For a nasty application like that, look at Wireman #531 and Wireman
#547. The coating is black PE, rather than the less durable PVC on
other wires. If you use these wires you MUST prevent water ingress at
the ends, or using them across constant abrasion points.
If you have part of a pull up going through leaves, then use teflon
insulated #12 silvered copper available at times on eBay, but this
wire is not nearly as durable as the wireman stuff around bends or
under large horizontal stress. But it will keep the leaves and
branches from shorting you out. The silver/teflon wire is intended to
be laid in place and never again stressed, not really designed for
antennas. Using it for the vertical pull of an L keeps the stress
lengthwise and minimal, and does not subject it to bending. Also the
silvered strands maintain contact in the most current heavy part of
the antenna, and do not go bad with water ingress. You can solder the
fool out of the first inches, and you won't melt the teflon
insulation.
73, Guy
On Fri, Sep 28, 2012 at 12:06 PM, Jim F. <j_fitton@yahoo.com> wrote:
> 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
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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