A quad driven element is like a vertical stack of two
bent dipoles. It can easily be determined from your
favorite NEC program that the "stacking gain" is about
1.25 dB for the 1/4 wavelength stacking distance.
A quad type beam is like a vertical stack of two yagis,
with bent elements. The fallacy you sometimes read
about is the idea that the stacking gain in the multi-element
case is the same 1.25 dB as for the dipoles. However,
stacking doesn't work that way. As the quad boom gets
longer, the stacking gain decreases. A "monster" quad
will have negligible stacking gain and be no better than
a Yagi with the same element spacing on the same boom.
Maybe that it why you don't see > 7 element designs.
Rick N6RK
On 8/29/2016 4:52 PM, Courtney Judd wrote:
I have been thinking about building a monster quad for 6 mtrs. I have
googled quads and all about but came up with very little data to work
with. I did find a 7 el regular spaced quad on 19 ft boom but I was
thinking of more elements and wide spaced... I have several 44 ft 2 in
Thanks, Cort K4WI
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