Tom says:
>I'm amazed so many people buy tuners instead of building them, or
>using stubs.
Here we definitely agree. Starting from the R + jX you need to match, a
dedicated tuner can be designed to have the lowest operating Q for a particular
impedance transformation ratio.
>but moving the balun to the input of the tuner does NOT help balance
Just how well balanced are the loads anyway? I suspect that generally, probably
to around 10% mismatch isn't uncommon.. i.e. the impedances from each side to
ground don't match by 10% or possibly more.
>Tuners are probably one of the most difficult pieces of gear to
>engineer, because the frequency and impedance ranges are so
>wide.
This is because the commercial tuner has to be an egg laying, milk and wool
producing flying pig that swims. Much simplification is achieved by building a
dedicated network.
73
Peter G3RZP
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