[Antennas] Home Brew balanced line

[Esterson/Pinsky]

I've used something like this for years to make standoff insulators for an
electric fence surrounding one of my orchards. I can attest that it is very
sturdy if you size the holes properly for the conductors, and you have a
wide choice of diameters and wall thicknesses to choose from (at least over
here where they invented the stuff). Sometimes I just skip making holes and
cuts and just cut slits at each end of the section of tube --seems to stay
almost as well, I think because the pressure of the slit on the wire tends
to create a bit of a dent in the plastic which holds the wire in place. If
you really want strong, make the holes and make a single slit to them
instead of a v-cut - your wire won't come out of the spreader unless a tree
falls on the line.

I've wondered about the effect of the lampblack  (carbon) used in the
formulation of many of these plastics to give them UV resistance. Anybody
know whether this is an issue at DC or at RF?
-Avi 4X6UA

At 19:44 17-12-02 -0600, Mike J Maloney wrote:
>Steve et al,
>May I suggest a more practical and probably cheaper material for the
>spreaders.   It is the black polyethylene 1/2" irrigation tubing sold in
>coils.   This stuff is quite tough, lightweight and impervious to
>sunlight and weather extremes.  The trick is to drill the parallel holes
>somewhat smaller than the diameter of the wires, then cut "V" shaped
>notches to the holes from each end.   The beauty of this is that the
>wires can be stretched out parallel for the desired length and the
>spreaders can then be pressed or "snapped" into place at the desired
>intervals.   You will find the spreader holds very tight to the wire and
>is very hard to slide once it is pressed into position.