On Sat, 4 Jun 2011 19:38:55 -0700 (PDT), Michael
wrote:

I just remembered most of those external baluns are 1:1 baluns. I do
have one external commercial 4:1 balun, and one 4:1 balun I hand wound
from a schematic in one of my antenna books.

Hi Michael,

The odds are that the BalUns you wound are similar to the ones in your
tuner(s) - and they will NOT do the job properly.

By properly, the BalUn MUST choke the line. This comes for free with
the W2DU style, as there is only one way to build one, the right way.

The distinction is between what are called voltage BalUns and current
BalUns. Frequently, web sites that purport to know the difference
DON'T know the difference. The W2DU BalUn is an example of a current
BalUn with a 1:1 ratio. It is also a choke. Very few BalUns that are
published on the web are current BalUns. Similarly, very few have the
necessary choking action.

One solution is to feed a W2DU BalUn, that in turn feeds any BalUn
with the required transformation ratio, that then in turn feeds the
antenna. The W2DU BalUn takes care of the proper choking action
needed. However, this may not work with the internal BalUns found in
nearly every tuner on the market. (How does one insert the choke to
an internal BalUn?) Problem here is that if there is ANY path to
ground that goes around the choke, you have just made it an exercise
in futility.

And lastly, you have described a number of problems with the antenna
that were both inside and outside of the focus of gain. ALL were
functions of Common Mode currents. Choking the line is the best
all-around solution.

73's
Richard Clark, KB7QHC