Topband: A wee bit more on power coupling

[Robert Brown]

On Wed, 8 May 2002, Tom Rauch wrote:

> > For horizontal dipoles oriented E-W, power coupling in North
> > America and Europe is still very unfavorable to the north, as
> > shown below for central locations in those continents:
> > 
> >                     W0        DL
> >                    (dB)      (dB)
> > 
> >             N     -24.0     -24.0
> >            E-W     -6.6      -5.3
> >             S      -4.7      -4.1
> > 
> > So verticals would be the antenna of choice in NA and EU.
> 
> Are you saying the signal from a horizontal dipole at my location 
> oriented E-W (broadside N/S) would be 24 dB down due north of me into 
> Ohio or Ontario compared to a vertically polarized signal with the 
> same ERP?

Tom, 

No, that is not what I said nor meant; there was no mention of a
vertically polarized signal with the same ERP. 


The -24 dB insertion loss or power coupling is the result of a
horizontally polarized signal from a dipole encountering steep geomagnetic
field lines. It is the dipole's signal that is attenuated.  No other
antenna or polarization is involved in the calculation and I am at a loss
as to how you brought one into the discussion as I made no mention of one
in that section of my remarks.

73,

Bob, NM7M