"A specific description from you about the ground used for radials would be
very interesting.
73, Guy K2AV"
Guy and all, Unfortunately the only data about terrain is
almost flat farm land conformed by humus and neutral PH.
Before having the tower and just for fun, I decided to play with Rudy N6LF
measurements, against an inverted L, and to my surprise, I got extremely
similar results about shortening radials and measuring the current of each of
them at the antenna Base. Also, I did FS measurements at ground level at about
300 mts which acompanied the increase in current at the base of the antenna.
Also I repeated the test of having 4 x 1/4 wave radials lying on the ground,
measuring its current and FS. Then, raising them up in 3 step up to 85 cm from
the ground and the change in FS measurement related directly with Rudy
measurements....a huge change.
Finally a comment about "lying on the ground" that I shared with Rudy, if you
have 20 or less radials (I didn´t do it with more) and shorten them for maximun
current at the base, which in my case was accompanied by an increase in FS,
they are quite sensitive to the distance from the ground specially the last 1
or 2 mts. What I found was that if the grass move your radial up let say 5 cm
in the last couple of meters, and the next one is just lying on the ground,
even though equal physical length will have different currents ergo different
length to both have the peak at the antenna base.
As the number of radials increase, the radial length increased and that
sensitivity gets smaller.
Good dx to all.... Eddie, LU2DKT
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