Hi Tom,
Please note that I said that "unless the inductor is quite
lossy". The point being that shortening the sloper wire absent
the introduction of excessive loss in the loading element will
not much affect the gain, pattern, or efficiency of the system.
You are indeed correct that loss is loss. And any loss in the
loading inductor will certainly reduce the system efficiency.
But I think the loading inductor losses can be controlled well
enough by good design of the inductor. So that loss in this
element should not be a big factor in the overall efficiency of
the system. Certainly not enough to reject the idea of
shortening the sloper resonator by inductive loading at the
feedpoint.
To: <towertalk@contesting.com>
>Date: Fri, 16 Oct 1998 21:46:57 -0400
>From: "w8ji.tom" <w8ji.tom@MCIONE.com>
>
>Hi Eric,
>
>You wrote:
>
>> If the sloper is attached to the correct point on the tower,
>> very little radiation takes place from the sloper wire itself.
>> So inductive loading to shorten this wire is not particularly
>> detrimental to efficiency unless the inductor is quite lossy.
>> Bottom line is that this is not a bad thing to consider.
>
>I don't understand that statement Eric.
>
>The loading inductor is in series with one terminal of the
>coax. How can it not add loss?
I didn't say that it didn't add loss. I merely said (or meant to
convey) that if it didn't add excessive loss, the system
efficiency would not be severely compromised. And that the fact
that the sloper wire was shortened would not be the source of any
reduction in efficiency that resulted from the exercise.
>Loss in a loading component has nothing to do with radiation, it
>only has to do with current flow through that component, and
>Kirchoff's law sez current is the same for either terminal of
>the coax, unless the feedline is radiating.
Exactly.
73, Eric N7CL
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