4nec2 wrote:

It's a pitty I was not aware of EZnec first few months after I
stumbled over the Nec2 program.

No it's not a pity, Arie.. Because then you might not have been inspired
to write 4nec2, which is what I use, rather than EZNEC. (Not that EZNEC
is better or worse, just different, and I've grown to like 4nec2)

Jim

Thanks for the kind words, something too seldom seen here lately.

Long ago, I told Art that I and some others wouldn't pay much attention
to his conjectures unless he posted some quantitative results showing
how his antenna creations were better than any others. He interpreted
this as an attack, and that slowly turned to the hatred you now see. He
dislikes EZNEC, I believe, simply because it's my program. I've
eventually become the personification of the cartel which is out to
belittle and deride him, preventing him from achieving the recognition
he believes he deserves for his revolutionary insights. I'm in no way a
qualified psychologist, but I see a number of similarities between this
and the behavior shown some time ago by Nathan "Chip" Cohen
(Fractenna"), who also considers me to be evil incarnate for much the
same reason. As far as I know, these are the only two people in the
entire world who dislike me this much. I'm afraid that by saying
complimentary things about me, you -- and by association, your program
-- will be joining me on Art's hate list.

I'm sorry to see that some of my postings and comments about EZNEC are
regarded by anyone as advertising, since I don't believe that
advertising is appropriate here. I do naturally use EZNEC as an example
or suggestion when giving an example of how to model something or to
illustrate a point and frequently recommend the free demo, but I don't
believe I've ever suggested that anyone buy EZNEC or that it's
necessarily superior to any other program. In fact, I often give tips on
using NEC-2. I also post corrections when someone says something about
EZNEC's capabilities which isn't true, and to answer questions about it.
I invite anyone who considers what I say about EZNEC to be out of line
to comment -- I'll certainly try to change my level of commentary if
there's general agreement that I've been advertising.

Roy Lewallen, W7EL

4nec2 wrote:
Just out of curiosity, but can anybody inform me what's the problem
between Art and Roy. In every posting of Art, Roy's name (or EZnec)
shows up. Why not mention NecWin+ or Supernec or others ?

I don't know Roy, but when reading his postings I sure think he is a
nice guy. When supplying answers on questions posted in this group,
it's expectable he does some EZnec advertising, because it's a
commercial product. Mostly he also takes the time to tell that there
are other productys around with similar capabilities...

It's a pitty I was not aware of EZnec first few months after I
stumbled over the Nec2 program.

:-(

Arie.

On 9 Mar, 13:06, Roy Lewallen wrote:
Thanks for the kind words, something too seldom seen here lately.

Long ago, I told Art that I and some others wouldn't pay much attention
to his conjectures unless he posted some quantitative results showing
how his antenna creations were better than any others. He interpreted
this as an attack, and that slowly turned to the hatred you now see. He
dislikes EZNEC, I believe, simply because it's my program. I've
eventually become the personification of the cartel which is out to
belittle and deride him, preventing him from achieving the recognition
he believes he deserves for his revolutionary insights. I'm in no way a
qualified psychologist, but I see a number of similarities between this
and the behavior shown some time ago by Nathan "Chip" Cohen
(Fractenna"), who also considers me to be evil incarnate for much the
same reason. As far as I know, these are the only two people in the
entire world who dislike me this much. I'm afraid that by saying
complimentary things about me, you -- and by association, your program
-- will be joining me on Art's hate list.

I'm sorry to see that some of my postings and comments about EZNEC are
regarded by anyone as advertising, since I don't believe that
advertising is appropriate here. I do naturally use EZNEC as an example
or suggestion when giving an example of how to model something or to
illustrate a point and frequently recommend the free demo, but I don't
believe I've ever suggested that anyone buy EZNEC or that it's
necessarily superior to any other program. In fact, I often give tips on
using NEC-2. I also post corrections when someone says something about
EZNEC's capabilities which isn't true, and to answer questions about it.
I invite anyone who considers what I say about EZNEC to be out of line
to comment -- I'll certainly try to change my level of commentary if
there's general agreement that I've been advertising.

Roy Lewallen, W7EL



4nec2 wrote:
Just out of curiosity, but can anybody inform me what's the problem
between Art and Roy. In every posting of Art, Roy's name (or EZnec)
shows up. Why not mention NecWin+ or Supernec or others ?

I don't know Roy, but when reading his postings I sure think he is a
nice guy. When supplying answers on questions posted in this group,
it's expectable he does some EZnec advertising, because it's a
commercial product. Mostly he also takes the time to tell that there
are other productys around with similar capabilities...

