Topband: Coax Choke Balun

[Roger Parsons]

Jim Brown K9YC wrote:

"There is a MAJOR advantage to using a ferrite core -- it makes the 
choke RESISTIVE rather than inductive."

With respect, I don't believe this to be correct. A ferrite/dust iron cored inductor has exactly the same basic characteristics as an air cored inductor. It has inductance, loss resistance and distributed capacitance.  For a choke (which is another word for a particular use of an inductor) to appear (almost) purely resistive it must be operated as part of a resonant circuit, or be such a poor inductor that the loss resistance is predominant! 

73 Roger
VE3ZI