The cheapest route (depending on what you're doing) is to build one. Yes -
real ham radio - make something!!!
If you want a tuner to match anything when you take it out portable, you
have different requirements than if you want one for home. For a fixed
installation, it's easier to measure the impedance roughly and build a
suitable network - and it is one of hell of a lot cheaper. Frequently, it is
also more efficient, which means less problems with arcs, sparks and fires.
If you can use a network which has a lower working Q, the efficiency goes
up, as does the bandwidth.
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