It's a pitty I was not aware of EZnec first few months after I
stumbled over the Nec2 program.

:-(

Arie.- Hide quoted text -

- Show quoted text -

Roy, Be assured that I do not hate anybody. That sort of emotion
is of no use. What I do abhor is disrespect and arrogance even though
my actions seam to invite it and apparently I have little control over
because of my personal circumstance. However as the
perceived leader of this group what you may see as a mild rebuke
is instantly latched onto by Richard who with his cfontinuing carping
spreads his arrogance and disrespect to others and it becomes
infectious to where I have no option to return in kind.
True one person scolded him for what he was doing and I thank him
( There for the grace of God go I, was the theme)
I am an Englishman and we don't run away from a fight if one is to
start. But now a new person has arrived on the scene who has an
understanding of what I have failed to project, thus you have a
different person to approach other than I for a deeper understanding
to your satisfaction. Hopefully this will put all the mutual
disrespect and abuse behind us and allow us to enjoy a new day.
I ask all to have respect for this new person for having the courage
to come forward inspite of what appeared as a hostile audience. I too
hope to learn from what he has to say as we now push the past aside.
Let me assure you that this is a new day for amature antennas and if
you wish to pursue then get hiold of AO or AOP from Brian Beasely
possibly being sent via the net. It is the only form that I am
presently aware of that allows pursuit of this subject and it is very
reasonably priced if he decides to re release it. Perhaps Brian will
come up on this thread and give details of contact issues
Regards
Art Unwin XG

On 9 mrt, 22:06, Roy Lewallen wrote:

I'm sorry to see that some of my postings and comments about EZNEC are
regarded by anyone as advertising, since I don't believe that
advertising is appropriate here.

Oh no that's not what I had in mind to say. Maybe I wrote it a bit
clumsy
because english is not my mother language. Many excuses for the
misunderstanding. I think you do a great job answering most of the
antenna related questions in this group. Most answers also provide me
with new information and/or insights.

Concerning Art's antenne, I am afraid I got lost somehow. Did Art
deliver
me a model and/or AO results. I am not sure anymore, because I
consult
this newsgroup only once each few days.
Art could send me his *.ant model file and let lme know what (good and/
or
wrong) resutls he got with AO and I'll let him know if I got similar
results or not.

Arie.

On Fri, 09 Mar 2007 13:06:09 -0800, Roy Lewallen wrote:

Thanks for the kind words, something too seldom seen here lately.

Long ago, I told Art that I and some others wouldn't pay much attention
to his conjectures unless he posted some quantitative results showing
how his antenna creations were better than any others. He interpreted
this as an attack, and that slowly turned to the hatred you now see. He
dislikes EZNEC, I believe, simply because it's my program. I've
eventually become the personification of the cartel which is out to
belittle and deride him, preventing him from achieving the recognition
he believes he deserves for his revolutionary insights. I'm in no way a
qualified psychologist, but I see a number of similarities between this
and the behavior shown some time ago by Nathan "Chip" Cohen
(Fractenna"), who also considers me to be evil incarnate for much the
same reason. As far as I know, these are the only two people in the
entire world who dislike me this much. I'm afraid that by saying
complimentary things about me, you -- and by association, your program
-- will be joining me on Art's hate list.

I'm sorry to see that some of my postings and comments about EZNEC are
regarded by anyone as advertising, since I don't believe that
advertising is appropriate here. I do naturally use EZNEC as an example
or suggestion when giving an example of how to model something or to
illustrate a point and frequently recommend the free demo, but I don't
believe I've ever suggested that anyone buy EZNEC or that it's
necessarily superior to any other program. In fact, I often give tips on
using NEC-2. I also post corrections when someone says something about
EZNEC's capabilities which isn't true, and to answer questions about it.
I invite anyone who considers what I say about EZNEC to be out of line
to comment -- I'll certainly try to change my level of commentary if
there's general agreement that I've been advertising.

Roy Lewallen, W7EL

I'm dismayed at the attitude shown toward Roy on this newsgroup. I've had the
pleasure and privilege of knowing him personally for many years. At one time,
while visiting me in my home in Florida, he personally installed EZNEC on my
computer. After knowing him for this long time I find Roy to be one of the most
helpful, honest, respectful, and friendly persons I've ever known.

IMO, we're fortunate to have him participate on this NG, as he's been a prolific
tutor on the subject, and many have learned from his knowledgeable presentations
and answers to questions many have asked.

