Rich said:
>i have yet to see a tuner that did not achive a match when adjusted
>with a reflectometer.
That an input match can be achieved is not in dispute.
When the input match is achieved, there should be output, and with some tuner
circuits, that may not always be the case. In other words, two match positions
can be obtained - one that gives output, and the other that 'matches' the
internal losses. An example has already been given.
Simpler circuits, such as balanced L networks fed from a suitable balun, are
less likely to suffer from this. Link coupled tuned circuits are fairly immune,
too, although if they happen to feeding a line length such that the impedance is
very high or very low, some problems can occur, with either Marconi effect or
leakage inductance in the coupling.
Any network where you can get matching with various values of working Q can give
problems, too, as Tom and Barry have indicated. If you spit at the the coil and
it's so hot it spits back, you have the tuner maladjusted!
73
Peter G3RZP
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