[BC] 1/2 wave spacing for 3 horizontal bays possible?

[Rob Landry]

On Wed, 22 Feb 2012, wpio fm 89.3 wrote:

> The followup question: is horizontal-only a LOT worse than 
> vertical-only?  I tend to think not because 1) I've read that the 
> polarity doesn't hold its orientation anyway as it traverses the 
> surface, and 2) car antennas are very ofter NOT vertical structures.  I 
> see a lot of short slanted ones on cars these days.

I don't like horizontal polarization. The stations I've known that have 
used it have had multipath problems that largely went away when the 
stations went circular.

The bulk of our listeners are getting more or less randomly polarized 
signals because they are bouncing off various terrain features and other 
objects. In a moving vehicle, the antenna is getting signals whose 
polarization is not only random but constantly changing. Picket-fencing 
occurs as the antenna moves from points where the signal accords with its 
polarization to points where it is opposite; but if the transmitted signal 
is circularly or eliptically polarized, there will always be some signal 
that accords with the vehicle antenna's orientation, so picket-fencing is 
less than it would be with a signal transmitted with horizontal or 
vertical polarization.

I would therefore not use anything but circular polarization except as a 
last resort.

Rob