Topband: A wee bit more on power coupling

Pete Smith n4zr@contesting.com
Thu, 09 May 2002 07:51:32 -0400


At 09:18 PM 5/8/02 -0700, Robert Brown wrote:
> > > 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.

Well then, I guess I share Tom's confusion.  You did state that verticals 
would be the antennas of choice in NA and EU, based on the amount of 
insertion loss for a dipole.  It seems reasonable to ask, "-24 dB compared 
to what?"  Or asking the question the other way round, what would be the 
insertion loss of a vertical at the same locations?


73, Pete N4ZR

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