Here's cheers to Roy!

Walt, W2DU

Thnak you Roy for a great program and for being the gentleman you are. I
will not forget your kind words to me at Dayton and your resupplying me with
your program after I stupidly lost it in a compuer malfunction.

Roy is "the best" and only an idiot would attack him personally. Roy- don't
pay any attention to this garbage.
--
k4ia
Buck
Fredericksburg, VA


"Roy Lewallen" wrote in message
...
Thanks for the kind words, something too seldom seen here lately.

Long ago, I told Art that I and some others wouldn't pay much attention
to his conjectures unless he posted some quantitative results showing
how his antenna creations were better than any others. He interpreted
this as an attack, and that slowly turned to the hatred you now see. He
dislikes EZNEC, I believe, simply because it's my program. I've
eventually become the personification of the cartel which is out to
belittle and deride him, preventing him from achieving the recognition
he believes he deserves for his revolutionary insights. I'm in no way a
qualified psychologist, but I see a number of similarities between this
and the behavior shown some time ago by Nathan "Chip" Cohen
(Fractenna"), who also considers me to be evil incarnate for much the
same reason. As far as I know, these are the only two people in the
entire world who dislike me this much. I'm afraid that by saying
complimentary things about me, you -- and by association, your program
-- will be joining me on Art's hate list.

I'm sorry to see that some of my postings and comments about EZNEC are
regarded by anyone as advertising, since I don't believe that
advertising is appropriate here. I do naturally use EZNEC as an example
or suggestion when giving an example of how to model something or to
illustrate a point and frequently recommend the free demo, but I don't
believe I've ever suggested that anyone buy EZNEC or that it's
necessarily superior to any other program. In fact, I often give tips on
using NEC-2. I also post corrections when someone says something about
EZNEC's capabilities which isn't true, and to answer questions about it.
I invite anyone who considers what I say about EZNEC to be out of line
to comment -- I'll certainly try to change my level of commentary if
there's general agreement that I've been advertising.

Roy Lewallen, W7EL

4nec2 wrote:
Just out of curiosity, but can anybody inform me what's the problem
between Art and Roy. In every posting of Art, Roy's name (or EZnec) shows
up. Why not mention NecWin+ or Supernec or others ?

I don't know Roy, but when reading his postings I sure think he is a
nice guy. When supplying answers on questions posted in this group,
it's expectable he does some EZnec advertising, because it's a
commercial product. Mostly he also takes the time to tell that there
are other productys around with similar capabilities...

It's a pitty I was not aware of EZnec first few months after I stumbled
over the Nec2 program.

:-(

Arie.

Art wrote:
"These of course need to be avoided since they are based on the yagi
being unbeaatable."

The Yagi in many ways is the first choice antenna.

It doesn`t increase windloading with conductors which add little to the
gain. It doesn`t require more than one drivepoint.

Terman and Kraus liked it and document it.

In Arnold B. Bailey`s catalog of antennas in "TV and Other Receiving
Antennas", no better array of simple wires, driven or parasitic, is to
be found.

If Art can best the Yagi, he should post a comparison.

Best regards, Richard Harrison, KB5WZI

On 9 Mar, 07:52, (Richard Harrison) wrote:
Art wrote:

"These of course need to be avoided since they are based on the yagi
being unbeaatable."

The Yagi in many ways is the first choice antenna.

It doesn`t increase windloading with conductors which add little to the
gain. It doesn`t require more than one drivepoint.

Terman and Kraus liked it and document it.

In Arnold B. Bailey`s catalog of antennas in "TV and Other Receiving
Antennas", no better array of simple wires, driven or parasitic, is to
be found.

If Art can best the Yagi, he should post a comparison.

Best regards, Richard Harrison, KB5WZI

O.k. all the guys you refer to are dead. Let us go with the majoratory
and assume they were correct before the passage of time. Now NEC is
alive and well and it is still used. We have found that it produces
arrays that the majority state is impossible, What do we do now, thro
NEC out of the window? Do we correct the underpinnings of NEC? Do we
push it under the carpet? This is not Congress, science requires
action.
Art

art wrote:
The most basic of all programs for antennas come from Roy
They do nothing but number crunching like a calculator and
will give you an answer close to what other programs provide
but not the same. The program does NOT help the user in any
way other than give you an answer regarding the performance
of what you provide.

Which, is, of course, the "sine qua non" for a *modeling* program.. it
should take your model and tell you what the performance will be.

