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Software
review
DX
ToolBox propagation analysis and prediction program (II)
Solar
and Geomagnetic Data
The
“Solar and Geomagnetic Data” window displays 5 bar-graphs with
the next readings:
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Daily Solar Flux (named Fs or I or other products)
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A-Index
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Smoothed Sunspot Number (SSN)
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Background X-Ray Flux
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K-Index forecasted for the next 3 hours.
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The "Solar
data" window and the cursor showing a K-index of 9 on
July 27, 2004. |
The
value of each plot can be highlighted by passing the mouse
over the bar.
These
data are a graphical representation of the GOES 10 and 12
satellite
readings. They are as important as the X-ray flux. Higher
is the solar flux and the number of sunspots, higher will be
the MUF (maximum usable frequency).
A
low A and K-indices associated to a low X-Ray flux will improve the
propagation. However, a high individual value can break an
ionospheric layer too (K=9 for example is the sign of auroral
activity).
These
data have thus to be interpreted with care with a good knowledge of
the dynamic of the solar and geomagnetic activities, which obey to
very complex mechanisms where interact strength fields with plasmas.
In
all five charts, bars
change gradually from green to red color according to the index
value. But at mid-scale the color is green-reddish, a bad color that
seems "fuzzy" or screen, not pleasant. I
suggested to the publisher to allow the user to change the color and
maybe the type of chart because the green-apple color looks a bit too
fluo on screen.
At
last as we told previously, if you work offline, if you try to open
this window the program
displays an exception fatal error and shuts down. The same problem
occurs randomly
working online in trying to open this window before any other one
excepting the Current conditions. This fatal error should be handled
by the system or corrected in a next
released of DXTB.
Images
The
“Images” window allows you to display near-real-time images
or graphs downloaded from various servers such as SEC/NOAA
without user intervention but one mouse-click.
Among
the images downloaded, name the auroral oval, several
maximum F layer frequency charts (related to
MUF) calculated over various parts of the world, the last images of
the Sun recorded by SOHO, etc.
If
you are searching for other reports, bulletins or pictures to add to
this list, I suggest you to check the SEC
Data Library.
Now,
to
update the list you must close and re-open the
“Images” window for the changes to take effect. The new images will appear
at the end of the list.
Do not enter an URL to an image which name changes every day or you
will get an error… Select only those using a generic name.
NB.
On July 28, 2004, the publisher fixed a problem that happened when
loading images on XP/ME. Only the first or first two loaded. The fix is installed in DX ToolBox version 2.2.0 exe file which is also slightly
smaller that the previous one.
Reports
The
“Reports” window is very interesting to take knowledge of the
latest bulletins, warning messages and other text reports released by
observatories monitoring propagation conditions or the space
weather.
In
the current
“Reports” window you can only read one report at a time. I
suggested to the publisher that it would
be interesting to create a multi-instance object of this window in
order to access simultaneously or so to several reports displayed in several
windows in
order to compare easier several documents side by side.
These
reports come from
the
SEC FTP website.
Not
all are “clear” and understandable for the novice or even
an advanced amateur. Most require to be
familiar with the solar and geomagnetic activity and some require
even to know some codes to translate figures in text…
Excepting this, several reports are however accessible to
everybody.
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The
following reports are available :
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WWV
Geophysical Alert
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27
Day Space Outlook
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45
Day AP Forecast
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Geomagnetic
Data
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Daily
Geomagnetic Data
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Daily
Particle Data
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Daily
Solar Data
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GEOALERT
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Daily
Magnetometer Analysis Reports
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Hourly
Magnetometer Analysis Reports
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Predicted
Sunspot Numbers and Radio Flux
-
Report
of Solar-Geophysical Activity
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Solar
and Geophysical Activity Summary
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Solar
Region Summary
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Weekly
Highlights and Forecasts
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Current
Space Weather Indices
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Space
Weather Event Reports
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Daily
Space Weather Indices
-
Summary
of Space Weather Observations
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3-day
Space Weather Predictions
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The
Grayline Map
As its title suggests, this window displays a
gray line map of the world in cartesian projection. The gray line
is not correlated with the sun activity but we know that this line separating
the day from the night (also called the terminator) is the
location where low and medium altitude ionized layers vanish
on the night side permitting sky waves to reach the F-layer, and thus to reflect
further with less hops, and the opposite on the daylight side.
Using the gray line is an excellent method to reach far DX.
First
error, the program doesn't check the date format. The default format
is MM/DD/YYYY. If you enter DD/MM/YYYY the program accepts the entry
and calculates something even if the month is greater than 12 but it
doesn't update the map.
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Thanks to the Propagation
Path calculator,
clicking anywhere on to the Grayline map you can get the propagation conditions
at the target location, its longitude and latitude (roughly,
without decimal), distance in kilometers, as well as the
antenna bearing.
On request you can display the short path to the target
location but there is no possibility to display the long path and get a
propagation chart for this antipodal direction, although it
is often very useful to take advantage of the darkness to
reach far DX.
At
the limits of the map or close to the pole the program shows
also some erratic paths because high angular values are not
correctly taken into account (see p3).
DXTB provides also a beacon monitoring incrusted on the Grayline map.
You can get the location and call sign of the currently
transmitting NCDXF/IARU beacons
in selecting the right frequency (14100 kHz, 18110 kHz, etc)
in the scrolling dialog box displayed in the below right corner of
that window.
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The “Grayline Map” window with IARU beacons monitoring
activated on 14100 kHz. At foreground the "Propagation
map" predicts a 7 dB signal (S5) to 5Z; in the field in
was S1 only. |
For
the publisher, in inserting this feature the idea is to
allow you to (try to) listen simultaneously to the various beacons in
tuning your radio on their frequency. The next page devoted to SWL
activities recalls how work these beacons.
Most of them use vertical antennas (isotropic radiation) at medium or low power (100
W to 0.1 W) and help many amateurs to “feel”
the radio propagation conditions and openings toward such or
such country (or to be accurate from the DX to your location).
Added to the other tools provided with
DXTB (Propagation path and MUF/LUF estimations), you will better understand why such or such beacon
arrives loud and clear to you or is unreadable.
Sometimes
however, the signal strength estimation displayed in the
"Propagation map" does not match the
real conditions experimented in listening beacons or working
DX stations, that they are close or far away from your home.
We are here outside the capabilities of the program because
it is a prediction tool working with median and monthly
values, suited to estimate
future conditions not to "forecast" the current
status of the ionosphere in spite of its real-time updates.
At so short-term propagation conditions fluctuate at a scale
by far smaller than what permits the current ionospheric
sounding network. That
said, to get a better estimation
of the signal strength and chances to work such or such DX,
the program should also take into account a complete communication
circuit and not only the locations, date, time, SSN and the output
power. We will come back in
detail on this
subject in the last page.
Last
chapter
Propagation
Map
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