The most directly relevant question is E9C15:
What strongly affects the shape of the far-field, low-angle elevation
pattern of a
vertically polarized antenna?
A. The conductivity and dielectric constant of the soil in the area of
the antenna
B. The radiation resistance of the antenna and matching network
C. The SWR on the transmission line
D. The transmitter output power
The correct answer (A) doesn't define what is meant by "in the area of
the antenna". To that extent it is a badly-worded question. Fortunately,
you can arrive at answer A through a process of eliminating the others.
However "Gordo's" advice contains no such ambiguity. He says: "Well,
that would be the conductivity and dielectric constant of the soil in
the area *just below the antenna*." [my emphasis]. That is plainly
wrong, as we have seen.
It seems a shame if students have to accept technical error in order to
pass an exam.
73,
Steve G3TXQ
On 06/01/2011 12:11, geoffrey mendelson wrote:
On Jan 6, 2011, at 1:26 PM, Steve Hunt wrote:
ARRL Extra Class License Manual, Page 9-8 Effects of Ground and Ground
Systems:
<http://www.ncvec.org/page.php?id=351>
Here is the actual question pool. You are welcome, if you wish, to
read through it and see which questions pertain to the subject, and if
they do, does the quote from "Gordo" or the competition (ARRL) help
you pass the test.
Note that as far as I know, and I may be wrong, you can't challange a
test result based on the accuracy of a question. Anyone can challenge
a question in the pool, and if succcessful, the question will either
be deleted, amended or replaced, but until it is, answers that do not
match published correct ones will be counted incorrect and there is no
way to appeal.
Geoff.
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