The L network tuner can match any load to any source impedance provided the
L and C are reactances are large and small enough to match at extreme values
(either very low or very high load impedances). It is possible to connect
the L and C in four possible ways. Any source impedance and any load
impedance can always be matched with two of the four possible
configurations. One configuration will be a low pass filter while the other
will be a high pass.
Usually, the L network tuner will provide the least loss compared to the Pi
or Tee configurations.
Under some circumstances, all four configurations will provide a match...two
will be low pass and the other two will be high pass configurations. In
either case, it behooves the operator to determine which configuration ( out
of the two or four possibles ) will provide the least loss...usually the one
with the lowest value of inductance. If it turns out that this is a high
pass configuration and you want harmonic suppression in the tuner, use a 2
to 30 mhz low pass filter in the coax line between rig and tuner...which is
probably not a bad idea with any tuner.
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