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Walter Maxwell · April 5th 07, 11:22 PM posted to rec.radio.amateur.antenna

On Thu, 05 Apr 2007 18:05:02 GMT, wrote:

Walter Maxwell wrote:
On 5 Apr 2007 10:05:43 -0700, "art" wrote:

On 26 Mar, 21:49, (Richard Harrison) wrote:
Art wrote:

"Any thoughts as to why it sgould be so and the scientific facts to
support it?"

We have plumb lines and bubble levels which allow easy determination of
vertical and horizontal directions.

We often inhabit a nearly horizontal plane

If we are as likely as not to communicate with any particular direction,
an omidirectional vertical antenna makes sense. An inclined wire would
favor some direction to the detriment of another. Sure a slopimg wire
works but doesn`t reach maximum height or length as effectively as a
vertical or horizontal wire would.

Why a straight dipole and not a V-shaped element? The V-shape corrupts
the nulls at the ends of the straight wire.

Vertical and horizontal antennas are not solely accidents of history.

Best regards, Richard Harrison, KB5WZI

Richard,
It is well known that near maximum "overall" polarity gain can be
obtained by placing a vertical at right angles with respect to earth.
Now -a -days maximum gain is required of a certain polarity which
requires a specific accuracy of less than 1 degree . So yes, in your
working years straight up is good enough but these days of WiFi and
all that concentration is applied for purity of polarity which
requires a resonance at around 3 degrees to the vertical. This can be
determined arithematically according to known laws. Ofcourse as one
moves higher this offset angle changes. This same phenomina or tilt
angle applies for all polarities where maximum gain is required for
purity of polarization.The days have gone where just putting up a wire
satisfies all.
Regards
Art

Educate me, Art, what is 'polarity' gain?

That's when you go to a Polish wedding and put on weight from eating
kielbasa.

This is related to the "purity of polarization" which is a measure
of the quality of the kielbasa served and the Polish music played
at the wedding.

Now that is what I can understand, Joe.

Walt