A couple of things going on here. Loss to the ground from the FCP
increases as you go lower. Do it as high as you can and "get away
with it". That is something only you can figure out. Remember that
the unconnected end of the FCP wire has some considerable voltage on
it key down.
The fence wood is a significant dielectric, especially when wet, so
maximize the distance from the wood to the wire, and space the folds
in the FCP vertically if you are in front of the fence instead of on
top of it. Over the top of the fence, spacing the folds horizontally
will lose the least to the fence dielectric. All of that is subject
to what you can manage.
As to the bend, option 1) bend in the center, is not good. You
immediately loose some field cancellation in the middle, and increase
loss. 2) or 3) are about the same and should make little difference.
One person is using 40 feet straight in the middle and 13' at right
angles at either end. Another 34 feet in the middle and 16' at right
angles at either end. In either case there was no way to put 66 feet
in a line anywhere. Talking about really small lots there.
Flat white spray paint on bare #12 wire, spacers and supports in front
of white surfaces and mottled green/brown/gray/black on same in front
of trees and tree trunks have made FCP's and transformer boxes just
about invisible unless pointed out. Have seen some really impressive
stealth in some really upscale HOA environs :>)
Ultimately, as it has been with other correspondents, you get up what
you can get up. "Pure" and optimal doesn't mean anything if there's no
possibility to string it that way. It will still be way, way better
than short radials in the ground.
73 and Good Luck,
Guy.
On Sat, Aug 11, 2012 at 9:46 AM, Rick ve3mm <richardstasiak@gmail.com> wrote:
> Hello
>
> I am planning a 160 M FCP and inverted L installation for the upcoming
> winter season. The space available for both the inverted L and FCP are
> limited and I have to make the installation neat to please the XYL.
>
> I have a pressure treated board fence that can be used to support the FCP.
> The fence runs along the back side of my lot (60 feet) and down the two
> sides. I intend to manufacture pvc standoffs for the FCP that will be
> mounted on the fence approximately 5 feet above ground.
>
> As I see it, my FCP alternatives are as follows:
>
> 1) Mount the centre of FCP at a 90 degree intersection of two sides of the
> fence. Each side of the FCP will be straight, but they will be oriented at
> 90 degrees to each other.
>
> 2) The FCP mounted on the 60 foot length of fence on the back side of my
> lot with the last three feet of each side of the FCP wrapped on to the
> adjacent sides of the fence, 90 degree bends at each end.
>
> 3) The FCP mounted on the same 60 foot length of fence but offset so that
> one side of the FCP is in a straight plane and the end of the other is
> folded at 90 degrees for the last 6 feet.
>
> I would appreciate any comments from the group on which of these
> alternatives will offer the best FCP performance.
>
> Thanks and 73
>
> Rick ve3mm
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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