Kees,
What else is around your verticals? Just the fact something is not resonant
does not mean it isn't a problem.
To my ashtonishment, vertical 1: 28-j328 Ohm and vertical 2: 12-j320 Ohm
both on 1825 kHz.
The vertical with the smallest radial system has the lowest earth
resistance (around 5 Ohms, estimating 7 Ohms radiation resistance for a
21m high vertical).
The oldest vertical (nr1) with 50 radials seems to have more than 20
Ohms.....
Since it is a system with standing waves, even on the radials, impedance at
the base might not represent true ohmic losses.
I measured the earth conductivity with the 2-conductor method and I found
that the soil under vertical nr 2 has better conductivity (maximum found:
25 mS/m) compared to vertical nr
1 (maximum: 21,5 mS/m).
If that is a low frequency measurement, I have never seen a measurement like
that mean very much on HF or higher. Typically you are measuring rod contact
and 50/60 Hz more than RF behavior.
If it is an RF measurement, like rod centered on a large screen and measured
against the screen, it is much more useful but still not always accurate.
I have little faith in two rods, and no faith in something done on power
line frequencies.
What you measure might not mean anything for performance.
73 Tom
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