Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Old October 28th 14, 10:33 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Sep 2012
Posts: 1,382
Default Segments of antennae

Any small part of an antenna radiates a little bit and also acts as a
transmission
line to feed power onto the next small bit which behaves similarly.

Therefore, it stands to reason that an antenna that is shorter than another
antenna radiates less than does that other antenna.

(Note that despite the abusive and infantile interjections from a certain
quarter, that I am not discussing feeding, nor am I discussing impedance
matching, and neither have I ever been discussing them. Also, I understand
very well the behaviour of transmission lines, complex conjugate matching,
and
radiation by accelerated charges. What I am musing on
is the behaviour of antennae once the power has been fed to it, and that
further
musing is motivated by that full underlying comprehension. I do not
understand
why that infantile quarter tries to accuse me of not understanding those
topics, when
I have never made them the focus of my discussion)

Remember that EZ-NEC does its analysis by dividing up antennae into small
segments
and calculates the antenna performance in certain directions by summing
together all
the individual contributions to the far field. That EZ-NEC works by
calculating a big
result from lots of little results is itself an indication that little bits
of antenna do not
radiate as well as do big bits, viz, short antennae do not radiate as well
as do big antennae.




  #2   Report Post  
Old October 29th 14, 12:33 AM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Jun 2006
Posts: 1,898
Default Segments of antennae

gareth wrote:
Any small part of an antenna radiates a little bit and also acts as a
transmission
line to feed power onto the next small bit which behaves similarly.


Nope.

Therefore, it stands to reason that an antenna that is shorter than another
antenna radiates less than does that other antenna.


Since your original premise is false, the conclusion is nonsense.

(Note that despite the abusive and infantile interjections from a certain
quarter, that I am not discussing feeding, nor am I discussing impedance
matching, and neither have I ever been discussing them. Also, I understand
very well the behaviour of transmission lines, complex conjugate matching,
and
radiation by accelerated charges. What I am musing on
is the behaviour of antennae once the power has been fed to it, and that
further
musing is motivated by that full underlying comprehension. I do not
understand
why that infantile quarter tries to accuse me of not understanding those
topics, when
I have never made them the focus of my discussion)


Because you make nonsense statements like the very first sentence of
this post then attempt to come to a conclusion based on that nonsense.

Remember that EZ-NEC does its analysis by dividing up antennae into small
segments
and calculates the antenna performance in certain directions by summing
together all
the individual contributions to the far field.


It is EZNEC, not EZNEC, and EZNEC is a wrapper around a NEC engine.

All implementations of NEC use the same method in the engine but not
all implementations of NEC are EZNEC.

EZNEC is a copywrited commercial product.

NEC calculates the various parameters of an antenna by breaking it into
small segments which are used to perform discrete numerical analysis
of the differential equations that describe all antennas.

It does this because digital computers can not solve continuous differential
equations directly and a specialized analog computer that could would be
too expensive to build these days.

That EZ-NEC works by
calculating a big
result from lots of little results is itself an indication that little bits
of antenna do not
radiate as well as do big bits, viz, short antennae do not radiate as well
as do big antennae.


As a NEC engine does not work as you describe, your premise is false,
your logic is puerile and your conclusion is nonsense.

And there is no such thing as EZ-NEC as you have been told several times
now, you babbling old fool.


--
Jim Pennino
  #3   Report Post  
Old October 29th 14, 07:47 AM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Oct 2014
Posts: 2
Default Segments of antennae

Wrote in message:
gareth wrote:
Any small part of an antenna radiates a little bit and also acts as a
transmission
line to feed power onto the next small bit which behaves similarly.


Nope.

Therefore, it stands to reason that an antenna that is shorter than another
antenna radiates less than does that other antenna.


Since your original premise is false, the conclusion is nonsense.

(Note that despite the abusive and infantile interjections from a certain
quarter, that I am not discussing feeding, nor am I discussing impedance
matching, and neither have I ever been discussing them. Also, I understand
very well the behaviour of transmission lines, complex conjugate matching,
and
radiation by accelerated charges. What I am musing on
is the behaviour of antennae once the power has been fed to it, and that
further
musing is motivated by that full underlying comprehension. I do not
understand
why that infantile quarter tries to accuse me of not understanding those
topics, when
I have never made them the focus of my discussion)


Because you make nonsense statements like the very first sentence of
this post then attempt to come to a conclusion based on that nonsense.

Remember that EZ-NEC does its analysis by dividing up antennae into small
segments
and calculates the antenna performance in certain directions by summing
together all
the individual contributions to the far field.


It is EZNEC, not EZNEC, and EZNEC is a wrapper around a NEC engine.

All implementations of NEC use the same method in the engine but not
all implementations of NEC are EZNEC.

EZNEC is a copywrited commercial product.

NEC calculates the various parameters of an antenna by breaking it into
small segments which are used to perform discrete numerical analysis
of the differential equations that describe all antennas.

It does this because digital computers can not solve continuous differential
equations directly and a specialized analog computer that could would be
too expensive to build these days.

That EZ-NEC works by
calculating a big
result from lots of little results is itself an indication that little bits
of antenna do not
radiate as well as do big bits, viz, short antennae do not radiate as well
as do big antennae.


As a NEC engine does not work as you describe, your premise is false,
your logic is puerile and your conclusion is nonsense.

And there is no such thing as EZ-NEC as you have been told several times
now, you babbling old fool.


--
Jim Pennino


Don't hold back Jim, tell him straight....
--
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
The inefficiency of short antennae compared to long antennae, as previously discussed. gareth Antenna 119 February 24th 15 09:54 AM
Antennae for 136kHz? gareth Antenna 8 June 18th 14 04:42 PM
Fractal antennae? Sparky[_3_] Equipment 10 February 17th 14 10:23 AM
Fractal antennae? Sparky[_3_] Shortwave 10 February 17th 14 10:23 AM
Homemade Antennae, help Steve Muir Antenna 6 April 12th 04 04:44 AM


All times are GMT +1. The time now is 03:00 AM.

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