Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Old January 3rd 09, 02:31 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Mar 2007
Posts: 3,521
Default Does NEC-2 model wires as solid or hollow?

Dave wrote:
the only one who would care about that is art who believes that current
flows back down the inside of the conductor. for the rest of us an end of a
wire is an end of a wire... the difference in capacitance from a filled end
to a hollow tube, unless the diameter of the hollow tube is a good fraction
of a wavelength should be negligible.


Has anyone ever measured a difference between aluminum
tubing and a solid aluminum rod at the end of an antenna?
--
73, Cecil http://www.w5dxp.com
  #2   Report Post  
Old January 3rd 09, 02:49 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Jun 2008
Posts: 1,183
Default Does NEC-2 model wires as solid or hollow?

Cecil Moore wrote:
Dave wrote:
the only one who would care about that is art who believes that
current flows back down the inside of the conductor. for the rest of
us an end of a wire is an end of a wire... the difference in
capacitance from a filled end to a hollow tube, unless the diameter of
the hollow tube is a good fraction of a wavelength should be negligible.


Has anyone ever measured a difference between aluminum
tubing and a solid aluminum rod at the end of an antenna?


The rod is heavier.
  #3   Report Post  
Old January 3rd 09, 02:53 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Sep 2006
Posts: 33
Default Does NEC-2 model wires as solid or hollow?

On Jan 3, 9:49*am, Dave wrote:
Cecil Moore wrote:

Has anyone ever measured a difference between aluminum
tubing and a solid aluminum rod at the end of an antenna?


The rod is heavier.


Yes, yes, the rod is heavier. Very funny, but could someone answer
the original question.

-Dave, K3WQ
  #4   Report Post  
Old January 3rd 09, 03:33 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Jan 2008
Posts: 141
Default Does NEC-2 model wires as solid or hollow?


wrote in message
...
On Jan 3, 9:49 am, Dave wrote:
Cecil Moore wrote:

Has anyone ever measured a difference between aluminum
tubing and a solid aluminum rod at the end of an antenna?


The rod is heavier.


Yes, yes, the rod is heavier. Very funny, but could someone answer
the original question.

-Dave, K3WQ

The current is close to zero- why would it make any difference?
W4OP


  #5   Report Post  
Old January 3rd 09, 04:37 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Mar 2008
Posts: 1,339
Default Does NEC-2 model wires as solid or hollow?

On Jan 3, 9:33*am, "Dale Parfitt" wrote:
wrote in message

...
On Jan 3, 9:49 am, Dave wrote:

Cecil Moore wrote:


Has anyone ever measured a difference between aluminum
tubing and a solid aluminum rod at the end of an antenna?


The rod is heavier.


Yes, yes, the rod is heavier. *Very funny, but could someone answer
the original question.

-Dave, K3WQ

The current is close to zero- why would it make any difference?
W4OP


Wrong.!
The primary current is still flowing at the center. Particles occupy
the surface of the inside
and with the inter rejection of like particles produce a hoop stress
between them which
cannot be broken by a eddy current field, if present Thus the
particles cannot be ejected even tho there
is the primary ,current flow in the center ofr the tube. Remember.
the presence of particles is cast in stone
via the extension of the Gaussian law of statics. The presumption that
the current is near zero
is false until proven otherwise.. There is absolutely NO evidence that
reflection occurs in any shape or form at the
material ends of a radiator and all that pertains to such. PERIOD
Art Unwin KB9MZ.........xg


  #6   Report Post  
Old January 3rd 09, 05:00 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Jul 2006
Posts: 797
Default Does NEC-2 model wires as solid or hollow?


"Art Unwin" wrote in message
...

Wrong.!


I told you so!

The primary current is still flowing at the center. Particles occupy
the surface of the inside
and with the inter rejection of like particles produce a hoop stress


'hoop stress' now there's a good term for particle interaction!

between them which
cannot be broken by a eddy current field, if present Thus the
particles cannot be ejected even tho there
is the primary ,current flow in the center ofr the tube. Remember.
the presence of particles is cast in stone


the stone in this case is art's brain.

via the extension of the Gaussian law of statics. The presumption that
the current is near zero
is false until proven otherwise.. There is absolutely NO evidence that
reflection occurs in any shape or form at the
material ends of a radiator and all that pertains to such. PERIOD


nah, just because i can measure it with my simple tdr here doesn't mean it
happens... its all the magical mystery levitating neutrinos that cause all
the fun.



  #7   Report Post  
Old January 3rd 09, 05:30 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Mar 2008
Posts: 1,339
Default Does NEC-2 model wires as solid or hollow?

On Jan 3, 11:00*am, "Dave" wrote:
"Art Unwin" wrote in message

...

Wrong.!


I told you so!

