>From mid-November through mid-February, daylight over Antarctica
and the Southern Ocean prevents the 160 meter long path from
propagating due south (+/- about 20 degrees).
Except for sunspot minimum, short path propagation transiting only
the northern hemisphere to southeast Asia is very uncommon from the
eastern USA.
160 and 80 meter propagation from eastern USA to southeast Asia is
most likely to follow the SSE evening and SSW sunrise gray lines,
although as Tom says, its best to listen for the actual path.
>From 1145-1300Z (the likely times for long path propagation to southeast
Asia during eastern USA morning) the gray line passes approximately
through HC8, so the long path is likely to be SSW or possibly SW
Because the southern magnetic pole is just off the coast of Antarctica and
directly south of Australia, the SSW long path crosses through the auroral
belt and this long path is significantly affected by geomagnetic activity.
>From 2300-2330Z (the most likely times for southeast Asia long path in
eastern USA evening) the grey line crosses Uruguay, so the long path to
southeast Asia is likely to be SSE or possibly SE. Because the southern
magnetic pole is on the opposite side of Antarctica, the SSE long path is
much less affected by geomagnetic conditions than the 1145-1300Z SSW
long path.
73
Frank
W3LPL
----- Original Message -----
From: "Tom W8JI" <w8ji@w8ji.com>
To: "Steven R Daniel, D.D.S." <nn4t@comcast.net>, topband@contesting.com
Sent: Tuesday, January 27, 2015 7:21:00 PM
Subject: Re: Topband: K levels and skew path on 160
>I was rereading the article by Cary Oler and Ted Cohen (N4XX), published in
> 1998, which provided a good primer for understanding, as much as we can,
> propagation on Topband. In one section the impact of a high K index on the
> auroral oval, and its subsequent impact on signals passing through the
> oval,
> was discussed. My question is does the K index, especially at higher
> levels,
> impact the SW or SSW skew path many of us were trying to use this morning
> to
> work Ken, XW4ZW? Any information or observations will be appreciated.
> Best,
Steve,
>From my location now, and when I was in Ohio, it was quite normal for any
signal passing near or through the north magnetic pole to never make it
through via the direct path. When signals were heard, they were always
skewed in some other direction.
The only exception seems to be when sunspots and geomagnetic activity are
very low. In this very last solar minimum, when sunspots were absent, many
stations would appear via north. Of course that gave the northern NA
stations nearly north of me a clear advantage, because they were closer.
My policy is to not worry about predicting or expecting anything, and I
rarely even look at solar activity. I just listen in all dark directions
when the station is almost on the opposite side of the world, especially
when he is anywhere near the equator and far,far, away. :)
73 Tom
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