Jim says:
> >I am pondering ways of actually measuring the efficiencies of these
> tuners, >but am not sure how to proceed.
>
>
measure the load impedance, measure the current with a thermo ammeter.
Calibrate the thermoammeter with DC: measure its RF resistance (not easy!)
at the frequency in question, ,measure the DC resistance and calculate a
correction factor. Taking into account the inaccuracies, and the fact that
the tuner should hopefully be 98% efficient or better, you may well find
that the measurements tell you that the tuner is really an amplifier!
Seriously, I think the best way to get an idea of tuner efficiency is
temperature rise after ten minutes of key down at full power. And if the
Delrin catches fire before then, you know it ain't that efficient..........
73
Peter G3RZP
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