It does NOT give you any help as to where
you could benefit in any way. When you move beyond the most
basic of antenna programes you can obtain help fr4om the
programs in that you don't have to specify actual dimensions
which may be useles because you can alow those dimensions
to be variable to allow the computor to guide you in the right
direction
to meet your desires.

This is an "antenna designing" program. Many such programs will use one
or more "antenna modeling" programs as part of their operation,
although, it's not by any means universal.


The cost of these type programs are similar
to eznec but can go up as high as a couple of thousand dollars
tho most amateurs should be satisfied with the cheapest versions

"antenna design" is a fairly wide field, and people literally spend
their life becoming good at one small part of it. There's a lot of
judgement and skill in antenna design, particularly when it comes to
things like mechanical/electrical tradeoffs and manufacturability.
There are tools designed to address one niche or another (e.g. there's
programs that are designed to optimize electrical performance microstrip
patch arrays, there's programs that are designed to optimize Yagi-Udas,
etc.)

Invariably, such tools are (at least originally) designed to be used by
a person who will do the "higher level" trades (Do I use a rectangular
or circular array of patches? What mechanical tolerances can I hold in
manfuacturing? Can I hold a 5 meter by 4 meter array flat enough to
actually work at Ka-band?)

There is some work on integrating all of these, but it's still baby
steps (for instance, taking a Solidworks model and turning it into a
meshed grid for modeling, or trying to integrate electrical, optical,
and mechanical models for large dishes (e.g. IMOS))

Some programs are designed around the yagi only for simplification.

yes.. back before computers got cheap, people worked out clever
analytical models for certain classes of antennas.. arrays of parallel
straight thin elements would be one that's particularly amenable to such
analysis. No surprise that as computers came to be more common, such
models would be first ones to be implemented.
These ofcourse need to be avoided since they are based on the
yagi being unbeatable.

Not at all. it's that people had equations for Yagis (based on
empirical experience that Yagis worked and met at least some of the
requirements), and people tend to want to work with what is familiar.
If for no other reason than you can compare the output of the modeling
code (or the optimization code) with something you've actually built and
see if it matches (aka validation).

So if a choice has to be made then programs
with variable dimension abilities together with a sufficient large
number of pulses are by far superior toi any other computor program.

Well, sure.. if you're going to any sort of Finite Element analysis (of
which the method of moments methods are just one subset), more elements
is better. But there's issues and concerns there, too: computational
resources is one, roundoff and numerical precision is another. Start
looking at models with hundreds of thousands of very tiny pieces, and it
becomes quite the numerical analysis/computer science challenge to
effectively compute it. And there are people working on it. I'm aware
of several efforts to implement some MoM and FDTD codes on large (1000
processor) cluster computers. (say you want to simulate an entire ship,
airplane, or spacecraft)
None of these programs agree with each other because of built in
errors

Error is the wrong word here (although technically correct), because it
is perjorative and implies that there is a fundamental bug, which is
generally not the case. All modeling codes are inaccurate to some
degree, partly because of the limited fidelity of the model input
(surely you don't want to spend the time to put in the actual atomic
composition of the elements) and partly because of a deliberate tradeoff
between speed and uncertainty (most people would rather have an answer
in a few minutes accurate to 1% than an answer next week accurate to 0.01%)

As a side point some programs provide errors because the user
doesn't understand the thinking behind garbage in and garbage out
because there is no oversight with respect to programmers error.

This is true of any modeling code. Better codes DO some reasonableness
checks for nonphysical structures and such. But, just like using a
chainsaw to saw down trees more rapidly than using a handsaw, there's
some assumption that the user has some skill.

On 9 Mar, 09:50, Jim Lux wrote:
art wrote:
The most basic of all programs for antennas come from Roy
They do nothing but number crunching like a calculator and
will give you an answer close to what other programs provide
but not the same. The program does NOT help the user in any
way other than give you an answer regarding the performance
of what you provide.

Which, is, of course, the "sine qua non" for a *modeling* program.. it
should take your model and tell you what the performance will be.

It does NOT give you any help as to where

you could benefit in any way. When you move beyond the most
basic of antenna programes you can obtain help fr4om the
programs in that you don't have to specify actual dimensions
which may be useles because you can alow those dimensions
to be variable to allow the computor to guide you in the right
direction
to meet your desires.

This is an "antenna designing" program. Many such programs will use one
or more "antenna modeling" programs as part of their operation,
although, it's not by any means universal.

