Dipole in the trees
 

I've got plenty of trees to hang up a dipole for 40 meters and feed it with
ladder line. Power level = 100 Watts.
What's the opinion(s) on the wires contacting leaves, especially near the
end points? Better to use plastic insulated wire rather than enameled wire?

Better to hang the wire in the clear.

Otherwise, test lead wire is ususlly good to 15 KV.

73
H.


"Bob" wrote in message
...
I've got plenty of trees to hang up a dipole for 40 meters and feed it
with
ladder line. Power level = 100 Watts.
What's the opinion(s) on the wires contacting leaves, especially near the
end points? Better to use plastic insulated wire rather than enameled
wire?

On Sun, 24 Jul 2005 14:53:08 -0400, "Bob" wrote:

I've got plenty of trees to hang up a dipole for 40 meters and feed it with
ladder line. Power level = 100 Watts.
What's the opinion(s) on the wires contacting leaves, especially near the
end points? Better to use plastic insulated wire rather than enameled wire?


I use insulated wire. And a long-pole tree trimmer to keep the wires
in the clear. Not that hard to clear a path.

bob
k5qwg

Bob wrote:
I've got plenty of trees to hang up a dipole for 40 meters and feed it with
ladder line. Power level = 100 Watts.
What's the opinion(s) on the wires contacting leaves, especially near the
end points? Better to use plastic insulated wire rather than enameled wire?

I've had three HF dipoles strung thru four trees at my remote location
out in the boonies for five years. I use common Home Depot insulated
stranded #14 600V THHN wire. I've never had any problems at all at the
100-150W level with the wire including at the ends which are buried in
the foilage. I do tape the exposed solder joints at the insulators
though. There'a a lot of chatter here and there about trees being
quasi-conductors and catching fire etc. which I write it off as
mythology.

However I have had major problems with the support ropes. The rope is
the 3/16" jacketed UV-resistant Dacron type sold by The Wireman and
others for ~13 cents a foot, It's not Home Depot rope, it's supposedly
the best available for the purpose.

My experience indicates to me that while the wire is OK in all respects
thru trees the ropes have to be replaced every two years. The problem
is that tree branches of all sizes are very abrasive and will simply
eat thru rope if there's any relative motion between the rope and the
branches. Which is unaviodable in windy conditions. As a result I'm
seriously considering replacing the rope with the same wire I use for
the antennas.

w3rv

I have noted in the past that a KW will causes the leaves to turn brown, the
limb to die removing the offending tree limb via self amputation.

"Bob Miller" wrote in message
...
On Sun, 24 Jul 2005 14:53:08 -0400, "Bob" wrote:

I've got plenty of trees to hang up a dipole for 40 meters and feed it
with
ladder line. Power level = 100 Watts.
What's the opinion(s) on the wires contacting leaves, especially near the
end points? Better to use plastic insulated wire rather than enameled
wire?


I use insulated wire. And a long-pole tree trimmer to keep the wires
in the clear. Not that hard to clear a path.

bob
k5qwg

Ropes:== I tried using normal white nylon line (But Painting it black).
the paint makes it stronger and uv-resistant. And lasts longer.

"Brian Kelly" wrote in message
oups.com...
Bob wrote:
I've got plenty of trees to hang up a dipole for 40 meters and feed it
with
ladder line. Power level = 100 Watts.
What's the opinion(s) on the wires contacting leaves, especially near
the
end points? Better to use plastic insulated wire rather than enameled
wire?

I've had three HF dipoles strung thru four trees at my remote location
out in the boonies for five years. I use common Home Depot insulated
stranded #14 600V THHN wire. I've never had any problems at all at the
100-150W level with the wire including at the ends which are buried in
the foilage. I do tape the exposed solder joints at the insulators
though. There'a a lot of chatter here and there about trees being
quasi-conductors and catching fire etc. which I write it off as
mythology.

However I have had major problems with the support ropes. The rope is
the 3/16" jacketed UV-resistant Dacron type sold by The Wireman and
others for ~13 cents a foot, It's not Home Depot rope, it's supposedly
the best available for the purpose.

My experience indicates to me that while the wire is OK in all respects
thru trees the ropes have to be replaced every two years. The problem
is that tree branches of all sizes are very abrasive and will simply
eat thru rope if there's any relative motion between the rope and the
branches. Which is unaviodable in windy conditions. As a result I'm
seriously considering replacing the rope with the same wire I use for
the antennas.

w3rv

Hal Rosser wrote:
Ropes:== I tried using normal white nylon line (But Painting it black).
the paint makes it stronger and uv-resistant. And lasts longer.

I have around 500 feet of rope in use at the site and I am *not* gonna
paint 500 feet of rope!

Heh.

w3rv

On Sun, 24 Jul 2005 18:43:12 -0400, "Fred W4JLE"
wrote:

I have noted in the past that a KW will causes the leaves to turn brown, the
limb to die removing the offending tree limb via self amputation.

Ain't never run no 'gallon' ...

bob
k5qwg



"Bob Miller" wrote in message
.. .
On Sun, 24 Jul 2005 14:53:08 -0400, "Bob" wrote:

I've got plenty of trees to hang up a dipole for 40 meters and feed it
with
ladder line. Power level = 100 Watts.
What's the opinion(s) on the wires contacting leaves, especially near the
end points? Better to use plastic insulated wire rather than enameled
wire?


I use insulated wire. And a long-pole tree trimmer to keep the wires
in the clear. Not that hard to clear a path.

bob
k5qwg

It is a whole lot easier to buy black "550" (parachute) cord. Braided and
sheathed, it is great. Have had mine up for over 5 years in the open with no
problem. In areas where there was contact with something, i.e., a tower or
tree about 3 years is all I can get.

Sportsman's Guide usually has the stuff every couple of issues.

On Sun, 24 Jul 2005 20:50:46 -0400, "Hal Rosser"
wrote:

Ropes:== I tried using normal white nylon line (But Painting it black).
the paint makes it stronger and uv-resistant. And lasts longer.

Some different thoughts on painted rope:

Synthetic fibre ropes are subject to UV attack, but they are also
often subject to chemical attack.

If your rope really is nylon (Polyamide), it is resistant to alkalis
but is sensitive to acid attack. It should not be painted with
anything that will be acidic, or create acidic products in
decomposition.

In most serious rigging applications, any synthetic fibre rope or
sling that was subject to chemical inundation (acid, alkali, solvents,
paints, fuel, oil, contaminated water etc) would be condemned.
Additionally, painting the exterior of a rope probably increases the
risk of rot and mildew internal to the rope.

Over here, a very low cost synthetic fibre laid three stand rope
called "Silver Rope" (flat spin taniklon fibre), white in colour, is
used for marine applications. Not only is it dirt cheap, but it seems
to last on small boat moorings for years. I have had 6mm halyards of
Silver Rope up for over 5 years and there is no significant
degradation. (I wouldn't paint it, it resists mild acids, but is
attacked by alkalis.) (Silver Rope is about the same strength as
natural fibre rope, and about 50% of that of nylon.)

My choice for a synthetic fibre rope for non-structural antenna
rigging would be Silver Rope. It is cheap, it holds knots and splices
well, it is resistant to mild acids (pollution by products), and seems
to give a reasonable service life in UV exposure.

Polypropylene is also resistant to mild acids (and alkalis), but it is
a slippery (greasy) rope that doesn't hold knots or splices as readily
as natural fibre ropes.

Owen
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