Using NEC-2 to attempt a model of my entire station, with particular
attention to the 80-meter K3LR array that is suspended from the tower. I
have a couple of specific questions:
1. What is a reasonable value to assign as the loss resistance at the base
of a tower connected to real/MiniNEC ground? The tower in question is Rohn
25 with 3 x 8' ground rods, one at each leg, attached to the tower with #4
copper wire and well-maintained connections.
2. Similarly, what is a reasonable load R to assign to the ground at the
outer ends of guy wires, where they are grounded through a single 8-foot rod?
3. Has anyone had any experience with the method of determining ground
conductivity that was suggested, I believe, by John Belrose? He described
suspending a dipole low above ground, measuring the feedpoint impedance and
resonant frequency, and then tweaking the ground parameters in NEC-2 to
obtain the closest match. If so, what frequency did you use and how low
did the antenna need to be to achieve the needed sensitivity to ground
parameters?
73, Pete N4ZR
The World HF Contest Station Database was updated 11 April 03.
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