Building the Double BiQuad

I don't know the real name for this antenna, but it is two BiQuads end on end. It also seems to be an extremely forgiving design. I made quite a mess of the construction and I'm getting 12dBi gain. I did think I was getting none, but discovered that the antenna is horizontally polarized when held vertically.

Free Space
Side Lengthmm
Offset from reflectormm
Reflector heightmm (Minimum)
Reflector Widthmm (Minimum)
The size of the reflector and its distance from the active element affect the feed impedance. The ARRL handbook says there should be a 1/4 wavelength edge beyond the active element.

Misc Notes

From the front.
From the Back
Looking down on it when it is aligned for vertical polarization (i.e. the diamonds are horizontal)