Topband: Polarisation coupling effects at MF??

[LY2IJ]

Hi,

I read few remarks like this in last few months on TB reflector:

> ...
> polarisation coupling effects that have to be considered at MF.  In some
> parts of the world you won't get good coupling into the ionosphere with
> horizontal polarisation at any height.
> ...

Just curios - what is the physics/mystic behind? Different laws on 160
than 80? Distnace to ionosphere is very different?

RU1A guys use some fixed beams and don't plan to dismount them:
http://ru1a.ru/eng/about_antennas.shtml
Arkala extremes do something very wrong?

73
Arunas / LY2ij