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rickman · October 11th 14, 02:15 AM posted to rec.radio.amateur.antenna

On 10/10/2014 6:49 PM, wrote:
David Platt wrote:
* It is a wire dipole (keep the wire AWG to practical values, please).
* The dipole's length is variable.

I forgot to add to the second * item, that we could use .5 wavelengths,
.25 wavelengths, .1 wavelengths and .05 wavelengths for comparison purposes.

In many of the antenna discussions I've read, the term "dipole" is
often reserved for antennas which are of approximately half-wavelength
resonance at the frequency in question.

That is the amateur radio convention, but not so for a physicist.

When a physicist is talking about 1/2 wave dipoles it is either stated
explicitly or obvious from the context.

"Doublet" is used for a center-fed dipole-like antenna of other
lengths... for example, a 40-meter dipole which is actually being used
on 15 meters would be referred to as a doublet. In this sort of
terminology, one could consider a "dipole" to be a particular special
case of a "doublet".

Again, this is amateur radio convention. I don't think I have ever seen
the term doublet in a "science" publication.

Isn't this a amateur radio group? I did a google search and while
dipole comes up a lot more often that simply indicates they are more
often used.

When I did a search for definitions of doublet I found only a few that
refer to a short dipole as a doublet, mostly it is a synonym for dipole.

Of course, there's the other school of thought which calls *all* of
these antennas "dipoles" (e.g. a "short dipole" or a "5/4-wave
center-fed dipole".

Yep, like you find in physics books, which BTW will always be center
fed unless otherwise specified.

All this language stuff becomes important if you concider the reading
audience can consist of anyone from someone with a passing interest
and little education to a Sheldon Cooper theoretical physicist.

One term I have seen used often is Hertzian dipole for an electrically
short dipole.

--

Rick