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Old March 26th 05, 12:42 AM
 
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Nigel
I have little experience with dish antennas but I do know that to provide
the 'new' it is
one percent insparation and 99 percent persperation, so how about this
aproach:
Determine frequency of use.
Then draw a graph of frequency versus reactance change from a zero point
indicating resonance
of the prime frequency.
This curve is parabolic and would be an ideal starting point as there would
seem to be a connection
If one would move to far away from the point of resonance I would suggest
that the dish it's self
would rise in temperature as current starts to flow instead of a pure 'loss
less' reflective action.
Regards
Art




"Nigel M" wrote in message
...
I've been looking to make a linear parabolic reflector for Wi-Fi, I've
found quite a few sources, such as:

http://www.genericgeek.com/index.php?q=node/280

http://www.freeantennas.com/projects...te2/index.html

Those I've found all give templates for a parabola, but without any
explanation as to why they have chosen that *particular* parabola, or
the formula used to draw it. As a result, the drawings are a bit
"sketchy" to say the least!

I know radio amateurs are often knowledgeable on antennae, so I thought
this was a good place to ask. I'd like to know a bit more theory, and
the pros and cons of various parabolic shapes.


--
Nigel M
"Occam's razor is not always sharp"