HF Propagation and DX - Cutting the guesswork using internet sources
By Brian Grist, G3GJX
SUNSPOTS ARE CRUCIAL............... The more we get the better HF conditions usually are. But coronal mass ejections are something else! They cause massive ‘solar winds’ consisting of high energy particles moving at close to the speed of light plus slower stuff which may take days to reach us. The ionosphere is usually adversely affected and HF conditions collapse. Sunspots come in eleven year cycles and we’re right in a trough at the present time, with many days lacking sunspots altogether! But, happily, the recovery happens quicker than the decline, so DX conditions will pick up in the next year or two. To see what’s happening to the sun on a day-to-day basis, click on: www.spaceweather.com. Meanwhile we have to make the best use of what DX openings there are. How do we do this?
A really comprehensive website is available which gives you all you could wish for in terms of solar forecasts, maximum useable frequencies (MUFs) plotted as contours on a world map, plus much more. Everything is automatically updated at 30 minute intervals or less. Click on: http://dx.qsl.net/propagation/index.html
To winkle out the DX it helps to find out in advance who’s going to be on from some of those hard-to-contact countries (or ‘entities’ as they are now more correctly known) and a well managed weekly newsletter is worth its weight in gold. Arguably the best available is DX 425 NEWS and the 425 DX Calendar, both available in several languages as well as English and sent weekly from Italy. You can read the current edition and a dozen or more back copies by clicking: http://www.mdxc.org/425dxn.asp Both of these items are available entirely without charge and come as cleverly constructed emails (no attachments). You can join the mailing list when you first visit the website.
To find out what DX is actually being worked on a particular band or bands, or using a specified mode at this moment in time, you need to look at one of the many Internet DX Clusters. There’s little doubt that DX Watch is a world leader. You can visit this website by clicking: http://www.dxwatch.com/. The first time you visit this site you get a short selection of mixed modes and bands,which is unlikely to be useful, so you should click on Filter Options and then choose the bands and the modes which interest you. This done you will find that the next time you visit the site the software remembers you and up will come your choices (which you can still amend anytime).
Not good at identifying some of the newer callsign prefixes? Choose from the list, point at the call and up comes the country and, if the station is part of a DXpedition, or other special event, a short description appears, usually copied from DX 425 News. You can also get more station details such as QSLing information and even an image of their QSL card if available!
It is also very easy to post the contact you have made with a choice piece of DX. The lists are updated at 1 minute intervals and, unlike some DX clusters, this one doesn’t seem to easily get swamped during big contests!
Until you become familiar with DX Watch you need to remember that it is a truly worldwide Cluster and for example, you may see a Pacific Island callsign is currently being worked by several W6’s. But with propagation like it is these days, you’re probably not going to be able to hear the DX if you are in Europe!
Despite what’s been said so far, it’s often handy to have a printed copy of callsign allocations like the ARRL DXCC list of current ‘entities’. Click on:http://www.remote.arrl.org/awards/dxcc/dxcclist.txt
Many of the special callsigns being issued at present aren’t included in the ARRL DXCC list so it’s worth printing off a list of the basic international amateur radio callsign allocations. Do this by clicking: http://www.dxing.com/callsign.htm
Having found your DX and the QTH how much do you know about the country, the island or the political status of the place from which they are transmitting? Thanks to a remarkable website called HamAtlas you can now find all these details, often including the country’s flag, the currency, and any political ties with other nations. Most useful, however, is the detailed series of maps that are probably most valuable when seeking information about some of the tiny islands and atolls to which big DXpeditions may go these days. Click on: http://www.hamatlas.eu/
Brian Grist G3GJX