Hi Everett,
Have you read k2av.com [Placing an FCP] ? And had a look at k2av.com [Loss
List] ?
An FCP’s most important aspect is avoiding loss factors. Going through
bushes or through tree branches puts very high magnetic fields right next
to wood, inducing dielectric loss in the wood. Insulation keeps it from
shorting, maybe, but only increases loss.
Use #12 bare wire and #11 standard wall Teflon tubing pushed over it if you
absolutely *must* route the FCP that way (decidedly *not* recommended).
Note that the voltages on the last fold, closest to the insulated end of
the FCP, get pretty high. See the section on 160-80 dual banding which
refers to the voltages on the FCP at QRO.
Note that the web page recommends a five foot radius tunnel (10 foot
diameter) free of vegetation and other dielectric materials around the FCP.
Uneven height above ground is not an issue. The *minimum* height above
ground along the FCP’s length is an issue. Keep the FCP in the plane at
right angles to the vertical wire, at the same altitude above sea level,
regardless of terrain.
Remember you are *fighting loss* which hamdom at large seems mostly unaware
of. Think of “death by a thousand paper cuts” as you work on loss. A bunch
of small avoidances can add up to a big one.
73, Guy K2AV
On Sat, Nov 18, 2017 at 10:02 AM Everett Sharp via Antennaware <
antennaware@contesting.com> wrote:
> Well Guys,
>
> Just joined the list and have been operating on 160 Meters now for about 2
> weeks. The antenna is Inverted L, which is 52’ vertical and 103’
> horizontal. Currently have 4, on the ground, 1/4 wave radials/with ground
> rod. The system works much better than expected. However, I plan on
> upgrading to a FCP and should have it up and running in a week, or so. My
> problem is I will have to run part of the FCP through some high bushes on
> one side. Also the ground drops off, by a lot, on one half of the planed
> counterpose.
>
> So my thinking is to use insulated wire, even though it is not
> recommended, because the FCP will have to make contact with the bushes on
> one 1/2 of it for a short distance (any thoughts?). The side where I will
> have to pass through the bushes is the side where the ground drops off and
> the far end will be 15’, or so above the ground. The other half will be 8’
> above the ground. So do I need to bend the one half of the FCP to maintain
> the same distance above the ground, or keep it level? Half of the FCP will
> be at 8’, or so with the middle at 8’ and the far end of the other side a
> 15’ AGL.
>
> Any help, or recommendation will be greatly appreciated. I have wound the
> 1:1 transformer on a T300-D2 core, so that part is done.
>
> Everett N4CY
>
> Sent from my iPad
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