Topband: RE: skewed paths

[Bill Tippett]

(Note to all...this is also a test of Mailman...the admin interface
apparently truncates long messages even though they are actually intact so
it was my mistake to think there was a problem.  Please resubmit any
messges that did not make it the first time...assuming this one is not
truncated)

N0FP wrote:

>I am personally quite interested in back scatter since this may be the only
way I will ever be able to communicate with our 160 comrades in EU from the
dark recesses of Minnesota.

        Don't be too pessimistic Ford...some of your MN neighbors have the 
following DXCC totals ( http://www.qsl.net/160/ )

N0TB  206
W0BV  190
N0AT  186

...and 5 of the top European totals are Scandinavians who are much farther
north than you are.

        Regarding the skew discussion, I believe there are (at least) two 
different phenomena at work which are being intermingled in the discussion:

1.  Skew (usually < 90 degrees from true) away from the magnetic poles when
the great circle path path goes through the Auroral Zone (N or S) AND when
the geomagnetic field (WWV) is Kp > 2.  A typical example is EU signals
being skewed southward during a disturbance...the amount depends roughly
on the magnitude of the disturbance.  The greatest geomagnetic skew I've
seen is about 90 degrees, when I worked SM6CPY from W0ZV at a bearing
of 110 degrees (direct path being about 25 degrees from Colorado).  He
confirmed that he was receiving my signals from the direction of South
America.  IMHO this is not backscatter because the signals do not have the
characteristic echo sound of backscatter...although that does also occur
on rare occasions.  Geomagnetic skewing is very common...so much so
that I found 70 degrees to be my best Beverage to Europe from Colorado...
only when the geomagnetic field was very quiet (Kp <3) was my 40 degree 
Beverage best.

2.  The "long path" opening toward the south (usually SSE after sunset and 
SSW before sunrise) to stations on the opposite side of the globe is a
completely different mechanism and appears to be independent of geomagnetic
disturbances...it MAY be related to the terminator since it usually occurs
within 1 hour of sunrise or sunset...but nobody knows for sure.  No one has
explained it yet and some claim it cannot exist...but QSO's with 3W5, 4S7,
9M2, 9V1, S21, UA9 (Zone 18) and XZ0 are proof enough for me.  The fact 
that most (all?) East Coast XZ0A QSO's were made in the general SW direction 
before sunrise should be a clue that this propagation mode is VERY consistent 
with decent stations at both ends of the path.  I'm at a loss to explain
Milt's dipole comments which indicate high angle at his end because they are
inconsistent with the long path tests between A61AJ and N7UA (both using 
4-squares) last November.  Beverages are low-angle RX antennas like 4-
squares, and I would expect consistent results between the XZ0A and A61AJ
operations...so maybe XZ0A Beverages were not working correctly.  I can say 
that the XZ0A signal was VERY consistent here on Beverages (both at my 
sunrise and sunset...although XZ0A was very deaf at my sunset).  

        The long path mode will probably only represent 1-2% of your DXCC 
totals, but if you are serious about working rare ones, learn to watch for
it and have the right RX antennas in place when you need them.  

        If you are truly interested in working DX on Topband, here is what
should be done in approximate priority order:

1.  Erect RX antennas in as many directions as possible.  If I were in MN,
I would want at least the following (more is always better of course):

35  degrees - Europe for Kp < 3, Middle East Asia
70  degrees - Europe for Kp > 2, Africa
110 degrees - Caribbean and South Africa
150 degrees - South America and Sunset Long Path (SE/Central Asia)
210 degrees - Deep South Pacific and Morning Long Path (SE/Central Asia)
260 degrees - South Pacific, Australia, New Zealand, FE Asia (Kp > 2)
320 degrees - North Pacific and Far East Asia

2.  Listen, listen, listen...learn to switch your RX antennas often...your
ears and RX antennas are the best indicators of propagation.  You will hear
stations working DX you cannot hear but be patient...propagation may shift
to you eventually.

3.  Be patient and persevere...this is the sunspot cycle peak and 160 
conditions will not peak for 3-4 years.  Most of your EU openings will 
probably be in  the months of December and January...concentrate your 
activity then.  Think in terms of years and even decades...not months...
to achieve significant 160 DXCC totals.

4.  TX using a KW to a vertical of any kind with a good ground.  Transmitting
is the least important aspect of 160 DXing...the true keys are hearing, 
patience and perseverence.  Other antennas will sometimes work but a
vertical has proven itself to be best overall on 160.

        Good luck and remember, if 160 were easy, you probably wouldn't
be here to begin with.  

                                               73,  Bill  W4ZV