Ive copied US BCB stations as far inland as Chicago in the far eastern
Meditaranean. Id be curious what the propagation mode was and if sky wave
how many hops?
I also regularly hear the LF BCB stations from EU and AF in the roughly
150-200KHz region and sometimes sounding like locals. What path is this?
I dont believe that the antipodes or other very long haul 160M QSO's have
completely been explained yet BUT Ive had better luck with an inverted vee
than phased full size 1/4 wave verticals with 32 elevated radials for
each.at grayline.
OTOH at other times the verticals are FAR superior.
Carl
KM1H
Carl
KM1H
----- Original Message -----
From: "Richard Fry" <rfry@adams.net>
To: <topband@contesting.com>
Sent: Saturday, May 05, 2012 3:51 PM
Subject: Re: Topband: Fwd: radals fer 160m vertcal
> RE:
>>> Those fields from very low elevation angles (say, less then 5 degrees)
>>> can reach the ionosphere, and under the right conditions return to the
>>> earth as a useful skywave.
>
> Mike Waters asks:
>>My question is, on what amateur bands is this common? And on what
>>amateur bands is this possible?
>
> It is universally common for the highest radiated fields launched by
> vertical monopoles to occur in the elevation sector between the horizontal
> plane and 5 degrees above the horizontal plane. This is a natural
> consequence of the summation of individual fields generated along the
> height
> of the monopole by the r-f current flow there.
>
> The graphic linked below is taken from Radio Engineers' Handbook by F. E.
> Terman (1st Ed), showing that the skywave from the monopole of a typical
> AM
> broadcast station that serves the greatest single-hop range leaves the
> radiator at elevation angles of 5 degrees and less.
>
> This will be true for HF monopoles, also, but the range would depend on
> the
> height of the layer of the ionosphere where the reflection takes place.
>
> http://i62.photobucket.com/albums/h85/rfry-100/TermanFig55.jpg
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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