"Reg Edwards" wrote in message
...
Walt,

As suggested, I looked up your paper in your website about "Additional
power lost in trans-lines due to SWR."

It is applied only to coaxial lines, of course, because the usual SWR
meter cannot be used on balanced twin lines. Actually it applies to
all lines.

Reg, my Appendix does not apply only to coaxial lines. Like you also said,
it applies to all lines. Balanced twin lines also have SWR, as you already
know, but my words didn't limit measurements of SWR only to coaxial lines.
There are ways of measuring the SWR on open-wire lines other than
instruments limited to use on coaxial lines.

I think your calculating formula is an approximation. It is due to the
SWR meter discarding all information about the PHASE ANGLE of
reflections. ie., the angle of the reflection coefficient (Gamma) from
which you have used to calculate SWR in your explanation.

No approximations at all, Reg. As you know, reflection is the cause of SWR,
not the reverse. Further, the coefficient of the reflection that results in
SWR is the magnitude of the complex value in polar form. Therefore the
magnitude of the SWR is determined by the complex reflection coefficient,
resulting in the correct value, not an approximation. The complex reflection
coefficient can be used to determine the complex impedance. SWR simply lacks
the angle of the polar information, and is thus unable to supply the
required information to determine complex impedance. Thus the value of SWR
does provide the polar magnitude of the complex reflection coefficient, not
just the |rho| value.

Gamma has an angle which can lie in any of the four quadrants.
Theoretically this cannot be neglected.

And I submit, Reg, that although the numerical value of the angle is
omitted, the effect of the angle has not been neglected.

I can't prove the approximation because I havn't the mental energy to
do the exact calculations involved.

I'm saving you the mental energy, Reg, because there are no approximations
involved--the exact calculation has been made.

For interest, my program SWRARGUE calculates the exact power lost in
the line for any SWR for a given input power of 100 watts. Power lost
is then a percentage of input power. Transmission efficiency then
follows. Note that the internal resistance of the transmitter or
conjugate matching is immaterial.

I downloaded your SWRARGUE program, Reg, and ran it. The numbers using your
program and those using my Appendix 8 are identical.

snip

The excess loss due to SWR is the difference between actual loss and
the line's overall matched attenuation, which is an input to the
program. Which, to me, appears to be an artificial way of looking at
things and your approximation arises from it.

As I said above, Reg, the values obtained using your program and those using
my Appendix 8 are identical. My method does not reveal any approximate
values, so it cannot be an artificial way of viewing the procedure.

The way to prove the point is to calculate the excess loss due to SWR
your way and compare with the results from my program.

As I just said, I have compared my results with those of your program and
the resulting numbers are identical.

I wouldn't be surprised if there's no significant difference. The
matter about the imaginary meanings of SWR and confusing reflected
power is not worth the trouble of arguing about.

Not only is there no significant difference, Reg, there is NO difference.
Think about it.

Walt, W2DU