On Thu, 29 Mar 2007 16:32:31 -0700, Jim Kelley wrote:



Walter Maxwell wrote:

Sorry Jim, but I take exception to your statement, "If redirection of energy takes place,
it takes place by reflection - not interference."

Hi Walt -

I am preparing a more lengthy response, and in the interim let me say
that I'm sorry you take exception. But my statement is nevertheless
honest, truthful, and factual. What part of it do you feel is
contradicted by physical laws?

Hi Jim,

It's been a long time since we discussed this point, so I've forgotten how we ended up on it. The part I feel
is contradicted is that when total re-reflection is caused without a total discontinuity such as a physical
short or open circuit, it is caused by resultant of the interference between the forward and reflected
voltages and the interference between the forward and reflected currents. When the phase relationships between
the respective voltages and currents are correctly adjusted to achieve an impedance match, the resultant is
either a virtual short circuit or a virtual open circuit, which causes total re-reflection of the waves
reflected from the mismatched load terminating the line. Consequently, the interferences cause the
re-reflection.

Are you saying that this explanation of the re-reflection concept is incorrect?

Walt

I am familiar with your chapter 23. You sent me a copy of it quite
some time ago. I had hoped that our work together might have changed
your point of view about this.

73, Jim AC6XG

It is the interference between the forward and reflected voltages and beween the forward and reflected
currents that yields the resultant voltage and current values of rho at the matching point which produces
either a virtual short or a virtual open circuit that causes the re-reflection. I have shown this to be true
in my QEX article of Mar/Apr 1998, entitled, "Examining the Mechanics of Wave Interference in Impedance
Matching. It is also Chapter 23 in Reflections 2.

Using the complex values of rho I have shown the magnitude and phase relationships of the aforementioned
voltages and currents at the stub point that result in a virtual open circuit at the stub point to waves
reflected from a 3:1 mismatched load. The result is no reflections on the line between the stub and the
source, but a 3:1 SWR on the line between the mismatched load and the stub. If you don't have a copy of this
article please let me know and I'll send you one via email.

Walt, W2DU