On Fri, 28 Sep 2001, Nate Carlson wrote:

> Kind of new to the antenna stuff -- anyone have any good links /
> references / etc that explains the differences between types of antennas?

First of all, I recommend anyone doing any sort of wireless to get your
ham license or at least browse the material.  Start at www.qrz.com for
good info.  Lots of EE's hang out on the bulletin boards and stuff too.

> I mean, I know that yagi's generally have a wider beam than parabolics,
> etc, but that's all gleaned from product specifications, not actual
> information about the antenna.

Yagi has a wider beam and generally higher gain.  Good for hams, bad for
keeping your wireless net private.
 
> But, for a specific question: what's the difference between vertical and
> horizontal polarity on a parabolic?

With a parbolic your antenna (I don't know your exact design) is is either
a dish or a curved piece of rectangular material.  The driven element (the
thingie in the center) is usually a piece of metal that's
oblong (copper pipe works well).  Vertical polarization is if the driven
element is higher than it is wide, horizontal is if it's wider than it is
high.  There is also circular polarization, which you can use if you have
a round coil as the driven element.  Basically for max performance, all
your antennas should be polarized identically.  The most common is
vertical since it takes up less "real estate".

-Brian