On 11/14/2010 11:11 AM, Dr. Gerald N. Johnson wrote:
and they might not prevent feedline radiation and reception.
There are two causes of feedline radiation/reception -- common mode
current and conductor spacing. A common mode choke AT THE FEEDPOINT can
essentially kill the radiation due to common mode current unless the
feedline is some multiple of a half wave, in which case an additional
choke placed along the line to act as an "egg insulator" to make it less
than a half wave would kill the remaining current.
The choke will, of course, have no effect on radiation due to spacing,
which results from the differential signal.
73, Jim K9YC
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