John Smith I wrote:
Anyway, the word "pole" has always been confusing to me ... grin

Are you familiar with a plot of the poles and
zeros on a unit circle, e.g. filter response?
--
73, Cecil http://www.w5dxp.com

Richard Harrison wrote:
Cecil, W5DXP wrote:
"Seems the word "pole" requires an adjective to define the context for
antennas."

It should not hurt. My dictionary says a dipole antenna is a straight
conductor usually fed in the center.

However, dipole characteristics are determined by current distribution,
not the feeding if the feeder doesn`t radiate.

Seems to me, technically speaking, the two poles in
a "dipole" are electrical with opposite voltage polarities
at each end of the 1/2WL dipole. An electric monopole
has only one electrical pole, like a magnetic monopole
has only one magnetic pole.

A 1/2WL end-fed wire would then technically be a dipole
and the passive elements on a resonant Yagi would be
dipoles.
--
73, Cecil http://www.w5dxp.com

On Thu, 21 Jun 2007 21:14:58 GMT,
wrote:

In engineering there is good, fast and cheap. Pick any two.

That summary fails at every turn.

73's
Richard Clark, KB7QHC

Richard Harrison wrote:

SNIPPED


Seems to me, technically speaking, the two poles in
a "dipole" are electrical with opposite voltage polarities
at each end of the 1/2WL dipole. An electric monopole
has only one electrical pole, like a magnetic monopole
has only one magnetic pole.

A 1/2WL end-fed wire would then technically be a dipole
and the passive elements on a resonant Yagi would be
dipoles.

DIPOLE: If there is a polarity DIFFERENCE between the ends of a wire it
qualifies as a dipole [two poles ... two different charge levels ... two
different voltages ... etc.]

A RESONANT DIPOLE is a dipole with the voltages at the ends both equal in
magnitude and opposite in polarity.

Am I missing something?

On Thu, 21 Jun 2007 22:49:39 GMT,
wrote:

In engineering there is good, fast and cheap. Pick any two.

That summary fails at every turn.

Fails what?

Quality.

73's
Richard Clark, KB7QHC

Cecil Moore wrote:

...
Seems to me, technically speaking, the two poles in
...

In the following find, "# A monopole with a ground balance (mirror image).
www.novastars.com/antenna/antenna-glossary.htm"

However, this is far from what I expect to see when someone mentions
"dipole." The use of dipole to indicate a monopole with the mirrored
"pole" being created in the earth seems sparse in the material I have
digested--however, technically, you seem to have a argument in the use
you indicated ... however, I usually work with 1/2 wave monopoles
exclusively ... a small counterpoise allows me to divorce the antenna
from need of the ground (well, kinda ...)

I usually figure monopoles to be non-symmetrical, most-usually vertical,
unbalanced, and requiring a counterpoise ...

Dipoles I figure to be symmetrical balanced antennas ...

1) Monopole (wikipedia):
# A label used on some French wines to indicate sole ownership, or
monopoly, of the wine's name, with no bearing on the wine's quality.
www.valleyvineyards.com/wine_glossary_ijkl.htm

# A single self-supporting vertical pole with no guy wire anchors,
usually consisting of a galvanized or other unpainted metal or a wooden
pole with below grade foundations.
www.vapda.org/bylaw/gloss.htm

# A single exposed radiator, usually requiring a ground plane to provide
directivity (gain).
www.novastars.com/antenna/antenna-glossary.htm

# All known magnets have two poles, one south pole and one north pole.
The existence of a single such pole, termed a monopole, has not yet been
established but is believed by many physicists to exist on the basis of
theoretical studies. Lunar samples have been carefully searched on Earth
for the presence of monopoles.
history.nasa.gov/EP-95/glossary.htm

# The French term for a vineyard that is wholly owned by one estate. The
German word is "Alleinbesitz."
www.rieslingreport.com/glossary.html

# Used to denote a vineyard owned exclusively by one proprietor, the
word monopole appears on the label of a wine made from such a vineyard.
www.weinbauer.com/glossary/index.cfm

# A structure composed of a single spire used to support
telecommunications equipment.
http://www.co.jefferson.co.us/ext/dp...e-glossary.htm

# In physics, magnetic monopole is a term describing a hypothetical
particle that could be quickly clarified to a person familiar with
magnets but not electromagnetic theory as "a magnet with only one pole".
In more accurate terms, it would have net "magnetic charge". Interest in
the concept stems from particle theories like Grand Unified Theories and
superstring theories that predict either the existence or the
possibility of magnetic monopoles.
en.wikipedia.org/wiki/Monopole

2) Dipole (wikipedia):
# Speakers with drivers on opposite faces that are wired electrically
out of phase, creating an area of cancellation to the sides. Recommended
by THX for use as surround speakers, with null directed at the listener
to create a more ambient and non-localizable effect.
www.hometheatermag.com/glossary/

