In article ,
amdx wrote:

Thank you for that clear explanation.

Quite welcome!

And regarding the distance from ground-plane, I've seen two different
specs one 30.5mm and the other 18mm.

I believe that those two distances are optimizing for different things.

If I recall correctly, the 30.5 mm spacing is optimizing the antenna
for gain (the sharpest forward-looking lobe, likely).

The narrower spacing seems to optimize the design for the best
impedance match (the biquad is very close to 50 ohms in this version).

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
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