On Thu, 10 Feb 2005 03:49:58 GMT, Rick Frazier
wrote:
I'm thinking I can set the angle of radiation for a horizontal dipole,
by hanging it the proper distance above (and or towards or away from the
desired direction) to essentially add to the desired angle of radiation,
if only by some small amount.
Hi Rick,
This is true, but probably not for the reasons you may have
envisioned. Simply put, the metal acts as a shield to prevent loss to
ground. What is not lost is radiated in other directions. It aids in
those directions straight up, but it also aids in directions at every
other angle too - net result: better signal; how much: nothing
dramatic. This simple fact will probably get you more initial gain
than you will add doing anything further (short of building a tower
and putting up a beam).
Is there an optimum angle of radiation for DX,
Yes - you may hit it poorly tho'.
Though optimizing the location of the dipole for a particular angle of
radiation seems good, there will also be a corresponding cancellation of
signals at other (calculable) angles of radiation, right?
Odds are that given this vague description, that, yes, anything could
happen. Guessing your intent, well you are already in illusionland
with optimization - unless, of course, 1dB optimizations light up the
stars in your firmament.
Is it all for naught anyway? Given the action of a wire reflector, will
the sheet metal slab only look like a larger version and only in the
general direction perpendicular to the center of the sheet metal axis?
Practical answer is no one will probably notice even if you could
shift everything around to suit your best guess. You have far more
dramatic opportunities (more than 1dB) with a vertical within sight of
the ocean.
73's
Richard Clark, KB7QHC
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