Does not mention L networks as to why it will not give you the improper Q match
like some tuners do with a 1:1 SWR. Or did I miss that?
Think about it mathematically. With an L network you have only two
variables, the inductor and the capacitor. The goal is to transform the
impedance of the load to 50 ohms resistive. The load can be described
with just two values (at a given frequency), such as resistance and
reactance. (There are a lot of possible ways to describe the load,
whichever way you choose to use requires only two values to describe it
at a single frequency) You want to find the settings of the two
variables which solve the equation. With an L network there is exactly
one combination of those two variables that solves the equation. With a
Pi network or a T network you have three variables. With three
variables, there are an infinite number of possible combinations that
can solve the equation. All of theses solutions will result in a 50 ohm
resistive load seen by the source, yet they may also result in
unreasonable currents or voltages in the network
DE N6KB
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