There is considerable research that indicates that grounding the elevated
radials for RF harms the pattern more than just a little... At -1dB hit, and
likely more... If the vertical is only +2.7dBi gain to begin with a -1dB hit
is significant... At my station another dB is roughly $2000 so losing a dB is
significant to me...Worse than the loss is the distortion of the expected
pattern... When working weak signal DX 1db is often the difference between
making the Q and not making it... For rag chewing with the locals on 75 meters
1dB is meaningless. and you might as well ground everything.
If DC grounding the radial system is important to you then do it through a
husky parallel tuned circuit so that the RF on the radial is maintained above
ground potential.. And put a common mode choke on the coax at the feed point,
and if necessary repeat the choke 1/8 wave back from the antenna...
denny / k8do
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