The primary current is still flowing at the center. Particles occupy
the surface of the inside
and with the inter rejection of like particles produce a hoop stress


'hoop stress' *now there's a good term for particle interaction!

between them which
cannot be broken by a *eddy current field, if present *Thus the
particles cannot be ejected even tho there
is the primary ,current flow in the center ofr the tube. Remember.
the presence of particles is cast in stone


the stone in this case is art's brain.

via the extension of the Gaussian law of statics. The presumption that
the current is near zero
is false until proven otherwise.. There is absolutely NO evidence that
reflection occurs in any shape or form at the
material ends of a radiator and all that pertains to such. * *PERIOD


nah, just because i can measure it with my simple tdr here doesn't mean it
happens... its all the magical mystery levitating neutrinos that cause all
the fun.


David
You should know better.
Years ago I pointed out that the extension of the Gaussian law of
static results in Maxwells laws
with extension via mathematics. Before then I am sure that you were
aware of magnostatic fields
so it should not come as a surprize that the mathemetics is well
proven. When the mathematics were presented
before your very eyes you came up with reasons that defy the
imagination and totally absurd
You have the "field and waves" book by Ramo and Co so read it from end
to end with a smidgeon of understanding
so you may follow it from first principles. All the answers you seek
are
written in that book and they agree perfectly with mine. Nowhere does
it confirm what you state that Statics have zero connection
with magnetics which thus prevents mathematical connections. As for
hoop stress that is another derivitation of Newtons laws of action and
reaction and Newtons laws apply to the Universe including
electromagnetics via the Standard Model which, by the way ,includes
the Weak force that you also deny the presence of as well as the
chemical critera.
Your engineering ability is forcing your personal credability into the
ground.
Art
  #8   Report Post  
Old January 7th 09, 03:34 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Jun 2006
Posts: 440
Default Does NEC-2 model wires as solid or hollow?

On Jan 3, 10:37*am, Art Unwin wrote:
There is absolutely NO evidence that
reflection occurs in any shape or form at the
material ends of a radiator and all that pertains
to such. * *PERIOD.

____________

Art, the link below leads to empirical proof that such reflections
exist.

H. Gihring and G. Brown of RCA measured the relative current
distribution parallel to the axis of monopole radiators of several
lengths and widths, using an r-f current probe driving a thermal
meter.

The current distribution measured for the three radiator lengths
plotted all show the presence of reflections from the top of the
vertical wire, and in all three cases, current falls to zero at the
end of the radiator.

These are all fractional wavelength radiators not meeting your
definition of an antenna in "equilibrium."

This demonstrates that r-f current does not travel on the outside of a
wire on the way to the open end, and return from the open end along a
non-radiating path down the center of that conductor, as you believe.

http://i62.photobucket.com/albums/h8...reAntennas.gif

RF
  #9   Report Post  
Old January 7th 09, 10:21 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Jul 2006
Posts: 797
Default Does NEC-2 model wires as solid or hollow?


"Richard Fry" wrote in message
...
On Jan 3, 10:37 am, Art Unwin wrote:
There is absolutely NO evidence that
reflection occurs in any shape or form at the
material ends of a radiator and all that pertains
to such. PERIOD.

Art, the link below leads to empirical proof that such reflections
exist.


don't confuse him with facts, especially facts out of books... they are all
out of date since they don't have his latest theories included in them.


  #10   Report Post  
Old January 3rd 09, 04:42 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Aug 2006
Posts: 34
Default Does NEC-2 model wires as solid or hollow?

On Sat, 03 Jan 2009 08:31:30 -0600, Cecil Moore
wrote:

Has anyone ever measured a difference between aluminum
tubing and a solid aluminum rod at the end of an antenna?


Maybe Horace Lamb or Oliver Heaviside? Skin effect is dependent on
frequency as well as the material, right? Is the thickness of the
aluminum tubing significant at the frequency where you plan to use it?

I missed the beginning of the thread, so what is the original question
pertaining to?

In any case, I believe the rod would be heavier. ; )

S.T.W.


Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Building a Solid Copper Ground Pipe {Tube} with an Solid Iron Core. - Also - Water Drilling a Solid Copper Pipe for a Ground Rod. RHF Shortwave 12 January 17th 06 07:39 PM
Building a Solid Copper Ground Pipe {Tube} with an Solid IronC... [email protected] Shortwave 0 January 16th 06 10:04 PM
Building a Solid Copper Ground Pipe {Tube} with an Solid IronC... [email protected] Shortwave 0 January 16th 06 09:57 PM
Hollow State Newsletter is now online Les Shortwave 2 August 25th 05 03:36 PM
Hollow state news Beerbarrel Boatanchors 0 August 23rd 05 09:39 PM


All times are GMT +1. The time now is 04:47 PM.

Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017