I need to add a clarifier to this post.
If the phases and and magnitudes of the paired elements
are exactly the same, then radiation to the rear is zero.
In the real world this is difficult if not impossible to do.
It certainly cannot be done with a yagi unless possibly,
when elements are contorted to ensure pure resistance
feed at the appropiate frequency
However, what is possible with a alternate design is to
have maximum front to back at max gain when the max
gain is constant over a range of frequencies such that
the max front to back which is usually a peak,
can appear at a point where the gain is still at a
maximum.

Regards
Art .........KB9MZ



" wrote in message
news:dySVd.30807$r55.174@attbi_s52...
I have just come to realise that if one drew a polygon of element phases in
a array
and all elements were 180 degrees to its companion element and excluding
the
driven element, the max gain and max front to back will occur at the SAME
frequency!
Until now I was of the understanding that these two max figures could not
occur at
the same frequency. Is there anything written about this possibility?
Regards
Art