[Moon-net] Orthogonal polarization???

[Bill Dzurilla]

Thanks to all who replied publicly and privately to my
question.  Several people said that orthogonal
polarization could be obtained by feeding one of the
yagis out of phase, but others pointed out that this
just produces circular polarization, which is not what
we want for eme.

Orthogonal polarization is supposed to be linear
polarization at 45 degrees between horizontal and
vertical.  This is supposed to be possible with the M2
XP antennas, but I called M2 and could not get a clear
explanation how to accomplish this.

As for the "exceeds 6-dB stacking gain" claim, I think
they don't really mean "stacking gain."  My guess is
they were trying to say that due to the XP's ability
to send and receive at the correct polarity, the
antenna is effectively more than 6 db better than a
horizontal only array.

73, Bill NZ5N 
--- graham <graham.d at orange.fr> wrote:

> 
> >.  I do not know how
> >one exceeds 6-dB stacking gain
> 
> There are a number of antennas that display this
> characteristic during 
> array modelling.....whether they actually realise
> the result in the real 
> world would be difficult/impossible to verify on an
> amateur range.
> 
> It happens 'typically' in some older designs that
> were not computer 
> optimised, the old Tonna 16/17 can be easily made to
> display this if anyone 
> wants to play with it..... I forget the stacking
> parameters that give 
> this > 6dB result.
> 
> It occurs because coupling of the antennas together
> in an array has 
> influence on  each part of the array.
> 
> But one has to be careful because poor segmentation
> can also distort 
> results, either way,  as can 'short cut' modellers (
> such as YO)  and the 
> most popular g/t  modeller ( yagi 3.54) which has a
> 3dB 'assumed' gain in 
> one plane also....
> 
> Graham F5VHX
> 
> 
> 
> _______________________________________________
> Moon-Net posting and subscription instructions are
> at http://www.nlsa.com/nets/moon-net-help.html
> 
> 



      ____________________________________________________________________________________
Be a better friend, newshound, and 
know-it-all with Yahoo! Mobile.  Try it now.  http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