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-   -   ART vs. W8JI (https://www.radiobanter.com/antenna/146383-art-vs-w8ji.html)

Dale Parfitt[_3_] September 2nd 09 08:01 PM

ART vs. W8JI
 
Arrt,
I have repeatedly asked you to supply us with your original quote from
W8JI's page concerning a straight radiator is the best. Will you please do
so?
Now, there's an entire thread on this and no where any foundation.
Dale W4OP



Art Unwin September 2nd 09 08:49 PM

ART vs. W8JI
 
On Sep 2, 2:01*pm, "Dale Parfitt" wrote:
Arrt,
I have repeatedly asked you to supply us with your original quote from
W8JI's page concerning a straight radiator is the best. Will you please do
so?
Now, there's an entire thread on this and no where any foundation.
Dale W4OP

And no real discussion here either! You did not contribute

Dale, you can cry and cry and moan as much as you want. I will not let
you bully me and I am not at your beck and call.
If you have a comment with respect to the advantages of a radiater
being straight or not then go ahead and speak .If you feel hurt send
an E mail to Tom. Failing that go to QRZ yourself where I told you to
go.
Sooner or later you will have to get up from your couch

'Doc September 3rd 09 12:24 AM

ART vs. W8JI
 
Dale,
You should know better than that. Asking Art to prove something? You
gotta be kidding.
- 'Doc

Art Unwin September 3rd 09 12:54 AM

ART vs. W8JI
 
On Sep 2, 6:24*pm, "'Doc" wrote:
Dale,
You should know better than that. *Asking Art to prove something? *You
gotta be kidding.
*- 'Doc


And why not? This is a discussion group. Any one can concur or
challenge
the statement. If I supply the proof of anything then silly attacks
begin
I can handle them but it does not improve on my knoweledge.
I will state right now that overall size or straightness of a radiator
is not
implied in Maxwell's laws in any way. So I would like to know where
that notion came from.
Is that so bad?
So Doctor, what have you got to offer regarding radiator straightness
as a person skilled in the art ?

JIMMIE September 3rd 09 01:29 AM

ART vs. W8JI
 
On Sep 2, 7:54*pm, Art Unwin wrote:
On Sep 2, 6:24*pm, "'Doc" wrote:

Dale,
You should know better than that. *Asking Art to prove something? *You
gotta be kidding.
*- 'Doc


And why not? This is a discussion group. Any one can concur or
challenge
the statement. If I supply the proof of anything then silly attacks
begin
I can handle them but it does not improve on my knoweledge.
I will state right now that overall size or straightness of a radiator
is not
implied in Maxwell's laws in any way. So I would like to know where
that notion came from.
Is that so bad?
So Doctor, what have you got to offer regarding radiator straightness
as a person skilled in the art ?


Art, you already conceded to an exercise in futility that was a very
good example of a bent antenna in its worst case. You would think you
would have learned your lesson.

Jimmie

Cecil Moore[_2_] September 3rd 09 01:34 AM

ART vs. W8JI
 
Dale Parfitt wrote:
I have repeatedly asked you to supply us with your original quote from
W8JI's page concerning a straight radiator is the best.


Quoting W8JI's web page:
"How do we make a small antenna as efficient as possible?"
"... we make the antenna as large and straight as possible in a line.
We don't fold, bend, zigzag, or curve the antenna especially in the
high current areas."

I don't know what the fuss is all about. Transmission line
currents don't radiate (much) because they are out of phase.

Random folding of an antenna more often than not introduces
transmission line currents into the antenna itself - not
good for radiation purposes.

Transmission line currents cause destructive interference -
that's good for transferring power from one place to another
but not good for radiating RF.

There are certain special-case antennas where folding occurs
without introducing destructive interference, e.g. a 1/2WL
folded dipole or a full-wave quad where the wires are a
large enough percentage of a wavelength apart so they don't
cause near-field destructive interference.

Hint: RF radiation cannot be understood without understanding
constructive and destructive interference in the near, medium,
and far fields.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

tom September 3rd 09 01:41 AM

ART vs. W8JI
 
Cecil Moore wrote:
There are certain special-case antennas where folding occurs
without introducing destructive interference, e.g. a 1/2WL
folded dipole or a full-wave quad where the wires are a


Cecil, you should know by now that a half wave dipole of any type
couldn't be all that efficient or effective. Art says so.

tom
K0TAR

Dale Parfitt[_3_] September 3rd 09 01:42 AM

ART vs. W8JI
 

"Cecil Moore" wrote in message
...
Dale Parfitt wrote:
I have repeatedly asked you to supply us with your original quote from
W8JI's page concerning a straight radiator is the best.


Quoting W8JI's web page:
"How do we make a small antenna as efficient as possible?"
"... we make the antenna as large and straight as possible in a line.
We don't fold, bend, zigzag, or curve the antenna especially in the
high current areas."

I don't know what the fuss is all about. Transmission line
currents don't radiate (much) because they are out of phase.

Random folding of an antenna more often than not introduces
transmission line currents into the antenna itself - not
good for radiation purposes.

Transmission line currents cause destructive interference -
that's good for transferring power from one place to another
but not good for radiating RF.

There are certain special-case antennas where folding occurs
without introducing destructive interference, e.g. a 1/2WL
folded dipole or a full-wave quad where the wires are a
large enough percentage of a wavelength apart so they don't
cause near-field destructive interference.

Hint: RF radiation cannot be understood without understanding
constructive and destructive interference in the near, medium,
and far fields.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com


Thank you Cecil,
That's all I was looking for.

Dale W4OP



Art Unwin September 3rd 09 03:37 AM

ART vs. W8JI
 
On Sep 2, 7:34*pm, Cecil Moore wrote:
Dale Parfitt wrote:
I have repeatedly asked you to supply us with your original quote from
W8JI's page concerning a straight radiator is the best.


Quoting W8JI's web page:
"How do we make a small antenna as efficient as possible?"
"... we make the antenna as large and straight as possible in a line.
We don't fold, bend, zigzag, or curve the antenna especially in the
high current areas."

I don't know what the fuss is all about. Transmission line
currents don't radiate (much) because they are out of phase.

Random folding of an antenna more often than not introduces
transmission line currents into the antenna itself - not
good for radiation purposes.

Transmission line currents cause destructive interference -
that's good for transferring power from one place to another
but not good for radiating RF.

There are certain special-case antennas where folding occurs
without introducing destructive interference, e.g. a 1/2WL
folded dipole or a full-wave quad where the wires are a
large enough percentage of a wavelength apart so they don't
cause near-field destructive interference.


Cecil
It is not related to volume. It is because they are both closed
circuits thus all radiation
can be accounted for i.e. all the circuit wire contribute to
radiation. Any length less than 1WL does not !
If one introduces lumped loads then you have to cancel them, no
problem. Maxwell clearly stated that we are dealing with distributed
loads only, ie root L.C. The inclusion of volume is only because some
people cling to the magnetic field theory as opposed to the particle
theory. Equilibrium allows for multiple shapes and sizes for
achievement
Regards
Art


Hint: RF radiation cannot be understood without understanding
constructive and destructive interference in the near, medium,
and far fields.
--
73, Cecil, IEEE, OOTC, *http://www.w5dxp.com



Cecil Moore[_2_] September 3rd 09 12:19 PM

ART vs. W8JI
 
tom wrote:
Cecil, you should know by now that a half wave dipole of any type
couldn't be all that efficient or effective. Art says so.


Art might be quick to point out that there is one
wavelength of wire in a 1/2WL folded dipole. :-)
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com


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