For horizontal polarization, picture a rectangular driven element with
the narrow end down. It is about .1274 wavelengths at the bottom and
top. It is about .40266 wavelengths tall. It is fed at the center of the
bottom wire.

Put a reflector behind it. The reflector is .2643 wavelengths at the
bottom and top. It is .305 wavelengths high.

The geometric center of the reflector aligns with the geometric center
of the driven element.

The feed impedance is about 48+j0 ohms but can be adjusted based on
other requirements, if necessary. The max gain is 12.9dBi when about 3
wavelengths above earth. I can reduce the wavelengths above earth with
an attendant increase in max radiation angle, but that's another study.

I might use this one on 434MHz for a 1000ft link. I don't really need
the gain so much as the matching and the desire to minimize radiation in
useless directions as well as max signal at a low angle.

Thoughts?