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The other thing is and I hear you about the antenna tuner but doesn't a tuner match the rig to the tuner rather than the load? And while I can appreciate protecting the finals but then what does that
say for maximum power transfer? Would "you can't have your cake and eat it" be a good analogy here? Lenny

It's a dessert topping _and_ a foot ointment!

An "antenna tuner" or "transmatch" is an impedance transformer. It
works both in both directions.

In principle, you can place a suitably-tuned matching network anywhere
between the rig, and the load, and then adjust it so that the rig
"sees" the nice easy 50-ohm-resistive, no-reactance load that it's
designed to work into. Your transmitter will then deliver its
intended output power without burning up... it'll "think" it's working
into an ideal load, because that's what it sees.

Now, depending on where the matching network is (how much transmission
line is between it, and the antenna), you'll need to adjust the
matching differently in order to achieve this goal. As you move the
matching network away from the antenna, the impedance that you "see"
at that point will be transformed by the transmission line (you can
calculate this using a Smith chart). You'll need a different setting
on the matcher to transform this impedance into a friendly 50-ohm
resistive value.

Antenna tuners typically have a limited matching range. Some loads
impedances are very difficult to match - they're very high-Z, or very
low-Z, or extremely reactive. Matching them may require "difficult"
values of inductance or capacitance in the matching network. Or, it
may result in such high circulating currents in the matching network
that you waste a lot of your transmitter power in losses in the
network, or may result in such high voltages that the components "arc
over".

So, it really depends a lot on your setup.

Putting the matching network near the antenna (rather than near the
rig) does have some advantages in terms of power efficiency. With
this arrangement, the whole run of coax from the rig to the antenna is
"seeing" a 50-ohm impedance when it looks towards the antenna - the
SWR on the coax itself is 1:1 or close to it. If the tuner is near
the rig, then even if you tune it so that the rig sees 1:1, you've
still got a high SWR on the coax all the way out to the antenna... and
this can result in high currents at low-impedance points (losses) and
high voltages at high-impedance points (the coax itself could arc over
at high power).

For mobile antennas, a fairly common approach is to add a switchable
"base loading coil" very close to the base of the antenna... a coil or
toroid with multiple taps and a switch is often used. In the
frequencies around the one the antenna is tuned for, the _resistive_
part of the antenna impedance often doesn't change very much, but the
_reactive_ part changes rapidly on either side of resonance. If you
tune the antenna so that the reactance is near zero at the high end of
the band, and becomes capacitive as you move down the band to lower
frequencies, you can use a switchable inductor (at the antenna base)
to cancel out this capacitance and restore a (near-)resonant
condition. I gather that a lot of people have done this and been
happy with the results.