# Chemical compounds with an unequally distributed electric charge, such
as the water molecule: the oxygen atom is of negative charge and the two
hydrogen atoms are of positive charge. Dipolar molecules mutually
attract each other. This is how water molecules connect into clusters
via hydrogen bridges.
www.himalayasaltcrystal.com/glossary.htm

# A type of antenna with two defined opposing radiating elements, both
of the proper length for the frequency of operation, and each forming
the counterpoise for the other.
http://www.kareoke.com/glossary/micr...y_of_terms.htm

# A monopole with a ground balance (mirror image).
www.novastars.com/antenna/antenna-glossary.htm

# a compact source of magnetic force, with two magnetic poles. A bar
magnet, coil or current loop, if their size is small, create a dipole
field. The Earth's field, as a crude approximation, also resembles that
of a dipole.
www-spof.gsfc.nasa.gov/Education/wgloss.html

# (di·pole) (di¢p[omacr]l) 1. a molecule having charges of equal and
opposite signs but in which the center of the positive charge does not
coincide with that of the negative charge, a property which enables the
molecule to be bound electrostatically by both positively and negatively
charged groups. See polar compounds, under compound. 2. a pair of
electric charges or magnetic poles separated by a short distance.
http://www.mercksource.com/pp/us/cns...dmd_d_21zPzhtm

# a basic antenna element to which most other antennas are compared for gain
fwie.fw.vt.edu/tws-gis/glossary.htm

# 1. Without qualification usually means electric dipole, a system
composed of two charges of equal and opposite sign separated by a
distance. A magnetic dipole is an electric current loop enclosing a
finite area in a plane. See dipole moment. 2. Same as dipole antenna.
amsglossary.allenpress.com/glossary/browse

# A type of low-gain (2.2 dBi) antenna consisting of two (often
internal) elements.
www.wirelesstelcorp.com/glossary_of_terms.htm

# A molecule which has a definite separation between its center of
positive charge and center of negative charge. Such a molecule is said
to be polar. A polar species will be more attracted to a charged species
than will a non-polar one.
eies.njit.edu/~kebbekus/definitions-aquatic-chem%20htm.htm

# Magnetized object that possesses north and south magnetic poles. A bar
magnet and Earth are two examples.
http://www.physics.gmu.edu/~jevans/a...y/astrgl_d.htm

# An object whose centers of positive and negative charge do not
coincide. For example, a hydrogen chloride (HCl) molecule is an electric
dipole because bonding electrons are on average closer to the chlorine
atom than the hydrogen, producing a partial positive charge on the H end
and a partial negative charge on the Cl end.
http://www.madison.k12.wi.us/west/sc...vocabulary.htm

# Gentian Violet.
www.centurionndt.com/glossary.htm

# This is an antenna that is fed from the center (such as rabbit ears).
www.satellite-tv-hq.com/telecom-glossary-d.htm

# A speaker which radiates sound primarily in opposite directions, 180
degrees out of phase, This creates a null, or area with no sound, to the
sides of the speaker. Such designs are engineered by using drivers wired
out of phase, or by using both sides of a flat driver.
www.oregondv.com/Audio_FAQ_A-F.htm

# a pair of equal and opposite electric charges or magnetic poles
separated by a small distance
# an aerial half a wavelength long consisting of two rods connected to a
transmission line at the center
wordnet.princeton.edu/perl/webwn

Regards,
JS

Deek wrote:
A RESONANT DIPOLE is a dipole with the voltages at the ends both equal
in magnitude and opposite in polarity.

Am I missing something?

Any center-fed dipole, fed differentially and shorter
than 1/2WL, i.e. not resonant, has the voltages at the
ends both equal in magnitude and opposite in polarity.
--
73, Cecil http://www.w5dxp.com

Did you know that 6.02x10^23 angels dance on the head of a pin....

denny / k8do

On Thu, 21 Jun 2007 04:34:14 -0700, Denny wrote:

To further add
to the mix, I suggested he tie the tuner to the fence line and
backstop.

73's
Richard Clark, KB7QHC

That was canny advice, Richard... The top rail of the fence and
backstop 'could' have been an NVIS antenna - which will get you
smokin' reports out to a few hundred miles...
I do this routinely for Field Day with a horizontal loop for 80 meters
being strung about 20 feet high over a low, wet, fertilized field next
to a river... The guys run QRP off a battery and are amazed how they
can break pile ups... I have never bothered to point out to them that
the vast majority of their contacts are within a 500 mile circle...
They are happy and I believe in ignorance being bliss...


denny / k8do

a local qrp contact is still a qrp contact. Many contacts is better
than few, if that's what you are wanting to make.

It might not win field day, but it has to be better than not being
heard atall.

--
73 for now
Buck, N4PGW

www.lumpuckeroo.com

"Small - broadband - efficient: pick any two."