On Fri, 24 Feb 2006 20:52:11 GMT, Cecil Moore wrote:


Semantics strikes again. To distinguish the left-most low resistance
point on an SWR circle from the right-most high resistance point, we
mid-20th-century Aggie EEs called the leftmost point, "resonant", and
called the rightmost point, "anti-resonant".

If you and I were ever to agree on definitions, I have no doubt
that we would also agree on concepts.

I am sure we are talking the meaning of the terms (semantics) rather
than the underlying concept.

Narrowing the term resonance to only apply to the resonance that
exhibits a series resonance equivalent behaviour seems to me to
unnecessarily limit the meaning of resonance (though I note it is used
in optics to some extent).

I think of the high impedance of a dipole with zero reactance at some
frequencies also as a resonance, and I think you did too when you said
recently to Amos "jX is only zero at resonance." If that is to mean
that jX is "only ever" zero at resonance, then if jX is zero, you have
resonance, whether R is high or low.

On that basis, one would have to say that a full wave centre fed
dipole exhibits (at the feed point) resonance similar to a lossy
parallel tuned circuit and should be considered a resonant radiator.

Owen
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