Monday, 25 June 2018

The solstice, 6m propagation and Clublog

Ah, the Summer Solstice.

The longest day in the Northern Hemisphere has passed and as I write it is still officially daylight here between 03:24 and 20:58, and given daylight saving time and a clear night, you can still work outside without lights at midnight. (Why would you want to do that, Jim?)

Sporadic E propagation is largely (but not entirely) a Summer phenomenon, so you would expect it to peak at the Solstice. The Earth is tilted as it rotates, and the axis of rotation turns relative to the Sun in about 365 days. Well, it seems like that to us, but the reality is that the angle of the poles is more or less fixed and the Earth rotates round the Sun in 365 days or so. This creates the effect we see as the four seasons.

The Sun sends much the same levels of energy towards Earth all year, but because of the tilt in the Earth's axis of rotation, the angle of the Sun's radiation changes. This makes little difference at the Equator, but up here is lofty 56 degrees North we find that the angle of the Sun varies a lot during the year. Katy, the Shack Cat, knows that the Sun only warms up a sheltered part of her garden for two months on either side the Solstice.
Katy enjoying her first sunny day of the year in the "Bermuda Triangle", 20 April 2018
The triangular flower bed in the garden gets no direct Sun for the other eight months of the year. It gets the full blast for the longest period at the Solstice, but by then Katy has abandoned it as too hot. Then she is to be found under a bush. She will be back there towards the end of August for her final sun bathe of the 2018 season.

Sporadic E is a bit like our triangular flower bed. As the angle of the Sun rises during the period on either side of the Solstice, so "clouds" of Sporadic E form further and further away from the Equator until they cause the VHF bands to open to operators as far north as GM4FVM. Like the angle of the Sun at the flower bed, the angle rises to a point where ionisation occurs in the northerly E-layer. This is good for GM4FVM and also for Scottish cats who can stay warm in their gardens.

You might think then that at the Solstice itself there would be an awful lot of Sporadic E. Not so, at least not in my experience. If you want to enjoy the Es bonanza of working round Europe with ease (or single skip Es wherever you live), then 21 June is not the day to do it. For some reason which I do not understand, the Solstice week has never been good for single hop Es for me. Mid June and the first two weeks in July seem better. At that time the Sun is high in the sky but not at its maximum.

What I do find is that the time around Solstice is really good for multi-hop Es. This is the time of year when stations in Europe become transfixed by the rare opportunity to work Japanese stations on 50MHz. This is multi-hop Es at its best for us. It isn't just Japan either, with stations in China, India and the Philippines joining in..,

EDIT I used the wrong photo here before !!!

I heard DU7/PA0HIP who, at 11138km, is the most distant VHF station ever heard at GM4FVM. This sort of thing might have been possible at the peak of the solar cycle a few cycles ago, but for it to occur at sun-spot minimum due to Sporadic E is amazing.

When this window of multi-hop Es was first described, the Japan - Europe path was thought to be some unique phenomenon. That idea has been largely discounted as similar paths have emerged elsewhere.

Japan to here is about 9000km, and I am hearing Japanese stations on 6m almost every day.
Path of 6m signal from DU7/PA0HIP, with JA6BZI for comparison.
The paths shown from GM4FVM are partly over the Barents Sea or the Gulf of Bothnia but principally over land. Most European stations have paths to South East Asia which are entirely over land. Most days around the Solstice I start hearing JA stations at about 07:30 and they can continue until about 10:00. Sometimes I can hear six or seven in a day. The openings are short: perhaps I receive two or three overs from any specific station. On the other hand, some stations like JA7QVI, appear repeatedly on successive days.

The path to the Philippines is a good 1000km further than the path to Japan. Could there be other options which have not been tried?

So what has changed to allow me to see this path? I first heard JAs in June about three years ago on JT65. Since then I have improved my antenna and coax. For such short openings JT65 was not ideal with its 1 minute tx period, whereas FT8 with its 15 second periods may be better. Having said that, FT8 is about 4dB less sensitive than JT65, so it is swings and roundabouts. More likely we are all just looking for all this more carefully. Previously it was used mostly by CW operators, but the arrival of lots of FT8 operators, all on the same frequency, raises the chances of detection.

Can I work these Asian stations? Probably not. I only use 200W, and most of them are using 1kW. Perhaps if I had a bigger antenna it would be easier too, but then I am not interested in either of those options. The openings are so fleeting that it hardly seems worth doing it anyway. Other stations located further south in Europe are better placed and good luck to them. I am happy just watching it.

Mind you, with one or two of them at signal strengths up to -2dB I might be able to work one someday .. and I do try sometimes.
PSK Reporter map showing GM4FVM receiving DU7/PA0HIP on 20 June, and the "Russian Gap"

Obviously with Es being influenced by energy from the Sun, the path is entirely in daylight. Only a small part of the bottom right hand corner is in darkness as night spreads across the Pacific Ocean and towards Japan.

