Terry,
I was typing faster than I was thinking yesterday.
Most commercial antenna tuners on the market
are T configuration circuits, not Pi as I typed
before! Their circuit description I gave you
is correct. In the L-circuit, the inductor is in series
with the signal path on the way to the antenna,
and the capacitor goes to ground. In the Pi
circuit, a la Nye Viking, there are two capacitors,
one on either side of the inductor. You can switch the
capacitor to either the input side or output side using
the Ten Tec tuner ( or the built in processor does in
the auto tune Ten Tec unit), I am not sure yet, but
I believe the X Match may be similar in its' basic
circuit to the Ten Tec L design, but perhaps not,
as Paul has three patents on the X Match design!
By the way, with the inductor in series with the signal
you get around 18 dB more 2nd harmonic attenuation,
and some 28 dB more 3rd harmonic suppression
than obtained with the T-circuit tuners.
Sorry again for my error yesterday, Terry.
73, Jim, AH6NB
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