Dear LF enthusiasts
and antenna experts,
I am planning to
re-engineer my antenna during the Spring, and I have a design decision to
make.
I use an "L"
antenna with a vertical section and a horizontal top section that is 20m
long. The "horizontal" top section is 10m high at the house end, and slopes
down to 5m at the far end. The vertical section is a single wire, with a large
loading coil/variometer at the bottom, in the usual time-honoured
fashion.
My choice is:- do I
feed the top section at the house end, in which case the vertical
section will be 10m high, or at the far end, where the vertical section
will be only 5m high? At first glance, it might be thought that the 10m vertical
would be preferable, but the fact that the top section slopes confuses the
situation.
Another problem
with feeding at the house end is that the vertical section is very near the
house and causes all sorts of RFI problems. It also picks up a load of
mains-borne rubbish!
Second question:-
Has anyone experienced any tangible benefits by including an extra loading
coil part-way up the vertical section?
All replies
gratefully received!
73, Dave G3WCB
IO91RM
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