"Yuri Blanarovich" wrote in
:

....
I realized that Yagi has low impedance and I generally do not like any
matching and introducing unnecessary loses. The way for maximum gain,
clean pattern, great F/B, 50 ohm feedpoint impedance and no matching
gizmos to me was to go Quad and Quad/Yagi element combinations. Quads
have higher impedance and by adding elements, the impedance would drop
to around 50 ohms.

Yuri, that is your approach, but it is not the only one.

Others of us quantify the expected transformation losses, and add them into
the gain equation to deal with the effects, making a design selection on a
rational basis rather that just excluding a whole bunch of solutions
because of a prejudice about matching loss.

Owen