[TowerTalk] EZNEC- needs improvement

[Jim Brown]

On Sun, 5 Apr 2009 15:29:43 EDT, RLVZ at aol.com wrote:

> 
>RadioIR (below) states how EZNEC is not always accurate.

It is well known that EZNEC is not good at modeling antenna elements in close 
contact with the earth. 
> 
>A few weeks ago, I posted an e-mail on how in dozens of side by side  
>comparisons my single 40-m. 1/4 wave vertical near saltwater worked at  least as 
>well, if not better, than a new Cushcraft XM-240 Shorty-Forty at  90' in all 
>directions the vertical looks over saltwater: Europe, Africa,  and South America.  
>Computer modeling indicated that the Shorty Forty  should have about a 10dB 
>advantage over the vertical with  saltwater.  (and the vertical has a minimal 
>radial  system: two 1/4 radials and a single 2" copper  strap saltwater)

HANG ON A MINUTE!  Salt water is a VERY special case. Verticals are VERY well 
known to perform extremely well next to salt water, FAR better than they do over 
the more ordinary earth where most of us live. 

>My hope is that more actual side by side antenna comparison  information can 
>be used to improve modeling accuracy.

My comments comparing verticals and dipoles are on the basis of BOTH NEC modeling 
and on the air comparisons during contests on a LOT of signals. I have yet to find 
any significant disagreement between NEC models and what happens on the air with 
MY antennas. 

73,

Jim Brown K9YC