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Old April 29th 07, 04:00 PM posted to rec.radio.amateur.antenna
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Default Measuring Antenna Efficiency

On Sun, 29 Apr 2007 06:48:18 -0500, "Mike Lucas"
wrote:


"art" wrote:

I would say you are close enough to say you are correct. Because you
chose a dipole which is in a state of equilibrium and thus particles
projected from the dipole cannot collide with other particles from
other parasitic radiators. Aren't you not basically refering to the
foundations of Poyntings vector which like Gauss is refering to an
item in equilibrium when subjected to a time variable of zero value ?
If the item is not in a state of equilibrium collision
of particles may well occur without a radiation field reaction thus
one cannot calculate the resultant field since energy transfer due to
particle collision prevents the return of particles to the mother
radiator.

I've been reading Art's posts for some time now, mostly for the
entertainment value. Some of the recent posts were starting to make
sense, and this was causing me some concern: that my bafflegab
filter in the computor (sic) had gone out. Well, the above quote was
a wakeup call... I don't have a clue what he's saying. Can someone
translate, please.


Equi Librium is a drug, that is too big to swallow, so you have to
crush it into particles on one mother of a radiator. If you try to
swallow it whole, you will get one massive field reaction (a buzz) in
a time variable of zero value (like really fast) which may induce
projectile vomiting.

Maybe.

If not, then we will have to Gauss again.

73's
Richard Clark, KB7QHC
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Old April 29th 07, 04:18 PM posted to rec.radio.amateur.antenna
art art is offline
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Default Measuring Antenna Efficiency

On 29 Apr, 07:54, "Yuri Blanarovich" wrote:
"Mike Lucas" wrote in message

...







"art" wrote:


I would say you are close enough to say you are correct. Because you
chose a dipole which is in a state of equilibrium and thus particles
projected from the dipole cannot collide with other particles from
other parasitic radiators. Aren't you not basically refering to the
foundations of Poyntings vector which like Gauss is refering to an
item in equilibrium when subjected to a time variable of zero value ?
If the item is not in a state of equilibrium collision
of particles may well occur without a radiation field reaction thus
one cannot calculate the resultant field since energy transfer due to
particle collision prevents the return of particles to the mother
radiator.


I've been reading Art's posts for some time now, mostly for the
entertainment value. Some of the recent posts were starting to make
sense, and this was causing me some concern: that my bafflegab
filter in the computor (sic) had gone out. Well, the above quote was
a wakeup call... I don't have a clue what he's saying. Can someone
translate, please.


Mike W5CHR


Maybe if you put this in a word blender and spun long enough, maybe you
could get one sentence that would make some sense. :-)
I gave up way back when I could not understand what is the POLARITY in
antennas, which end up? So I guess humanity has to evolve for few more
centuries to catch up with "antenna wizard" and understand and appreciate
his piosneering work.
Judging by some other posts on other more earthly subjects, looks like there
are some missing gears in the gear box. What you expect from inventor that
has a patent on reflector beeing director and vice-voica. Looks like that
one will not ever be copyright violated. So take it with grain of salt and
enjoy the mumbo-jumbo-entoitenmeint. :-)

73 bada BUm- Hide quoted text -

- Show quoted text -


I don't know which patent you are refering to but I will examine your
particular statement.
Length alone is not an indication of reflective or atractive atributes
especially when viewed in combination of nearby elements. When
elements are in close association it is the cumulative effect that
determines whether it attracts or repels action from the driven
element and where the increased diametrical action of two intertwined
parasitic elements come to the fore. Knowing that english is not your
first language I must point out to you that the term reflector and
director are names applied to the function of a parasitic and not
necessarily a
physical description of length.
Art

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Old April 29th 07, 05:01 PM posted to rec.radio.amateur.antenna
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Default Measuring Antenna Efficiency


"Richard Clark" wrote in message
...
On Sun, 29 Apr 2007 06:48:18 -0500, "Mike Lucas"
wrote:


"art" wrote:

I would say you are close enough to say you are correct. Because you
chose a dipole which is in a state of equilibrium and thus particles
projected from the dipole cannot collide with other particles from
other parasitic radiators. Aren't you not basically refering to the
foundations of Poyntings vector which like Gauss is refering to an
item in equilibrium when subjected to a time variable of zero value ?
If the item is not in a state of equilibrium collision
of particles may well occur without a radiation field reaction thus
one cannot calculate the resultant field since energy transfer due to
particle collision prevents the return of particles to the mother
radiator.

I've been reading Art's posts for some time now, mostly for the
entertainment value. Some of the recent posts were starting to make
sense, and this was causing me some concern: that my bafflegab
filter in the computor (sic) had gone out. Well, the above quote was
a wakeup call... I don't have a clue what he's saying. Can someone
translate, please.


Equi Librium is a drug, that is too big to swallow, so you have to
crush it into particles on one mother of a radiator. If you try to
swallow it whole, you will get one massive field reaction (a buzz) in
a time variable of zero value (like really fast) which may induce
projectile vomiting.

Maybe.

If not, then we will have to Gauss again.

73's
Richard Clark, KB7QHC


Now I know what my daughter means when she talks about the random kids.


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Old April 29th 07, 06:30 PM posted to rec.radio.amateur.antenna
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Posts: 46
Default Measuring Antenna Efficiency

On Apr 28, 8:07 pm, art wrote:
On 5 Mar, 14:14, "Wayne" wrote:





Wayne wrote:
When the subject of antenna efficiency comes up, it often involves a
discussion of ground losses on verticals. What about, for example, a
dipole? Could one calculate "power out/power in" by measuring the VSWR
and declaring that everything not reflected was transmitted? It would
seem more accurate to actually measure power out and power in, but that
introduces inaccuracies by having to calibrate the setup. Thoughts?

"Roy Lewallen" wrote in message


...


There's no direct way to measure the total power being radiated other than
sampling the field at many points in all directions and integrating.
"Reflected" power is not power that isn't transmitted. You can find the
power being applied to the antenna by subtracting the "reverse" or
"reflected" power from the "forward" power, but that tells you nothing
about what fraction is radiated and what fraction lost as heat.


Roy Lewallen, W7EL


Thanks for the reply. My dipole example is intended to avoid transmission
line issues by not having one, and the elements are assumed to be reasonably
low loss. If I do some quick back-of-the-envelope calculations, for a VSWR
of 1.3:1, I get an efficiency of about 98.3% (using the equation
1-gamma^2). Assuming a resistance of 1 ohm in the dipole conductors the
efficiency I calculate is about 98.6% (72/73).


Are there any other loss issues missing in this example.


I would say you are close enough to say you are correct. Because you
chose a dipole which is in a state of equilibrium and thus particles
projected from the dipole cannot collide with other particles from
other parasitic radiators. Aren't you not basically refering to the
foundations of Poyntings vector which like Gauss is refering to an
item in equilibrium when subjected to a time variable of zero value ?
If the item is not in a state of equilibrium collision
of particles may well occur without a radiation field reaction thus
one cannot calculate the resultant field since energy transfer due to
particle collision prevents the return of particles to the mother
radiator.- Hide quoted text -

- Show quoted text -


what is a particle?

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