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Old December 10th 10, 08:49 PM posted to rec.radio.amateur.antenna
K1TTT K1TTT is offline
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First recorded activity by RadioBanter: Apr 2010
Posts: 484
Default What does this mean?

On Dec 10, 4:49*pm, Richard Clark wrote:
On Fri, 10 Dec 2010 05:55:15 -0800 (PST), K1TTT
wrote:

it is actually more
correct to call them chokes than baluns since they really just try to
choke off the current on the shield of the coax at the feed point.


Some balance needs to be returned to this (pun intended). *The
expression BalUn is first and foremost found in what this word means
in full: Balance/Unbalanced and THAT is the principle transformation.
Turns ratio may come, but that is variable (2:1, 4:1, 6:1...) to a
design that must first meet the requirement of isolating one side that
is balanced from the other side that is unbalanced.

This is achieved in choking common mode currents - hence the BalUn
must effectively present choking action to meet this principle
transformation.

73's
Richard Clark, KB7QHC


here comes the troll statement...

currents are always balanced and there is no transformation. the
currents in a coax are already balanced, on the inside. the action of
the choke is to prevent current from flowing on the outside of the
shield back to the inside at the antenna feed point. this forces the
return path to be the other half of the antenna if all works
properly.

let the balun wars commence!