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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