need to
put something better up that I don't have
to keep replacing 1-2 times a year.
Thanks
Gary
KA1J
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
|