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Old November 14th 03, 04:43 AM
Yuri Blanarovich
 
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Well, I care a great deal myself, I can't see how this would help me
at all. What would you do about it?


Mike,
to put in perspective, and I tried to point out in the course of threading this
thread, the significance is this:

1. Impact on effciency - efficiency is roughly proportional to the area under
the current curve over the radiator. When the current drop across the coil is
significant, that "eats" the portion of the curve and the curve above the coil
is much smaller (cosine or triangle shape), less efficiency (than shown in some
pictures).

2. Understanding the effect allows to better optimize the antenna performance,
be it through modeling or experimenting and measuring. That's why top hats look
so good. We are not talking just fraction of dB, on low bands that shows as 10s
of dBs on signal.

3. Proper modeling in software will allow better design and optimization. See
case of linear loaded 80m KLM beam vs. modified with loading coils, big
difference in pattern and gain and performance.

4. If the modeling software can not capture the effect, than your designs of
multielement loaded antennas are off.

This exercise already opened my eyes wider and after I test the designs, I will
hopefully come up with some better mobile antennas.

Yuri