On Tue,2/10/2015 1:18 PM, Jim Brown wrote:
There is dissipation in a ferrite core choke in the resistance coupled
from the ferrite core. It is the coax shield that gets hot, not the
ferrite (although the heat in the coax may be transferred to the
ferrite material).
I should have added that the above dissipation is the result of common
mode current, NOT differential mode current. The power can be computed
as I squared R or E squared divided by R, where R is the real part of
the choking impedance (Rp in the parallel equivalent circuit), I is the
common mode current, and E is the common voltage across the choke.
This is in addition to the usual dissipation inside the coax
associated with the differential transmitter power. The coax must be
rated to handle both.
73, Jim K9YC
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