Hi All,
Since posting the condensed radial info I've received an email from a
personal friend who has had experience measuring performance for 'Y' or
crows feet extensions to radials far away from the base.
He says that this was on a broadcast station installation. He tried a few
different tests: He measured base current and then added a 'Y', then tried a
ground rod at the end, even connected his truck to the end :-) and in all
cases the base current was slightly reduced indicating decreased efficiency.
My concern is that I have put in full sized radials for all three vertical
elements in all directions, rather then using a bus to terminate them at
the 1/2 way points between each element. They all overlap. I tied each
radial once to another somewhere in the system, so that it forms a matrix
grid all over the field. I see no indications of parallel resonances based
on a smooth swr curve...
Can I expect a degradation from all these 'Y' type connections or is this an
exception, a non-event not to worry about? I could easily start cutting
wire and return it to a conventional bus configuation, but this would mean
taking out a heck of a lot of wire already laid down.
Also... I have a 2,200' tower lightning protection ground system running
18" underground in the cable trenches to the various towers. Is it desirable
to tie this into the vertical ground system or does it come under the
category of ground rods?
I realize some of this is possibly cutting hairs or hard to answer, but so
far there's been some good answers and I will continue to modify my project
based upon them.
Any opinions?
Thanks.
Tom, K1JJ
BTW, I've received some additional data showing elevated radial tests. Quite
convincing as to their success. It's enlightning to see the varied opinions
and info flow!
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