"AF6AY" wrote

Lots of good stuff snipped....

Now ANY impedance-matching tuner will let one load up just
about anything. All that serves is to transfer the most RF power
into a load. What is NOT known is WHERE all that RF is going.
Unless some ham has a balloon-borne sensor and data transfer
gizmo, NOBODY can know just where the pattern is going to be.
Big trees WILL affect the pattern, especially changing it between
dry and wet climate times and between different kinds of trees.
So will structures and assorted conductive things (aluminum
patio covers, small garden sheds, power, phone, and TV cables)
all within the near-field (within five or so wavelengths). Even
some houses which have had aluminum siding added on
compared to similar houses with just wood or stucco or brick
siding.


Everyone's residential location varies greatly and only a very
few are "perfect" (as to the antenna analyzer programs). One
can load up practically anything with a tuner but only the shape
and arrangement of conductive elements is going to determine
where most of the RF goes to (or comes from). No tuner can
help that.

I had to leave the important stuff... sorry to make everyone scroll down....
Len, I'm confused as to just what you're specifically referring to. Do you
mean a doublet fed with balanced line (300 or 450 ohm window line) to a
transmatch in the shack is something you don't recommend? Or are you
referring to this system fed with coax to an autotuner? It'd seem to me
that, as long as the system (fed with window line to keep the serious losses
down to negligible) is in the clear, the transmission line is 90 degrees to
the doublet for the "required" distance... all should be fine and the
radiation pattern should emanate properly from the antenna itself, not so
much the transmission line. ?

Howard N7SO