Thread: Baluns?
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Old September 2nd 08, 04:07 PM posted to rec.radio.amateur.antenna
JB[_3_] JB[_3_] is offline
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First recorded activity by RadioBanter: Apr 2008
Posts: 543
Default Baluns?


"John Smith" wrote in message
...
JB wrote:
My take on CM chokes is that they are best on TV coax to keep energy on

the
shield from bringing trouble to the TV chassis. On a transmitting

antenna,
the idea is to enforce a high impedance bump somewhere to set the

resonant
length other than what it wants to be. That might not contribute to
efficiency even if it prevents the coax from being part of the antenna.

If
the antenna is in resonance, there won't be any coax radiation and no

Choke
is really needed. My point is, you are best not needing one, but if

that is
what you need to put the current out on the wire, or out of the shack.

OK.
Of course high gain antennas have a pattern to protect, but does it

matter
all that much for anything up to a 3 element yagi? High currents and
voltages on the coax are to be avoided because that is where your loss

will
be.



That is so bizarre; I just don't know where to begin in the description
of how and how much!

Regards,
JS


Ya I know, I didn't get into the how. How much is the first thing you need
to be aware of.