Are you disagreeing with something I said, or just adding a note? If
disagreeing, what again was it that you disagree with?
The source voltage and internal impedance have nothing to do with the
reflection coefficient at any point. The forward and reverse voltages
are indeed known if one knows, for example, the line Z0 and the load
impedance and the load power, voltage, or current. It's not necessary to
know the source impedance to find these values, the forward and reverse
voltages, or the reflection coefficient.
Roy Lewallen, W7EL
Reg Edwards wrote:
I disagree with this. When applied to transmission lines, the (voltage)
reflection coefficient is, as far as I can tell, universally defined as
the ratio of reflected to forward voltage to reverse voltage at a point.
So a reflection coefficient can be, and often is, calculated for every
point along a line, not just at discontinuities or points of actual
reflection.
This can be done with nothing more than the knowledge of the
values of forward and reflected voltages at the point of calculation.
=============================
Sorry! Just to continue and further confuse the haggling, the forward
voltages are unknown because one does not know, in the case of amateur
systems, what is the internal voltage and internal impedance of the
transmitter.
It is this unknown voltage and internal impedance which the so-called SWR
(Rho) meter merely ASSUMES.
|