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Old October 14th 04, 10:47 PM
Chuck
 
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Roy Lewallen wrote in message
...

...pirated copy of EZNEC.


That is an absolute lie!

My disk is an original - with a large, black,
bold, italicized EZNEC at the top of its
label - and the party from whom I acquired
it, gave it to me with your full knowledge
and approval. I can only assume this lie is
an egregious and deliberate attempt on
your part to defame. I will not discuss this
further in public.

I made Chuck an offer a while back, as follows: That if he has the
Raibeam tested at a certified antenna range and the results show a
free-space gain of at least 5.5 dBd (7.65 dBi) with simultaneous 25 dB
or greater f/b ratio, I'll pay the test fee. This is performance less
than he claims and less than he claims his model shows. But so far he
hasn't taken me up on the offer.



It's rather moot, now that I am no longer in
business. However, If it's your desire to
spend money to embarrass yourself, I
won't argue.

There were two reasons why I let your offer
slide. First, I was unaware of any testing
facilities in my area, and second, I was
struggling to meet customer demand and
could not justify spending the time to
develop a unit for UHF, since it was my
understanding that most testing facilities
could not accommodate frequencies lower
than 100 MHz or so.

I've since learned that the US Army testing
range at Fort Huachuca in Tucson, AZ is
open to civilian testing, and they can
accommodate frequencies as low as 50
MHz.

My wife will finish her chemotherapy and
radiation treatments in March, and since
she is quite ill, I cannot foresee my being
available until after that time.

Allowing say 30 days or so for me to
prepare an antenna, I invite you to make
the arrangements in Tucson - say April -
May, 2005 or so - and I will be more
than happy to join you there.

Is this agreeable?

Chuck, WA7RAI


  #2   Report Post  
Old October 14th 04, 11:33 PM
Roy Lewallen
 
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Chuck wrote:
Roy Lewallen wrote in message
...

...pirated copy of EZNEC.



That is an absolute lie!

My disk is an original - with a large, black,
bold, italicized EZNEC at the top of its
label - and the party from whom I acquired
it, gave it to me with your full knowledge
and approval. I can only assume this lie is
an egregious and deliberate attempt on
your part to defame. I will not discuss this
further in public.


I'll take your word for it, and apologize. You had claimed long ago that
the program was given or sold to you, but for reasons of your own you
would never tell me from whom. (Although I certainaly approve of such
transfers, I never gained knowledge of whom the transfer was from.) In
my posting of Sept. 26, 1997 on this newsgroup, I said:

I don't generally give support to someone who's not a registered user,
but in this case I guess it's necessary. (You still haven't sent me
the name of the person who gave you the program, so I can transfer the
ownership to you from him.)


Because you never furnished that information, I assumed that you had
acquired it illicitly.

If you'll email me the name or call of the person from which you
acquired it and the amount you paid, I'll promptly send you a full
refund, in accordance with my guarantee. You're obviously not a
satisfied user.



I made Chuck an offer a while back, as follows: That if he has the
Raibeam tested at a certified antenna range and the results show a
free-space gain of at least 5.5 dBd (7.65 dBi) with simultaneous 25 dB
or greater f/b ratio, I'll pay the test fee. This is performance less
than he claims and less than he claims his model shows. But so far he
hasn't taken me up on the offer.




It's rather moot, now that I am no longer in
business. However, If it's your desire to
spend money to embarrass yourself, I
won't argue.

There were two reasons why I let your offer
slide. First, I was unaware of any testing
facilities in my area, and second, I was
struggling to meet customer demand and
could not justify spending the time to
develop a unit for UHF, since it was my
understanding that most testing facilities
could not accommodate frequencies lower
than 100 MHz or so.

I've since learned that the US Army testing
range at Fort Huachuca in Tucson, AZ is
open to civilian testing, and they can
accommodate frequencies as low as 50
MHz.

My wife will finish her chemotherapy and
radiation treatments in March, and since
she is quite ill, I cannot foresee my being
available until after that time.

Allowing say 30 days or so for me to
prepare an antenna, I invite you to make
the arrangements in Tucson - say April -
May, 2005 or so - and I will be more
than happy to join you there.

Is this agreeable?


No, you'll have to make the arrangements.

Determine the cost of the test. I suggest that we find someone who is
willing and we both can trust to whom I'll send the money the test will
cost, as proof of my willingness and ability to pay the test fee if the
antenna meets the criteria. Let me know when the test is to be done, and
I'll come down and observe. The person who pays will have the legal
right to make the results public. I agree in advance to do so if I pay;
I expect you to do likewise.

