Don't lose sight of the fact that if a linear IS linear (as opposed to only
being thought so!) tuning up at full output and then backing off the drive
just gives exactly the same gain with lower output, but lower DC to RF
efficiency. Hopefully, but not totally necessarily, lower IMD as well. Since
we aren't talking here of broadcast type service and powers, the amount of
juice out of the mains doesn't worry us too unduly.
I guess there might be something to be said for having xfmrs running about
10 degrees above ambient - it discourages condensation on them! If the
shack gets cold, then the effects of turning on the heat when you go in can
lead to condensation on items of high thermal mass - it's especially a
problem with machines such as lathes and mills, but HV xfmrs are much the
same in respect of high thermal mass.
73
Peter G3RZP
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