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Vecchio 21-12-17, 14:51   #1
IU0BMP
Senior Member
 
Registrato dal: Jan 2014
ubicazione: Roma
Messaggi: 92
Re: Vale la pena organizzare grandi dxpeditions durante il minimo solare ?

ENGLISH TRANSLATION

Is it worth organising big dxpeditions during a solar minimum?
This question, that, personally speaking, has surprised me, has caught on among Dxers and, I’m afraid, also on those people who do organise and conduct such Dxpeditions.
Well, let’s first clarify that a solar minimum is a period in which the Sun has few, if any, sunspots, thus limiting the use of the higher HF bands. It’s a natural and regular phenomenon that has taken place for billions of years, we assume… or for sure, since when we have been observing the solar activity, that is, almost 500 years now.
At the end of a solar cycle, there is a period of low, or very low, solar activity, lasting about 4-6 years, depending on a cycle’s strength, before climbing back towards the next maximum.

So, there is nothing new; many of us have got out “unscathed” from many solar minima and the current period is nothing exceptional, compared to the past.

Click the image to open in full size.

Let’s see now, by drawing on our resources, whether during the latest solar minimum, (roughly from 2006 to the first half of 2010, as you can see in the above diagram) there have been big Dxpeditions or not, taking into consideration certain criteria such as distance and rareness of the Dxcc entity having been activated.
The worst period was between 2008 and early 2010, often spotless, SN=0.

In that timeframe, I soon find VP6DX, Ducie island, 2008 (almost constantly spotless…) 183.000 QSO; I remember having worked it myself from 15 to 80 meters. It has been one of the three most successful Dxpeditions ever, in terms of number of QSO!

N8S, Swains island, 2007. A polar path for us in Europe, hence not as easy as Ducie, 117.000 QSO; I remember hearing and working them on 20 and 17 meters.

3B7C in 2007, 137.000 QSO, 10-80 meters for me.

K5D in 2009, 115.000 QSO, 15-80 meters for me.

ZL8X Kermadec in 2010, 148.000 QSO, in my log 12(!)-40 meters.

VK9DWX, Willis in 2008, 95.000 QSO, in my log 10(!)-80 meters.

I could go on; I took the list from the German site GDXF.

Therefore it seems evident, without much doubt, that even during a solar minimum, it is possible to conduct DXpeditions to “most wanted” entities, generating very high QSO numbers, making happy a lot of people anywhere in the world, not just the closest and easiest areas in regard to the Dxpedition’s QTH.

Sure, 10 and 12 meters are often closed (even though there are exceptions, as you could see in the examples above…), but that’s no big deal; we have 6-7 more bands where QSO are possible, considering that the Dxers’ average equipment has improved over the years and so has the equipment used by the big Dxpedition teams. Don’t forget that, about 30 years ago, most Dxpeditions often had only a single tribander and a vertical…
Add to this the new tools, such as online logs, often in real time or with frequent updates, real time propagation forecasts, the reverse beacon network and more, all allowing to take full advantage of any small and marginal propagation opening, saving the Dxpedition operators many unanswered calls as well as helping Dxers work the Dxpedition without spending hours in front of their rig.

Now I’ll go further…

Considering propagation, we know that polar paths, i.e. paths passing over the North or South magnetic poles, are the worst, being the most affected by space weather phenomena (flares, solar wind originating from coronal holes, etc.). Polar paths are also the most prone to decreasing MUF in low solar flux and low sunspots conditions.
Are there rare countries, most wanted entities where to conduct Dxpeditions during the solar minimum, NOT passing through a polar path from everywhere in the world?

The answer is obviously no; any given area in the world has some other area for which the most direct path goes over a pole, but we have to reconsider the definition of “world”. To start off with, landmasses are not evenly distributed on the Earth’s surface, let alone hams in those landmasses! ��


If we take into account the areas with the highest ham population density, we can identify 4-5 areas
, that generate the highest QSO numbers in Dxpeditions’ logs: North America, East and West coast; Europe and European Russia; Japan and Far East.
This is what the raw numbers say, without however neglecting other areas where several Dxers are present.

Click the image to open in full size.

Restricting our analysis to these areas, of course considering that landmass distribution, as well as islands and “most wanted” entities position, is not even at all, we see that, yes, there are places where polar paths from the main areas can be avoided (or minimized...)

Which could they be?
Well, at a glance, looking at an azimuthal map centered on southwestern Pacific, near the Australian coast, all those VK9’s, FK/C, C2, T33, just to name the rarest entities in that area, are quite an easy shot for us Europeans as their paths don’t get too close to the pole (you have to consider the North magnetic pole, near Northern Canada, not the Geographic North pole…). The paths to Japan and North America from the aforementioned entities are also quite easy.

Click the image to open in full size.

Again, CE0Z-X, 3Y0P, VP6 in regard to the areas with the highest ham density are not interested by polar paths, except maybe marginally in a few cases.

Click the image to open in full size.

PY0T-S
are not a polar path for any main area and quite easy for NA e EU.

Click the image to open in full size.

ZD9 ZS8 3Y0B FT5W/X, all that belt in South Atlantic and South Indian oceans are not a polar path for anyone. The South Indian ocean can be tricky for the US West coast, but not impossible, so it can be considered for sure.
Of course, most of Africa, (even though there are no real most wanted) can be interesting for NA and Japan, with entities such as E3, 3C0, 9Q, TN.

Click the image to open in full size.

The Caribbean too, with KP1-KP5, HK0 are quite simple for EU e NA of course, much less for Japan, but they could be an acceptable compromise.

To be avoided, if possible, the central Pacific entities such as KH1-3-4-7, that are full polar paths in Europe, being almost impossibile to work in certain times of the year, (the upcoming Baker Dxpedition in midsummer comes to mind!) or some Asian entities like A5, XY, VU7-9M0 that are difficult for North America, even if they are not most wanted anymore.

Click the image to open in full size.

Click the image to open in full size.

So, as you can see, if you want to avoid polar paths toward the main ham areas, it is still possible to find many most wanted entities to activate during a solar minimum with very good results and many QSO with Dxers in the World.

Apart from this futile research of mine, all those past Dxpeditions speak for themselves, very successful operations conducted anywhere during the latest solar minimum, proving this.
Therefore, there are no excuses. Do not blame the propagation. Propagation is always there. Let’s encourage the big Dxpedition teams to devote their efforts, giving us some fun, suffering the cold or heat on a rocky guano island, while we sit on our armchairs, criticizing them on the social media as long as all this lasts… :/
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Fabrizio (Ex SWL-Fabr), Roma.
IU0BMP non   collegato   Rispondi quotando
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