David wrote:
>> What pattern are you looking for?  In the plane of the board?
>> Perpendicular to the board?  Something else?
>
> ... the board will be at 90 degrees with respect to the "floor".

But what radiation pattern are you looking for?  In the plane of the board?
Perpendicular to the board?  Something else?

Now that you've described the orientation of the board, you could also tell
us what radiation pattern you would like from this gizmo mounted on the
wall.  In any case, please answer the questions asked.  Supplying additiona=
l
information is fine, but it's frustrating to help when you won't provide
information specifically asked about.

> Perpendicular to the ground plane, radiation for antenna such as a
> whip or helical will be away from the ground plane.

"Away" from the ground plane is rather ambiguous here.  Please be more
careful.  If you mean perpendicular to the ground plane on the antenna side=
,
then that's incorrect.  Antennas that rely on a ground plane generally
radiate parallel to the ground plane, but only in the half-space of the
antenna side.  There will be some spill to the other half-space,
particularly when the ground plane is only a wavelenth or less in extent.

> Parallel to the ground plane, radiation will be away from the board
> edge and quite directional.

There you go again.  You really can't discuss this stuff while being sloppy
with words and descriptions.  Parallel to the ground plane is clear enough,
but then you suddenly bring the board into it without specifying how that i=
s
oriented with respsect to this ground plane or the antenna.  Duh.

> My assumption is that the whole board
> must therefore be oriented at least approximately in the correct
> direction.

This is getting rediculous.  How are we supposed to know what aspect of the
"board" you consider its direction.  The plane?  Perpendicular to a face?
And how is all this oriented with respect to the antenna and its ground
plane, if your antenna even uses a ground plane?

If the board is mounted vertically (parallel to a building wall) and you
want to radiate horizontally (to every place on the same floor of the
building), then it won't help to try to make a ground plane of part of the
board.  Probably the best choice is a self-contained (not relying on ground
plane) whip oriented vertically extending above or below the board.  It
would have to contain some reactive elements to achieve resonance or the
desired impedence at substantially shorter than 1/2 wavelength.


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