Roy Lewallen, W7EL
  #3   Report Post  
Old October 15th 04, 01:13 AM
Wes Stewart
 
Posts: n/a
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On Thu, 14 Oct 2004 15:33:23 -0700, Roy Lewallen
wrote:

|Chuck wrote:
| Roy Lewallen wrote in message
| ...
|
|...pirated copy of EZNEC.
|
|
| That is an absolute lie!
|
| My disk is an original - with a large, black,
| bold, italicized EZNEC at the top of its
| label - and the party from whom I acquired
| it, gave it to me with your full knowledge
| and approval. I can only assume this lie is
| an egregious and deliberate attempt on
| your part to defame. I will not discuss this
| further in public.
|
|I'll take your word for it, and apologize. You had claimed long ago that
|the program was given or sold to you, but for reasons of your own you
|would never tell me from whom. (Although I certainaly approve of such
|transfers, I never gained knowledge of whom the transfer was from.) In
|my posting of Sept. 26, 1997 on this newsgroup, I said:
|
| I don't generally give support to someone who's not a registered user,
| but in this case I guess it's necessary. (You still haven't sent me
| the name of the person who gave you the program, so I can transfer the
| ownership to you from him.)
|
|Because you never furnished that information, I assumed that you had
|acquired it illicitly.
|
|If you'll email me the name or call of the person from which you
|acquired it and the amount you paid, I'll promptly send you a full
|refund, in accordance with my guarantee. You're obviously not a
|satisfied user.
|
|
|
| I made Chuck an offer a while back, as follows: That if he has the
| Raibeam tested at a certified antenna range and the results show a
| free-space gain of at least 5.5 dBd (7.65 dBi) with simultaneous 25 dB
| or greater f/b ratio, I'll pay the test fee. This is performance less
| than he claims and less than he claims his model shows. But so far he
| hasn't taken me up on the offer.
|
|
|
| It's rather moot, now that I am no longer in
| business. However, If it's your desire to
| spend money to embarrass yourself, I
| won't argue.
|
| There were two reasons why I let your offer
| slide. First, I was unaware of any testing
| facilities in my area, and second, I was
| struggling to meet customer demand and
| could not justify spending the time to
| develop a unit for UHF, since it was my
| understanding that most testing facilities
| could not accommodate frequencies lower
| than 100 MHz or so.
|
| I've since learned that the US Army testing
| range at Fort Huachuca in Tucson, AZ is
| open to civilian testing, and they can
| accommodate frequencies as low as 50
| MHz.

Fort Huachuca is not located in Tucson, it is located at Sierra Vista,
AZ, approximately 90 miles SE of Tucson.

Some of the capabilities are listed he

http://www.epg.army.mil/Test_Beds/ATF.htm

As an aside, I have tested under the ARC range and have been to the
top of the "Red Tower" just to look around. Quite a view! I've seen
photos of an M1-A1 tank mounted on the positioner of the "Compact"
range.

Unfortunately, when I was there five years ago, a lot of the equipment
associated with the compact range appeared to be in disrepair.

I suspect that you will have a hard time getting testing done here as
security is a big issue. But I could be wrong.


|
| My wife will finish her chemotherapy and
| radiation treatments in March, and since
| she is quite ill, I cannot foresee my being
| available until after that time.
|
| Allowing say 30 days or so for me to
| prepare an antenna, I invite you to make
| the arrangements in Tucson - say April -
| May, 2005 or so - and I will be more
| than happy to join you there.
|
| Is this agreeable?
|
|No, you'll have to make the arrangements.
|
|Determine the cost of the test. I suggest that we find someone who is
|willing and we both can trust to whom I'll send the money the test will
|cost, as proof of my willingness and ability to pay the test fee if the
|antenna meets the criteria. Let me know when the test is to be done, and
|I'll come down and observe. The person who pays will have the legal
|right to make the results public. I agree in advance to do so if I pay;
|I expect you to do likewise.
|
|Roy Lewallen, W7EL

  #4   Report Post  
Old October 15th 04, 12:12 AM
Yuri Blanarovich
 
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W7EL wrote:

I made Chuck an offer a while back, as follows: That if he has the
Raibeam tested at a certified antenna range and the results show a
free-space gain of at least 5.5 dBd (7.65 dBi) with simultaneous 25 dB
or greater f/b ratio, I'll pay the test fee. This is performance less
than he claims and less than he claims his model shows. But so far he
hasn't taken me up on the offer.



Ken, K7GCO got bunch of RAIbeams and put them up, wrote glowing review for 73
Mag. He was impressed with the performance and wanted to figure out why is it
so. He very carefully inserted dimensions into EZNEC model and could not get
agreement. He had to go down to 48. 5 MHz in EZNEC to obtain similar pattern
and parameters as real antenna resonant at 51.25 MHz.

So, maybe modeling doesn't "see" the dual driven elements and critical coupling
well? It is amusing to see the "experts" defending unmistakability of software
(loading coil case etc.)

Yuri, K3BU.us
can we all get alone?
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Old October 15th 04, 01:00 AM
Roy Lewallen
 
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Yuri Blanarovich wrote:

Ken, K7GCO got bunch of RAIbeams and put them up, wrote glowing review for 73
Mag. He was impressed with the performance and wanted to figure out why is it
so. He very carefully inserted dimensions into EZNEC model and could not get
agreement. He had to go down to 48. 5 MHz in EZNEC to obtain similar pattern
and parameters as real antenna resonant at 51.25 MHz.

So, maybe modeling doesn't "see" the dual driven elements and critical coupling
well? It is amusing to see the "experts" defending unmistakability of software
(loading coil case etc.)


