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Old November 9th 07, 07:02 PM posted to rec.radio.amateur.antenna
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Default OWA modeling and NEC-4 information

I've tried to model some OWA Yagis using MiniNEC or NEC-2 interfaces, like
Eznec and 4NEC2 (a friend used also AO and YO), but the results are
disappointing, especially regarding the impedance, which is one of the most
important result for OWA.
Even entering real antennas, like the NW3Z 6 elements OWA yagis, the results
are not correct...
For this and other reasons, I'm thinking about buying NEC-4 engine from LLNL
and I would to know if this software is copy protected with some hardware
dongle or software key or not.
I read the licensing documents and it seems that there is no copy protection
supplied, is it true?
73 and thanks
Guido, ik2bcp


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Old November 9th 07, 07:17 PM posted to rec.radio.amateur.antenna
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Default OWA modeling and NEC-4 information

I've tried to model some OWA Yagis using MiniNEC or NEC-2 interfaces, like
Eznec and 4NEC2 (a friend used also AO and YO), but the results are
disappointing, especially regarding the impedance, which is one of the most
important result for OWA.


Really? When I built my OWA's (6 el 28 Mhz, also a 6 el 21 MHz) I used
EZNEC (NEC2). The SWR curve of the final antenna matched pretty well with
the modeling and I didn't need to adjust anything on the final antenna.
I used DX Engineering element brackets which insulate the element from
the boom.

Tor
N4OGW
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Old November 9th 07, 11:20 PM posted to rec.radio.amateur.antenna
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Default OWA modeling and NEC-4 information

Really? When I built my OWA's (6 el 28 Mhz, also a 6 el 21 MHz) I used
EZNEC (NEC2). The SWR curve of the final antenna matched pretty well with
the modeling and I didn't need to adjust anything on the final antenna.


Hi Tor,
problems begin when the first director is too close to the dipole...
How is the distance between DE and D1 in your antennas and, could you,
please, send me your .ez files, just to see your antennas.
Thanks and 73
Guido, ik2bcp


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Old November 12th 07, 02:43 PM posted to rec.radio.amateur.antenna
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Default OWA modeling and NEC-4 information

Hi Tor,
problems begin when the first director is too close to the dipole...
How is the distance between DE and D1 in your antennas and, could you,
please, send me your .ez files, just to see your antennas.
Thanks and 73


I will look up the design numbers...qrx

Tor
N4OGW
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Old November 9th 07, 08:11 PM posted to rec.radio.amateur.antenna
art art is offline
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Default OWA modeling and NEC-4 information

On 9 Nov, 11:02, "Guido" wrote:
I've tried to model some OWA Yagis using MiniNEC or NEC-2 interfaces, like
Eznec and 4NEC2 (a friend used also AO and YO), but the results are
disappointing, especially regarding the impedance, which is one of the most
important result for OWA.
Even entering real antennas, like the NW3Z 6 elements OWA yagis, the results
are not correct...
For this and other reasons, I'm thinking about buying NEC-4 engine from LLNL
and I would to know if this software is copy protected with some hardware
dongle or software key or not.
I read the licensing documents and it seems that there is no copy protection
supplied, is it true?
73 and thanks
Guido, ik2bcp


Guido
If you can't make them work then I would forget about computor
programs.
They obviously are not your cup of tea despite how many people use
them with success. You would be better off finding out what you are
doing wrong than sending money at the problem.
Art
Art



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Old November 9th 07, 11:24 PM posted to rec.radio.amateur.antenna
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Default OWA modeling and NEC-4 information

"art" wrote in message
oups.com...
Guido
If you can't make them work then I would forget about computor
programs.
They obviously are not your cup of tea despite how many people use
them with success. You would be better off finding out what you are
doing wrong than sending money at the problem.


