Topband: Inv-L wire in contact with tree branches

Gary Smith Gary at ka1j.com
Fri Sep 28 11:45:53 EDT 2012


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


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