If the radiation at 3 degrees is -8.9 dB relative to the maximum amplitude
we can still work DX.
Dave WX7G
On May 8, 2012 9:18 AM, "Richard Fry" <rfry@adams.net> wrote:
> Dave WX7G wrote:
>
> >The program W6ELProp gives the take-off-angle needed for any path. Looking
> >at 80 meter paths (it does 801-0 meters) the angles for DX paths are in
> the
> >range of 3-15 degrees.
>
> Assuming those angles are true for DX paths, note that if the NEC far-field
> elevation pattern for a 1/4-wave monopole was the only radiation leaving
> the
> antenna, the field at 3 degrees elevation would be about 8.9 dB below the
> field at the center of the so called take-off angle (see link below - note
> Photobucket stripped the decimal from the 3.9MHz link).
>
> The surface wave really needs to be recognized in such evaluations.
>
> http://i62.photobucket.com/albums/h85/rfry-100/39MHz_Elepat_6_mS.jpg
>
>
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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