Dipole with inherent directional capabilities?
 

Art,

I want to know about this concept. Can you tell me how to build one?
By what means might it change the very simple calculation of efficiency
given in the long and rambling thread which I am trying to avoid.

Take an antenna, any antenna you can dream up, measure the power
radiated in each direction. Add it all up. Compare that to the power
fed to the antenna.

A 100% efficient antenna radiates all the power it's fed.

A 50% efficent antenna radiates half the power it's fed.

A 150% efficent antenna radiates half again as much power as it's fed.

Why is an inherently directional "dipole" different from a yagi in this
respect?

Dan

Dipole with inherent directional capabilities?
 

Dipole with inherent directional capabilities?
 

John Smith wrote:
wrote:
Art,
...
JS

Oh yeah. That ~98% figure, that took for granted the antenna conductors
were chilled at or very near superconducting temps. or, the conductors
were constructed of a "yet to be developed" superconducting material.
But, certainly, you picked up that, that was implied from my previous text.

In fact, the skin effect is a phenomenon which could consume a whole
book to itself. I mean, why rf chooses to only travel the surface of
metal conductors? (why would the surface of metal offer less resistance
than the atoms of the metal inner most? Indeed, if you make the inner
material of silver and the other covering of a conductor of iron, it
still attempts to favor the iron!) Almost leading one to believe it
(rf) is attempting to "leap to the superconducting ether", but then, I
dream a lot ...

Regards,
JS

Dipole with inherent directional capabilities?
 

John,

Obviously you can have neither a 100% efficent antenna nor a 150%
efficient antenna. That doesn't change the definition of efficiency.
That was my point. It doesn't matter if you're talking about possible
or impossible antennas, efficiency is power out divided by power in.

Also, yes, a dipole has directional characteristics, but it would seem
that Art is talking about something more directional than a dipole that
is not a multielement array, and he asks us to imagine a dipole with
inherent directional capabilities

This suggests that it doesn't have the familar dipole directionality,
but something else.

What is that something else? How does it bear upon efficiency?

Dan

Dipole with inherent directional capabilities?
 

Dipole with inherent directional capabilities?
 

If I had seen this thread I wouldn't have wasted the time I spent just
making a post on 'efficiency.'..
Look guys... Antennas are not magic wands... They are well understood
EM entities, mathematically described by Maxwell and others in
equations, and subject to the laws of physics... When you guys get
tired of discussing the dark side of the force, check back in...


denny / k8do

Dipole with inherent directional capabilities?
 

"Look guys... Antennas are not magic wands"

Denny, I know that. I was hoping to do a little devil's advocate thing
here but newsgroups aren't the place for subtlety. Useful, anyway...
I'd rather have threads with antenna nonsense than threads with the
other nonsense that's been overwhelming this NG.

Should have put it in the other thread, sorry.

Dan

Dipole with inherent directional capabilities?
 

wrote:
I was hoping to do a little devil's advocate thing
here but newsgroups aren't the place for subtlety.

You forgot to add the smiley face. :-)
--
73, Cecil http://www.w5dxp.com

Dipole with inherent directional capabilities?
 

John, that glass aproach I hadn't thought of that in that the "skin
effect" exists
in only one direction and phase ,neat. Has any work been done on that
Art
John Smith wrote:
wrote:
Art,

I want to know about this concept. Can you tell me how to build one?
By what means might it change the very simple calculation of efficiency
given in the long and rambling thread which I am trying to avoid.

Take an antenna, any antenna you can dream up, measure the power
radiated in each direction. Add it all up. Compare that to the power
fed to the antenna.

A 100% efficient antenna radiates all the power it's fed.

A 50% efficent antenna radiates half the power it's fed.

A 150% efficent antenna radiates half again as much power as it's fed.

Why is an inherently directional "dipole" different from a yagi in this
respect?

Dan


Dan:

I am not Art. However, the questions look so ridiculous, let me provide
some possible answers.

A 100% efficient antenna radiates all the power it's fed.
ANSWER: Impossible. Well, outside of a superconducting physics lab anyway
!

A 150% efficent antenna radiates half again as much power as it's fed.
ANSWER: Again, impossible at this time, maybe in the future? Perhaps
aliens know how to do that?

Why is an inherently directional "dipole" different from a yagi in
this respect?
ANSWER: A dipole has "inherently directional properties", perhaps given
it by its creator? God? The laws of physics? Aliens? Well, it just
has them! And, you ask, why are they different than a yagi's? Geezh,
does a darn dipole even look like a darn yagi? I mean, come on, give me
some room here! Ok, let me give you a clue, there is more metal and
dielectric material in the yagi, that is why! grin

I think the top, very top efficiency of a silver plated-glass insulated
antenna in earths atmosphere, and with ample surface area to less "skin
effect" (probably space too, but there is
moisture/oxygen/nitrogen/carbon dioxide/etc. factor to atmosphere) is
~98%. When we finally understand the ether's relationship to an
antenna, it would NOT surprise me if we can bring that close to
99.99999999999999, not a great improvement--but hey, it gives me
something to think about.

Regards,
JS