Hi John and Group!
On Mon, 20 May 2002, john sexton wrote:
Hi Sasha,
Putting in the same antenna details as before,
the new formula gives 38 ohms, still too low by a factor of over 2,
but much better than with the first formula.
I just compare the formula to NEC-2 (Sommerfeld ground) modeling and get
such a result:
H=20m, l=100m, s=1mSm/m
h Rin Rrad Rg Rg formula/NEC
m NEC NEC formula
0.5 6.67 0.13 6.54 7.47 1.14
1 4.97 0.12 4.85 5.43 1.12
2 3.31 0.11 3.20 3.52 1.10
3 2.42 0.10 2.32 2.51 1.08
4 1.83 0.08 1.75 1.87 1.07
It seems differences is due to not enought segmentation in modeling (1
meter of segment length). I can't do better segmentation because of my
computer is not so good...
73 de RA9MB/Alex
http://www.qsl.net/ra9mb
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