I'm sure you're glad, as I am, that Chuck has finally accepted my offer
and agreed to have a real, professional test done, after something like
8 years. The results of the test should put to rest any speculation
about this issue. I'm looking forward to the test and seeing the test
results.

I get feedback from some of my professional customers who have the
capability to test the antennas they analyze with EZNEC. They report
very good agreement between analysis and measurement. Of course, most of
them are real pros in both modeling and measurement. Given the choice of
believing their results or Ken's and Chuck's, I go for theirs. Even
though you might not consider those folks to be "experts", I do.

But by all means, let's look at the test results -- unless you believe
that "critical coupling" results in radiation that conventional test
ranges can't detect but hams can. . .

Roy Lewallen, W7EL


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Old October 15th 04, 02:19 AM
Yuri Blanarovich
 
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I get feedback from some of my professional customers who have the
capability to test the antennas they analyze with EZNEC. They report
very good agreement between analysis and measurement. Of course, most of
them are real pros in both modeling and measurement. Given the choice of
believing their results or Ken's and Chuck's, I go for theirs. Even
though you might not consider those folks to be "experts", I do.


Maybe there are cases when things don't play as figured? Maybe would be of
interest for software author to find out, and if there is a glichand to find
the way to accomodate it? Have you figured out how to model loading coil of
particular inductance and physical size to reflect the real current drop across
it?
Experts said one time that she's flat.

But by all means, let's look at the test results -- unless you believe
that "critical coupling" results in radiation that conventional test
ranges can't detect but hams can. . .

Roy Lewallen, W7EL


Here we go again, W8JI snotty style?
I just mentioned what K7GCO found, in hope that it might shine some light at
the subject and arouse some curiosity about disagreement. If it is
inconvenient, than I am sorry to butt in here. I have no intentions to get
engaged in ****ing contest. Right now I am too busy with new ocean front QTH
next to 170 acre Rhombic antenna farm, DR1 design and business that brings
livelihood. When I get more time, I will get back to work on antennas, setup
test range (across salt water bay) and get into paper models vs. real ones.

Peace!

Yuri, K3BU.us
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Old October 15th 04, 02:37 AM
Roy Lewallen
 
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Yuri Blanarovich wrote:

Maybe there are cases when things don't play as figured? Maybe would be of
interest for software author to find out, and if there is a glichand to find
the way to accomodate it? Have you figured out how to model loading coil of
particular inductance and physical size to reflect the real current drop across
it?
Experts said one time that she's flat.


EZNEC v. 4.0 has a convenient helix creation feature, which allows the
user to quickly make a wire model of an inductor. An inductor modeled in
this way will show a current distribution very close to that of a real
inductor. There are two cautions, however. One is that EZNEC programs
prior to v. 4.0.7 had a bug that would create incorrectly sized wire
(when creating a helix or loop) if wire diameter was specified as AWG
rather than numerical diameter. So be sure to update your program to the
latest version by downloading and installing the latest update from
http://eznec.com/ez40updates. (You've said you don't read the manual, so
you probably aren't aware of these free updates.) The second caution is
that turns should ideally be spaced at least several wire diameters
apart. I have, however, seen good results with spacings down to one wire
diameter. At that spacing, though, EZNEC will overestimate the Q
somewhat (that is, underestimate the loss) because it doesn't account
for proximity effect.

. . .


Roy Lewallen, W7EL
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Old October 15th 04, 04:52 PM
Richard Harrison
 
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Yuri Blanarovich, K3BU wrote:
"Have you figured out how to model loading coil of particular
inductance and physical size to reflect the real current drop across
it?"

Current drop across a coil is E/Z where Z is complex. If a reflection is
involved in the antenna, there are multiple Es involved, perhaps.

Growing or shrinking current through a coil, generates a voltage which
opposes current in the coil. Because of its opposing direction it is
called "counter emf". The change in current in the coil generates the
counter emf. A steady d-c current in a coil generates no emf.

A given length of wire has much greater counter emf when coiled than
when stretched out straight. We say it has more "inductance". It`s
because fields from close-wound turns intercouple. With 3 turns
closewound in a coil, 3 times the lines of force cut 3 turns, so 9 times
the counter emf is generated. As a first approximation, the inductance
varies as the square of the number of turns.

Opposition of counter emf in a coil delays the rise of current in a coil
from the phase of an a-c voltage. In a perfect coil with no resistance,
the delay is 90-degrees or 1/4-cycle. Resistance, useful or useless,
reducees the current delay. Due only to the L/R ratio, the phase delay
imposed by a coil can vary from 90-degrees down to zero.

I did a web search on "r.r.a.a" which produced 590 hits. One of these
was something posted by Roy Lewallen entitled "Inductor Operation". Roy
had measured phase delay in a loading coil. If I understood Roy, he
found no phase delay in an antenna loading coil.

In my opinion, he should find delay even in a coil feeding a dummy load,
especially if the coil is large as compared with the dummy load.

Best regards, Richard Harrison, KB5WZI



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