Re: what a 1:1 choke balum used for

John Popelish wrote:
. . .
As I understand common mode current, it is the net imbalance between the current through the center conductor and the current through the shield.

If you consider the sum of the physically separate currents on the inside and outside of the shield to be the current "through the shield", that's correct. And it's equal to the current on the outside of the shield.

>. . .

Roy Lewallen, W7EL
.

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