On Thu, 03 Jun 2004 12:44:10 -0700, Jim Kelley wrote:



Cecil Moore wrote:

Walter Maxwell wrote:
Cecil, the following is a direct quote from Steve's Comm Quart Article, Oct
1999:
"For the impedance matching network to 'work', this analysis must demonstrate
that the steady-state traveling backward power developed at the matching network
input is equal in magnitude but 180 degrees out of phase with the initial power
reflected at the matching network input. For this to occur Vback must be the
negative of VR. In this case ALL POWER TRAVELING BACKWARD TOWARDS THE
TRANSMISTTER WILL BE CANCELED, resulting in the steady-state matched condition."

Joules/sec possesses phase? Joules/sec can be canceled?

Hi Jim,

Of course you're right, but that's not the point. The point is that reflected
energy is not canceled, nor does it disappear at the matching point, instead it
is re-reflected into the forward direction. This is the point that Steve
apparently doesn't understand. And this is the reason his power budget is
incorrect in his 3-part article, he ignored the energy appearing at the match
point, assuming that it disappeared, though his word is 'canceled'.

I thought my emphasis with capitalization would contain the necessary info, but
I can see now that I should have made the emphasis show that the 'canceled
energy' was erroneous, because energy cannot be canceled. In this case it is
re-reflected, a concept Steve ignores.

Therein lies part of the problem with thinking that the unit
(Joules/sec) moves along a transmission line. Energy in Joules moves.
(Joules/sec) of power does not.

73, Jim AC6XG

Sorry, Jim, I put my response in the wrong place.

Walt