Dear people, I experience a situation that confused me a little bit.
I have a vertical with 60 iron fence wire buried radials 1/4 wave long plus a
ground rod. I installed it 2 years ago lying on the ground and now they are
buried.
Prior to the contest I decided to check the buried radials of my vertical. I
have bundles ranging from 4 to 7 radials connected to a square ring around the
base of the tower. I provided 20W input and I measured the current entering
each of the bundles which is a procedure I have done many times.
To my big surprise there was little to no current entering most of the bundles
except one which also had a ground rod besides the radials.
This bundle took aprox 80% of the total current. Then I decided to measure the
current entering the ground road and it was aprox 100% of the total for that
bundle.
This situation was the opposite I always had measured before where the ground
rod practically had insignificant current.
2 months had passed without any rain so I tried to spread some water around a
radius of 4 meters but situation didn´t change dramatically but yes an small
increase in all radials current
That night I thought a lot of possibilities but the strongest one was that for
some reason most of the radials had dissapeared or at least have been reduced
to short ones.
Next day we have 27mm of rain. Another surprise, everything back to normal. I
had current in all bundles and almost nothing into the ground rod.
I expected that having 60 radials it should not matter if it rains or not. I
expected to have a relative good shield of the ground
Question 1: Any guess what could be going on ?
Question 2: Is it a normal situation? Does anyone experience the same?
Question 3: Could it be possible that radials could have been eaten by the soil
and I am having very short ones? and that made them so much soil conductivity
dependent?
Question 4: if the soil is so dry why the ground rod collect so much current
from the same soil?
As I have no explanation so far, I am planning to add another 60 radials and
for a reason of cooper cost I am planning to use what I think should be similar
to what I read here many times as WD1. It is for exterior telephony drop
consisting of a pair of 0.8 mm of stiff wire which looks like iron covered by
cooper and both separated by 3mm of a very heavy plastic. I measured 13 ohms of
DC resistance in 60 mts of wire.
My plan is to split the 2 wires and use them as radials.
Question 5: It is a good or a bad idea to use this kind of wire instead of
fence wire?. Cooper will be the last option of course
Many thanks in advance for your opinions.... Eddy, LU2DKT
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