On 12/17/2012 1:04 PM, Jim Nichols wrote:
> ...
> I stopped to take a look at the new Civil Air Patrol Mobile Unit, used for
> searches for downed aircraft. I was impressed by the communications antennae:
> http://gallery.leica-users.org/v/OldNick/59+edit.jpg.html
Unless fundamental principles have changed, that antenna looks like a poor
design.
Antennas needs a ground plane for maximum efficiency. In this case, the ground
plane is the vehicle. By placing the
antenna off one corner, you get a highly asymmetric sensitivity pattern, high
to the right front and low to the left rear.
OTOH, hiding about a third of the length behind the van for about a third of
directions should negatively affect
sensitivity.
I wonder what frequency it is for. If the whole thing is antenna, it's quite
long wave. If not, and the small things
along its length are tuning coils, rather than connectors for sections, roof
antenna(s), perhaps hinged, should be more
electronically effective.
Antennae Head Moose
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What if the Hokey Pokey *IS* what it's all about?
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