The cost of these type programs are similar

to eznec but can go up as high as a couple of thousand dollars
tho most amateurs should be satisfied with the cheapest versions

"antenna design" is a fairly wide field, and people literally spend
their life becoming good at one small part of it. There's a lot of
judgement and skill in antenna design, particularly when it comes to
things like mechanical/electrical tradeoffs and manufacturability.
There are tools designed to address one niche or another (e.g. there's
programs that are designed to optimize electrical performance microstrip
patch arrays, there's programs that are designed to optimize Yagi-Udas,
etc.)

Invariably, such tools are (at least originally) designed to be used by
a person who will do the "higher level" trades (Do I use a rectangular
or circular array of patches? What mechanical tolerances can I hold in
manfuacturing? Can I hold a 5 meter by 4 meter array flat enough to
actually work at Ka-band?)

There is some work on integrating all of these, but it's still baby
steps (for instance, taking a Solidworks model and turning it into a
meshed grid for modeling, or trying to integrate electrical, optical,
and mechanical models for large dishes (e.g. IMOS))

Some programs are designed around the yagi only for simplification.

yes.. back before computers got cheap, people worked out clever
analytical models for certain classes of antennas.. arrays of parallel
straight thin elements would be one that's particularly amenable to such
analysis. No surprise that as computers came to be more common, such
models would be first ones to be implemented.

These ofcourse need to be avoided since they are based on the
yagi being unbeatable.

Not at all. it's that people had equations for Yagis (based on
empirical experience that Yagis worked and met at least some of the
requirements), and people tend to want to work with what is familiar.
If for no other reason than you can compare the output of the modeling
code (or the optimization code) with something you've actually built and
see if it matches (aka validation).

So if a choice has to be made then programs

with variable dimension abilities together with a sufficient large
number of pulses are by far superior toi any other computor program.

Well, sure.. if you're going to any sort of Finite Element analysis (of
which the method of moments methods are just one subset), more elements
is better. But there's issues and concerns there, too: computational
resources is one, roundoff and numerical precision is another. Start
looking at models with hundreds of thousands of very tiny pieces, and it
becomes quite the numerical analysis/computer science challenge to
effectively compute it. And there are people working on it. I'm aware
of several efforts to implement some MoM and FDTD codes on large (1000
processor) cluster computers. (say you want to simulate an entire ship,
airplane, or spacecraft)

None of these programs agree with each other because of built in
errors

Error is the wrong word here (although technically correct), because it
is perjorative and implies that there is a fundamental bug, which is
generally not the case. All modeling codes are inaccurate to some
degree, partly because of the limited fidelity of the model input
(surely you don't want to spend the time to put in the actual atomic
composition of the elements) and partly because of a deliberate tradeoff
between speed and uncertainty (most people would rather have an answer
in a few minutes accurate to 1% than an answer next week accurate to 0.01%)

As a side point some programs provide errors because the user
doesn't understand the thinking behind garbage in and garbage out
because there is no oversight with respect to programmers error.

This is true of any modeling code. Better codes DO some reasonableness
checks for nonphysical structures and such. But, just like using a
chainsaw to saw down trees more rapidly than using a handsaw, there's
some assumption that the user has some skill.

So Jim to sum up all you have said can I say that the production of
gaussian arrays by following NEC parameters is O.K. or correct and we
should leave well alone. Or should we remove the causes of its
creation
since it apparently is agreed that it is impossible? Since you work
with space antennas can you say it is not worth looking into or will
that be the same answer that you give your superviser next year as to
why you did not look into it?
I assure you Jim that the further you get into this the more will be
divulged as to what we have misunderstood in the past.
For a man in your position it is imperitive that you avail yourself of
a gaussian array as I have stated. Examine it as to why the product is
resonant in situ and also elements individually and try to come up as
to why
something that some would suggest was a bug produced such a symetrical
product? One would also question why NEC4 corroberated the performance
of the array and why internal algorithms did not deny it in the face
of the superior yagi .In no way does the production of an array by a
computor program provide cover for any pre stated contention . You of
course have to do what you think is correct in your work but one thing
that really disapoints me is that tho I do not expect to get a
response from the South African company as to how or what their
program provides in these circumstances I am more than a little
dismayed that the owner of 4NEC2 is not cooperating. He asked what AO
provided but now refuses to provide what
his program provides, thus I have a sneaking suspicion that all he did
was convert AO and AOP from DOS to WINDOWS without checking content
such that the contended bug or supposed error has carried thru today
without review.
I suppose we can all raise the flag and say it wasn't my job and close
our eyes to the whole saga and let other countries pursue for them
selves and reap the rewards while America sleeps.
Art XG