Mike
This probably explains why my antenna current was always less than
expected when using my 160 metre dipole, with feeders strapped, dangling
through tree branches! I'm in process of moving to a new QTH where I
hope to erect something approaching a quarter wave of wire, so will have
to pay attention to insulators.
73 to all
Tom, G3OLB
I commented that my antenna current had gone down following the
change from one top wire to three. I have re-engineered the far end
and have improved things. It seems that the far end insulation was
not as good as it could be (1m of plastic pipe). I have now restored
the current to what it was before the change by adding an extra
insulator in each leg.
This shows that it is just as important to keep the far end
=extremely= well insulated as it is to minimise losses at the high
current end.
The antenna still needs a little work to make it as mechanically stable
as possible, but it performs well. I have just had to put a small
attenuator in the front end of the receiver!
I look forward to some reports at the weekend.
Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm
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