The only "inconsistency" is that an SWR meter is obviously NOT a "TLI",
or transmitter loading indicator, as you've been so kind as to
graphically point out.
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It would be more true if you had said the SWR meter is not being used as an
SWR meter because there's no SWR for it to measure.
There's an inconsistency because the line between transmitter and meter is
not 50 ohms. The Tx is incorrectly loaded but neither meter scale gives any
indication of it to the user. It could be a serious matter but there's no
warning. The operator is allowed to believe he has set up the equipment
correctly.
A TLI suffers from the same disadvantage as an SWR meter - it gives the
correct answers only when making measurements on 50-ohm lines. This should
not be surprising. They have identical circuits.
But when there is no line of any impedance, just a few inches of wire, the
TLI indicates correctly. Whereas the SWR meter requires at least a
1/4-wavelength of 50-ohm line before it stops being dishonest. And it
doesn't stop telling white lies even on longer lengths.
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