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[Towertalk] Re: EZNEC 3.0 question

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Subject: [Towertalk] Re: EZNEC 3.0 question
From: jirka@jimaz.cz (Jiri Sanda)
Date: Mon, 20 May 2002 12:14:17 +0200
I do agree, just a remark:
EM "pretends" it's engine is a competition to NEC-4, in real life very 
hardly available to us - the public. What was written on other places - 
it is in most cases; we hams might use (i.e. antennas of Yagi and loop 
type) even more precise than NEC-4.
But the shell, as they deliver it, is as I have written, far in 
friendliness to AO, EZNEC, NEC-WinPro etc.

I have bought it a while ago and as an analytical tool I find it 
excellent. I have even suggested to EM some improvements to the shell, 
but their response was something like: if you find some mathematical 
problem we are more than happy to solve it but we do not care for the 
shell - we are the scientists which developed this very good shell.....

OK still my admiration, since what I have modeled since and realized the 
match was always within accuracy of the measurement (and this never 
happens at least to me with YO 6.55 or EZNEC!!!) (T32RD antennas - some 
of them quite complex (4 + 4 element duobander on 8m boom for 18+24 
etc...)  some of OK1RI/OK1RF antennas + OK1KIM 2m-farm today 161 el. 
hopefully until end of june 306 elements - if interested have a look at 
www.qsl.net/ok1kim (+ others)

73 !

Jiri
OK1RI

P.S. I am afraid we are again off towertalk so lets hope we won't be 
punished !

Jan Erik Holm wrote:

> Another comment: Below I mean NEC 2, or 3 or 4 calc
> engine.
> And even NEC2 has a problem with close spaced wires
> so for designs like that I never ever would use anything
> else but NEC2-4 stuff.
> 
> 73 Jim SM2EKM
> ---------------------------------------------------------
> 
> Jan Erik Holm wrote:
> 
>> Problem with YO is that the calculating engine is far too simple,
>> you really have to be carefull with what you are doing.
>> In any case, I would not trust YO alone, I would confirm
>> my design on a program using the NEC calculating engine.
>>
>> 73 Jim SM2EKM
>> --------------------------------------------------------------------
>>
>> Jiri Sanda wrote:
>>
>>> Can someone tell me what is the improvement from YO 6.55 to YO 7.0.
>>>
>>> Is it already able to model OWA type Yagis - i.e. would it model 
>>> correctly the close elements ? What impedance you get if you model 
>>> NW3Z design. 6.55 gives you something like 35 Ohms while 
>>> mathematically excellent but user unfriendly EM-broadcast 
>>> professional gives you 48 Ohms which is the reality.
>>>
>>> 73 !
>>>
>>> Jiri
>>> OK1RI
>>
>>
> 
> 
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