Dr. Gerald N. Johnson wrote:
As Jerry points out, there are some amongst us who believe that a tuner at
the antenna feed point tunes the antenna wire to resonance. It does not.
Why not? The tuner can supply the needed series capacitive reactance to
bring the feed impedance resistive. Isn't a resistive feed impedance (no
matter what the magnitude) the definition of resonance? And when that
antenna is resonant, isn't the current in the wire maximized? Isn't
there a possibility of greater circulating current than feedline
current, if the antenna Q is higher.
Jerry,
Mischievously ....... I just tried an interesting experiment. I took a
100 Ohm resistor in series with a 100pF capacitor and placed them across
the "antenna" terminals of my tuner. I watched them carefully as I
adjusted the tuner for a 50 Ohm match. At no time did I see any change
in the physical appearance of the resistor or capacitor, so I don't see
how the tuner was making them "resonant". I was disappointed - I'd hoped
from your description I might see them "morph" into a 50 Ohm resistor
before my very eyes :)
73,
Steve G3TXQ
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