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Old January 5th 05, 06:35 PM
Richard Clark
 
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On Tue, 4 Jan 2005 14:53:35 -0400, "redrum" ninguna wrote:

Which is better?

is scantenna really omnidirectional? is it built for a better reception on
the most used frequencies or is really multiband?

who sells the better implementation of discone?

my needs on scanning are 25Mhz to 1.3 Ghz.

I own a uniden bc-796d and a bc-246t

Thanks for any help.

Greetings from Chile!


Hello OM,

There are many omnidirectional designs. There are many multi band
designs. There are very few that accomplish both successfully for a
wide variety of signals over a wide variety of frequencies.

Wide band antennas like a Discone are really only useful over roughly
2 or 3 octaves (doublings of the base frequency). They are often
specified by impedance match; and as correct as this specification is,
it is not complete. You also need to consider the angles that it is
most sensitive to. For the first 2 or 3 octaves, this would be toward
the horizon. For the 4th and higher octaves, the most sensitive
regions for listening begin to climb higher into the sky. Who do you
want to listen to? Where are they? This is the meaningful relation
you should seek to optimize.

73's
Richard Clark, KB7QHC