On 7/9/2015 3:50 PM, Ralph Mowery wrote:
"rickman" wrote in message
...
The magnitude DEPENDS on the frequency dependant parts.


But the ratio of Vmax/Vmin does not.

Huh? I'm pretty sure the VSWR is a function of frequency. A great deal
about the impedances *and* the voltages change with frequency.
--

Rick

The SWR is measured at a fixed frequency , so the formular is frequency
independant. Each time you change frequencies , the SWR will usually
change.

I think that is the definition of "frequency dependent".


I guess that it all depends on how you look at it. You can use a sweep
generator and spectrum analizer to get a SWR curve over a frequency range.
If you feed a dummy load of pure resistance, it will not mater what
frequency you use, the swr will stay the same. If the load has an
impedance that is not constant at all frequencies, then the swr will change
as the frequency changes.

I'm not going to debate the fine details of the subject. Anyone can
believe anything they wish. But the bottom line is that the SWR depends
on the components used in the system which, in any useful SWR
measurement, will give you a frequency dependent value.

The SWR using a dummy (purely resistive) load will not depend on
frequency, but it also won't tell you a thing about your antenna system.

--

Rick