Owen wrote:
. . .
This leads me to think that measurement of the imbalance current at a
single point might not give the "big picture". I found scenarios where
inserting an imperfect balun increased the current at a point (it
changed the magnitude of the standing wave and more importantly moved
the current minimum), so I could see someone with a handy-dandy
current probe measuring such a situation and insisting they have proof
the baluns don't "work".

This situation lends itself well to modeling, where it's readily
illustrated. While it's often difficult to exactly model a given
physical setup, modeling allows us to control the variables and clearly
see what's happening. We can often apply this knowledge and insight to
real situations.

Roy Lewallen, W7EL

On Mon, 27 Jun 2005 00:33:52 -0700, Roy Lewallen
wrote:

Owen wrote:
. . .
This leads me to think that measurement of the imbalance current at a
single point might not give the "big picture". I found scenarios where
inserting an imperfect balun increased the current at a point (it
changed the magnitude of the standing wave and more importantly moved
the current minimum), so I could see someone with a handy-dandy
current probe measuring such a situation and insisting they have proof
the baluns don't "work".

This situation lends itself well to modeling, where it's readily
illustrated. While it's often difficult to exactly model a given
physical setup, modeling allows us to control the variables and clearly
see what's happening. We can often apply this knowledge and insight to
real situations.


Exactly. Nothing I wrote was intended to comment adversely on your
quoted paper, it is interesting and relevant... just a pity the
results tables are not 100% legible.

Modeling shows me the risks of single point measurement, and I agree
entirely with your final statement "While it's often difficult to
exactly model a given physical setup, modeling allows us to control
the variables and clearly see what's happening. We can often apply
this knowledge and insight to real situations". A whole lot of insight
can be gained in a very short time.

Owen

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