Leaving aside the comments on bread (you haven't tried UK sliced white bread for
yukkiness!), my experience is that if you design the tuner for the antenna,
there are few situations where problems occur.
The usual T network and 'ultimate transmatch' circuits have problems with the
working Q getting too high. L networks have a working Q fixed by the
transformation ratio. It's only in the case of a high impedance antenna, such as
a long wire or certain lengths of a shunt fed unipole, that the voltage should
get so high even at 1500 watts, as to be that much of a problem. My parallel
tuned, link coupled tuner only has about 600 volts across the open wire feeder
terminals at 400 watts: that's 1200 volts at 1600 watts, which isn't that high.
That's feeding an 80m dipole (approximately - cut to fit between supports, not
to frequency) through about 60 feet of open wire line.
You can build a tuner and buy a lot of beer (or good bread!) for the cost of one
of these commercial boxes.
73
Peter G3RZP
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