On Fri, 20 Apr 2007 12:46:50 -0700, Roy Lewallen
wrote:

But I'm claiming you can't get directivity such that you can favor one
radiator over the other, by any antenna lying entirely in the null
space. In other words, any antenna you build in that null space will
detect zero field.

Hi Roy,

No dispute there either.

The special thing about null space is simply that
it's a limit, and it makes a good vehicle for illustration because we
can more easily distinguish between nothing and something than between
two different levels.

That is distinctive as being binary, certainly; but I am sure there is
something between two different levels that are distinguishable to the
same degree. The difference between 0 and 1 is no greater than
between 1 and 2.

However, if we open up the meaning of null to mean a point, or region,
within which we find a minimum due to the combination of all wave
contributions, then I would say a directive antenna is back in the
game, and that it exhibits Owens proposition (if I understand it - but
I still need to see Owen's elaboration).

I'll extend my hypothesis to include all such regions. Create a null
space or region of any size or shape by superposing any number of waves.

But this says nothing of the quality of "null" as I extended it above
which could be supported by a directional antenna. As I am still
unsure of the nature of Owen's proposition, I will leave the quality
of "null" for Owen to discuss or discard.

73's
Richard Clark, KB7QHC