K8CC added:
> >Remember, a rotary doublet (as in a non-reasonant dipole) will show
> >good nulls off the ends. The direction(s) null(s) is/are seen off the
> >sides & back of a beam can be even more helpful than where the
> >signal peaks from.
>
>I'd point out that not all beams have nulls directly off the back. Many
>yagi designs have a lobe straight off the back with nulls somewhat off the
>main axis.
>
>Before you start trying to DF off of nulls, you'd better figure out where
>the nulls are.
>
>In that regard a rotary dipole is the most certain tool, because you know
>there are only two nulls, and they're obvious!
Roger that, Dave!
Peaks are rather broad, but knowing what is being used & where
the nulls are being seen, something more accurate might be able
to be figured out.
It was nulls off the back & rear quarters of a quad that concluded our
chase for the 12m sea surface radar in mainland China - might not
be able to do this by remote so well as in person, but with care it
can be made to work.
73, VR2BrettGraham
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