> reference on the OK1RR web page that came from an unknown author. This
> author said that a ground rod should not be used at the junction point
> of a radial system. He said that when the ground rod was not at the
> radial junction point of the anrtenna that he was using the Feild
I think that must have come from a discussion about elevated radials.
With a small number of elevated radials, there is considerable
voltage between the coax shield connect at the antenna and earth. If
you ground that point to earth in any manner, it decreases the field
strength.
That is why we should always use a choke balun at the feedpoint, and
never ground any part of the system out at the antenna to earth.
The same thing happens with a small groundplane. Most of the small
commercial groundplane antennas I designed have the groundplane and
coax shield insulated from the mast, and a choking system to keep
current off the coax shield.
If you have even 20 or 30 radials, the ground rod or grounding the
coax shield has no effect.
The elevated and small GP problem, by being taken out of context,
obviously is spilling over into areas where it does not apply.
73, Tom W8JI
W8JI@contesting.com
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