Hi Art,
do you mean that NEC-2 works fine even with D1 very close to DE?
Other reasons for buying NEC-4 would be obtaining useful results with wires
near ground and connected wires with different diameters.
Thanks and 73
Guido, ik2bcp


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Old November 9th 07, 11:56 PM posted to rec.radio.amateur.antenna
art art is offline
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Default OWA modeling and NEC-4 information

On 9 Nov, 15:24, "Guido" wrote:
"art" wrote in message

oups.com...

Guido
If you can't make them work then I would forget about computor
programs.
They obviously are not your cup of tea despite how many people use
them with success. You would be better off finding out what you are
doing wrong than sending money at the problem.


Hi Art,
do you mean that NEC-2 works fine even with D1 very close to DE?
Other reasons for buying NEC-4 would be obtaining useful results with wires
near ground and connected wires with different diameters.
Thanks and 73
Guido, ik2bcp


I don't have any problems using AO which your friend has!
Have you looked at W4RNL pages on the antenna modelling?
He may very well have all the data you need on that antenna.
Art

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Old November 10th 07, 12:17 AM posted to rec.radio.amateur.antenna
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Posts: 5
Default OWA modeling and NEC-4 information


"art" wrote in message
ups.com...
I don't have any problems using AO which your friend has!
Have you looked at W4RNL pages on the antenna modelling?
He may very well have all the data you need on that antenna.
Art


Hi Art,
if you model this antenna (http://nw3z.contesting.com/20mon48'.htm) with
AO, you obtain the same results?
Thanks and 73
Guido, ik2bcp


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Old November 10th 07, 12:10 AM posted to rec.radio.amateur.antenna
art art is offline
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Default OWA modeling and NEC-4 information

On 9 Nov, 15:24, "Guido" wrote:
"art" wrote in message

oups.com...

Guido
If you can't make them work then I would forget about computor
programs.
They obviously are not your cup of tea despite how many people use
them with success. You would be better off finding out what you are
doing wrong than sending money at the problem.


Hi Art,
do you mean that NEC-2 works fine even with D1 very close to DE?
Other reasons for buying NEC-4 would be obtaining useful results with wires
near ground and connected wires with different diameters.
Thanks and 73
Guido, ik2bcp


Guido,
Try looking for the "constant impedance antenna" which I put on the
net after I applied for a patent on it just before they came
out with that OWA antenna. W4RNL looked at OWA extensively and
found that it wasn't all that it was put up to be.
The "constant impedance antenna" is based on a closely coupled loop
to the driven element and certainly broadens the band width.
The OWA antenna is very similar to mine but as I remember they
changed the driver position compared to mine.
For those getting ready to flame, yes I did apply for a patent
well before the OWA came about and described it on this
newsgroup.
Art
Art

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Old November 9th 07, 08:23 PM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Mar 2007
Posts: 801
Default OWA modeling and NEC-4 information

Guido wrote:
I've tried to model some OWA Yagis using MiniNEC or NEC-2 interfaces, like
Eznec and 4NEC2 (a friend used also AO and YO), but the results are
disappointing, especially regarding the impedance, which is one of the most
important result for OWA.
Even entering real antennas, like the NW3Z 6 elements OWA yagis, the results
are not correct...
For this and other reasons, I'm thinking about buying NEC-4 engine from LLNL
and I would to know if this software is copy protected with some hardware
dongle or software key or not.
I read the licensing documents and it seems that there is no copy protection
supplied, is it true?



Yes it is true. You could run it on as many of YOUR computers as you
care to.

No copy protection, just an organization with lots of expensive lawyers
with time to hunt you down. Not to mention that the software is export
controlled, so the crew of potential hunters includes the government,
which has very deep pockets indeed. When you get a copy, you sign a
license (not a click agreement.. a real piece of paper that you have to
send them) agreeing not to redistribute. If you happen to redistribute
to someone who shouldn't have the software, then you get to find out
(the hard way) all about the International Tariff on Arms Regulations
and similar export controls.


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