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Old August 3rd 05, 05:34 PM
Richard Clark
 
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On Wed, 3 Aug 2005 09:18:38 -0700, "greg knapp 5"
wrote:

I really can't answer how important the coupling factor is because I have
never dealt with this factor before.


Hi Greg,

Frank has been carrying a lot of water for you in this regard. I
would point out (and he has stated as much) that his numbers are for a
load of 600 Ohms. Now, any mismatch will not have any impact on the
coupling, but the load's balance to earth will and Frank has done no
study of induced Common Mode currents. Given that there is a world of
possible imbalances possible, it is hard to know where to go from
there.

There is also a world of probable imbalances too. The antennas you
are feeding are far more likely the source of the problem of coupling
between lines than are the lines' proximity. However, proximity only
magnifies the problem. Still and all, even the worst imbalance is
unlikely to pose significant issues. It might be problematic for a
VOA feed of 500KW with leakage of their European service into their
African service, but you are not in that class (and they probably now
how to keep their antennas balanced too).

73's
Richard Clark, KB7QHC