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Old January 4th 04, 01:42 AM
Art Unwin KB9MZ
 
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Let me clarify this statement so that we are on the same page.
I was hearing several conversations going on the same frequency. Those
conversing obviously were oblivious to other users on the frequency because
of propergation or the peculiarities of my antenna.
I refrained from entering into conversation with the local group because by
joining one group would have caused problems for other groups on the same
frequency.
On reflection it would appear that the horizontal dipole gave low angle TOA
all the way thru 90 degrees.
Thus this is inferior to a vertical that captures the low angles and
descriminates against the high angles plus inferior to a poor vertical that
discriminates against low angles.
This just shows how much ground effect controls the
verticals but only to a much lower extent on horizontally polarised signals
with respect to selectivity.With respect to noise it does not affect me to
much in the comparison because of the use of a Faraday shield.
Regards
Art
"Art Unwin KB9MZ" wrote in message
m...
"Reg Edwards" wrote in message

...
Incoming radiation angles can be obtained by geometric calculation.
Pythagorus and all that, taking earth curvature, height of ionospheric
layers, number of hops, etc, etc, into account.


Then point your receiving beam into it, if it is adjustable in the

vertical
plane. Very non-critical. Antenna apperture angles in the vertical

plane
are extremely broad.


The stuff often comes in from more than one angle. Interference between

the
different paths causes fading and distortion. An antenna will collect

from
all vertical angles regardles of elevation.
----
Reg

===================




Interesting thing happened with the antenna last night.
Had the antenna in the vertical position close to ground ( it is a
truncated co linear dipole) And was prevented from joining the local
group because of multiple QSOs on the same frequency!

Art