"Reg Edwards" wrote in message
...
What all you experts have forgotten is that SWR on a
lossless line is the ratio of two voltages, max and
min, SPACED APART BY 1/4-WAVELENGTH. That is if the
line is long enough to contain both a max and a min.

When the line is not lossless, ie., it has appreciable
attenuation in dB per 1/4-wavelength, then the ratio is
'distorted' and has a phase angle. So negative values
of indicated SWR can be expected at some values of |
Vmax | / | Vmin |

SWR is calculated from the square of | rho |. As

VSWR is defined as |Vmax|/|Vmin| and so can never be negative. in lossless
lines this expression can be reduced to a function of rho, but that method
is not valid in lossy lines. VSWR is not a constant in lossy lines and
probably doesn't really mean much of anything as each voltage maximum and
minimum is a different value, so which ones do you use???

VSWR is not a constant in lossy lines and
probably doesn't really mean much of anything as each
voltage maximum and
minimum is a different value, so which ones do you
use???

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Dear David,

You have expressed my sentiments exactly. I have never
used either or any of them. What does anybody do with
value of SWR when they imagine they know it? I'm
pleased to make your acquaintance!

For some years I have mildly advertised the idea of
changing the name the name of the common-or-garden, so
called SWR meter / combined forward-and-reflected power
meter, to the TLI (Transmitter Loading Indicator) which
is all it does. Although I must admit, at the present
state of the art, it is a very useful instrument when
changing antennas.

Is the transmitter loaded with a resistance of 50 ohms
or is it not?

{ Actually, the meter on my top-band transmitter
indicates relative to 75 ohms }

And there HAS to be SOMETHING more than the weather to
talk about in QSO's and, of course, on this newsgroup.
;o)
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Reg, G4FGQ