Topband: 160m vertical with "top loading"

Lup Schlueter dj7sw at
Thu Apr 21 04:48:57 PDT 2011


i guess you are talking about a spider pole not a beam?
Look what is done in your country with poles:

If the hat wires are to long, you end up with a kind of windom with 
"glassfever feedsystem.
Best you modell it....before errecting.;-)

55/Lup DJ7SW

Am 20.04.2011 17:11, schrieb Stein Roar Brobakken:
> Hi
> We are going to install a 18m spiderbeam @ LA9TJA for use for 160m
> We been studying different top loading configurations, but we can't have the
> wires stringed from the top because it will break the spiderbeam ;)
> So our plan was to take this 18m and have it high in a tree.. maybe have
> totally 24 m or more vertical part feed via a loading coil or similar
> network in the bottom 2 m above ground.
> 2nd plan was to have 2-3 wires out of the spiderbeam on level from 6 to 10 m
> from bottom of the spiderbeam..
> There is then left about 12m to 8m of the vertical wire from this loading
> wires VS the vertical remaining part of vertical wire..
> After I my readings about vertical top loading the loading wires cannot be
> longer then the vertical part ?
> In my opion is that the loading wires can't be placed too far down to the
> vertical element, as I remember they have to be high as possible to "act" as
> capacitive loading on the element...
> Some guy wrote that the loading wires can be 1/8 wl maximum from the "end "
> of the vertical element... but since we  use this spiderbeam and it is not a
> fully 1/4 wavelength on 160m...
> Is it ok that we are mouting the loading wires 8m from the end of the
> vertical part ( 10m from bottom of the spiderbeam) and 2-3 x 11 meter of
> loading wires ? or should this loading wires be 7 m.. so they aren't longer
> than the remaining vertical element ?
> I think we should shorten them so they are shorter then vertical element and
> maybe have 3-4 of them... so we can have max vertical radiation..
> 73 LA6FJA Rag
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> UR RST IS ... ... ..9 QSB QSB - hw? BK

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