> Very interesting discussion. Over the years I have had a
R7 and R8 at various heights from 10' to 90'. With them
above 40' I always had them DC grounded to the mast which
was grounded to the tower which was grounded to earth at the
base. These antennas are different than a 1/4 wave vertical
with drooping radials which I think is what the original
question was about. Assuming one is talking about the 1/4
wave antenna what was the consensus about grounding the
radials to the top of the tower? I must have missed it
somewhere, sri.
The R7, R8, and similar antennas are generally worse than a
groundplane for RF on the feedline. The offset feed creates
huge feedline decoupling problems. The radials should never
be grounded in any vertical with a small radial system, in
particular with an offset feed small radial system.
Grounding is a cure for feedline common mode current
problems only by random luck. If it helps, it helps mostly
because it masks symptoms caused by feedline common mode
currents.
The real fix is isolating the feedline and mast from the
antenna currents.
73 Tom
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