Dear people, I experience a situation that confused me a little bit.
I have a vertical with 60 fence wire buried radials 1/4 wave long plus a ground
rod.
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 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 them except
one which also had a ground rod.
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 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 was that for some
reason most of the radials had dissapeared.
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.
Question 1: 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 and besides if
the soil was so dry why the ground road was collecting so much current from it?
Any guess what could be going on ?
Question 2: Could it be possible that radials could have been eaten by the soil
and I am having very short ones ?
I am planning to add another 60 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 3: 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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Topband Reflector
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