LAWRENCE MAYHEAD wrote:
Hi John,
I tried to model just such an antenna a few weeks ago using Eznec.The
idea was similar to yours to try to improve the top loading.However
the configuration showed NO improvement over having the 3 top wires in
paralel.Presumably at a spacing of only 2 feet they are far too close
together to have any effect.I am very intrested in any development of
this type and would be quite happy to model any ideas you may have.73s
Laurie.
I suggest trying a "second droopy wire" over the same span as each
existing top loading wire. The effective capacitance should go up
moderately (compared to replacing existing wire with larger diameter).
So in your example above, add wires a little below the three parallel
top wires, and join them at appropriate places. In practice, using the
same end terminations, a second wire could be made a little longer, so
would droop below the wire taking the tension. In practice a second
wire could tangle in the wind, but it does not tangle for computer
modelling :)
73, Bob ZL2CA
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