In an Easterly direction from me there is a huge gap in 6m stations between Europe and South East Asia. The large hole in 6m coverage to the East is largely accounted for by Russia, and in Russia the 50MHz band is used for television. This "Russian Gap" limits what we know about Es propagation and it would be very helpful if Russian amateurs had access to the 50MHz band (or the 70MHz band for that matter, which is occupied by sound broadcasting).

To the West as far as the South East we have amateur stations!
6m contacts at GM4FVM in the month up to 25 June 2018
It is apparent from this that I have finally worked another continent on 6m, South America. It took ages but finally I worked PV8DX on 12 June. This particular contact proved rather difficult as the competition from big stations in Europe was preventing me from getting through. Being this far north has one advantage - it gets dark later in Summer. Thus when most of Europe was in darkness (and had lost the path) it was still bright at FVM Towers and still light all the way to Brazil. At 21:15 I worked into South America on 6m for the first time. You can see from the map this this path was actually shorter than the one I recently used to work Mexico, so my best DX on 6m has not changed.

The key factor in this latest map has been Clublog. For ages I have been thinking that I am getting lazy, especially on 50MHz. Up to now, once I have worked a station or a square and added it to my all-time list, I don't work the same place very often. In fact, I was in the habit of just sitting and watching for new ones. I know that many twitchers (bird watchers) have annual lists and all-time lists, which keeps them busy in the January to March period. If I had an annual list I would start the year working places like France, which, to be honest, isn't a great stretch DX-wise from here. However, even French people deserve to work IO85.

But how to do it? Could I analyse my log to break down contacts into years? And how can I compare 2017, when I was not chasing annual targets, with 2018, when I was?

The solution came with Clublog. Clublog looks to me like a tool written for HF types. But it has an annual DXCC table which extends as far into the dark territory of VHF as the 6 metre band. No good for 4m or 2m, but how was I doing at 6m?

Terribly badly.

In 2017 I had worked 50 DXCC, and in 2018 only 42. It quickly became clear to me that I have not worked many European DXCCs in 2018. Laziness indeed.

With renewed vigour I pursued the missed targets, like Ireland (!), Luxembourg, Czechia, Slovakia, Romania, Bulgaria, Iceland, and many other obvious targets within easy reach. Within a week I had got my total up to 52, and there are still a number to be reached, like, surprisingly, the Netherlands. Yes, this annual list has definitely got me moving at last.

The point here is that my laziness had gone without notice. Once I got Ireland into the all-time list I had not even noticed that it was missing this year. Does that matter? Well it does if you are in Ireland and you want to work IO85, or even just work plain old Scotland as a DXCC. Amateur radio is not there for me to exploit in isolation. I have to offer my DXCC and square for others to work. I need to be there working other stations, for if everybody was lazy nobody would ever get anywhere.

Tch, tch, Jim

Getting onto Clublog is easy once you have joined. If you have an electronic log like mine (EA6VQ's VQLog) there is a box marked "Upload Log" followed by "To Clublog". Once you have uploaded the log once, VQLog simply adds any new QSOs every time you click the box. You can keep your "confirmed" total right by occasionally updating the entire log with a file of your log which you have already updated with your QSL receipts.

Clublog offers lots of lists and comparisons. Not being very competitive, I compare myself with myself, but it is possible to compare with others too. We could start a "FVM Blog club" and compare ourselves if we wished. Maybe that is not a good idea.

Another useful service Clublog offers is to report faults in the uploaded log. It turns out that VQLog had been mis-placing SWL QSLs I have listed in my log under the wrong country (hardly surprising as SWL prefixes are often different). Also I had two countries worked which are not DXCCs, which we could quibble about, but anyway. VQLog seems to have put "2E0" calls from England into Scotland, and the fault reports alerted me to that. So now I have fixed lots of faults in my log (including a few entries dated 1899).

Finally, once I joined Clublog I discovered that I had been inconsistent with my treatment of cross-band QSOs. I have had cross band QSOs between 70MHz and 50MHz with countries which do not have 70MHz as an amateur allocation. For Switzerland and Austria I had got this right, for France and Sweden they were showing up as 4m QSOs. I doubt if I can count as a 4m QSO a contact with a DXCC which does not have that as an amateur frequency. So, rather reluctantly I corrected that error and guess what - my all-time 4m DCXX list has fallen from 40 to 38. Bah!

So Clublog has spurred me into working wonders for my 2018 DXCC list, and reduced my 4m All-time DXCC list. But hey, correcting an error is always the right thing to do.





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