> Personally I consider the shield of the coax (connected to
> the radials) to
> be one of the radials so why choke it anyway? Chokes at
> that point just add
> loss to the system when they try to block the current
> induced on the shield
> from getting back to the base of the vertical.
Not true.
With a small elevated ground system any path to earth
reduces field strength. That's etched in stone, it isn't a
guess.
While the amount of loss varies can vary it always adds some
loss. This is because the voltage to ground at the common
point is not even close to zero, so current flows through
the shield into the station or lossy earth along the coax
and that represents lost power. It also results in noise
egress back into the antenna from the station. It means the
coax radiates and that almost never is a good thing.
Elevated radials are such a mess for stray RF, pattern
distortion, bandwidth, and efficiency I would only consider
them as a last resort. A second very good reason (one of the
best reasons actually) to use them is if you are competing
against me in a contest.
73 Tom
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