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On Thu, 30 Jun 2005 01:30:39 GMT, "Tom Donaly"
wrote: Convolution is a mathematical stunt you can perform with two functions: f(x)* g(x) = (integral from 0 to x) f(t)g(x-t) dt. At least that's how it's explained in Schaum's Outline book _Differential Equations_. It's pretty tough to see how it relates to power in a transmission line. Maybe someone has a use for it there. 73, Tom Donaly, KA6RUH **** Yes Tom Convultion was the wrong term to use. I made a mistake because i type as i think and on occasion hit send before i reread what i have written. I still contend that a sinusoidal wave travelling down a coax is comprised of perpendicular(orthogonal) E and H fields. The these vector fields that induce sinusodial current and voltage potential vectors in and between the shield and center conductors as the wave travels. Both the source and reflected waves are comprised of two vector fields, E and H. Granted this is true only when the load reflection coefficient is not zero. In that case of zero, then there is no reflected power. It is possible to derive from the vector current and vector voltage a magnitude of those vectors and thus a produce two scalar quantities that can be pluged into Ohm's Law and derive an instantaineous power at a given time and position on the coax. That both source and reflected sinusoidal current and voltage can have derived scalar values. These values can be directly added. This all started from an SWR question. I contend that the instantaineous power at any given time and position of the coax can be expressed as the sum of the magnitudes or scalar quantities of the source and reflected powers. If you are wanting just the magnitudes of the power, then this should work. james |