On 1/26/2012 9:19 PM, Rick - DJ0IP / NJ0IP wrote:
I agree Jim, but are you implying that you cannot use openwire to feed an
unbalanced antenna?
No, I'm simply observing that the simple act of using parallel conductor
line does not make an antenna, or a system, balanced. Lack of balance
does not affect loss, but it DOES cause the line to carry common mode
current, which in turn causes the line be part of the antenna, which
causes it to both radiate and receive. If the line runs near noise
sources, it will receive those noise sources. If it runs close to your
living room (or your neighbor's living room) it can radiate RF into
entertainment gear, telephone, and computer speakers. And, as with coax,
we can kill common mode current on the feedline with a suitable ferrite
choke at the feedpoint.
73, Jim Brown K9YC
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