The drama of 144MHz Sporadic E, and how I nearly gave it all up.

Here's the thing about 2m Sporadic E ("Es"), it is very dramatic.

I was sitting here on Sunday 11 July 2021 at 15:59, musing over my previous successes and failures during previous attempts to work 2m Es. I was ready for an opening, but so far it had not happened.

For some time I have been learning how to apply my hardware set-up to try to be prepared for 2m Es openings. For instance, on 8 July I had been ready and I worked  IK8BIZ, IK6DTB, EA2Z, EA5TT, IU4CHE, IZ7UMS, IZ7UMS, IZ8OFO and IK0IXO in an hour long whirlwind of 144MHz Es. Key to this was that I was forewarned by activity on 70MHz.

That was common enough for me not to mention it on this blog at the time.

Just to put some context round this, my time trying for 2m Es from here had a very poor start. On 10 June 2011 I worked EU7AA on 2m, a distance of 2070km, and my only 2m contact of the day. It came as a complete surprise at the time. Of course I knew it was 2m Es because I had knowledge of 2m Es from before we moved here, but I was still in the dark about how to manage that aspect of VHF propagation. Looking back at the log, I had worked two stations in Estonia minutes before on 70MHz. If that was today I would have been watching 2m and be ready to pounce.

At the time I looked at "Make More Miles on VHF" and that site, which was focused on 2m Es, suggested that I might find three or four 2m events in a year, and those were almost entirely located in the Mediterranean or over the Alps. None of them came anywhere near Scotland. This seemed to me like an unpredictable means of propagation now that I had relocated north to GM-land. I decided not to go looking for 2m Es, and indeed I thought very hard about giving up on 144MHz entirely.

After that I did not work any 2m Es for four years, until three Italian stations popped up in June 2015. Those were the only Es contacts that year too. Make More Miles appeared to be correct - 2m Es was something that was welcome but not predictable enough to spend time looking for.

So what I was sitting here mulling over was - what has changed now that I think I can rely on finding multiple openings each year? I pulled out some facts. Up to that point in July 2021, the years so far has produced 55 2m Es contacts into 11 countries and 35 squares, with a best DX being IT9GSF at 2333km. 

2011, one QSO, 

2012 zero, 

2013, zero, 

2014 zero, 

2015 three, 

.... (must work these ones out)

2020 22, 

2021 so far, 55 (make that 77 by the end of the day, see later)

Then, to interrupt my pondering, up popped S58P to start a 90 minute 2m QSO-fest.

144MHz contacts (all over 1050km) at GM4FVM on 11 July 2021

22 QSOs in 8 countries. Dramatic or what?

If I include two tropo QSOs with GM and G, that brings me to 10 countries worked in just over an hour. Unlike 2011 I was prepared for this to happen and I reacted quickly.

DX Maps looked like a bad nosebleed (I have been having a few of those lately), so many stations were in the mix ...

144MHz on a 15 minute slice on DX Maps on 11 July 2021

And just to backtrack, I was interrupted by this opening. I had been musing on how much more common this has become. Basically I was analysing while I was waiting for it to open, when it opened.

Returning to my earlier thinking that day, I had done this map before the opening started.

144MHz Es contacts at GM4FVM 1 January to 10 July 2021

Not a bad map and it excludes the contacts in the first map above.

So has 2m Es got easier since 2011?

I know that I have mused about this before.

The subject came up in an email conversation with Andrew, G0JCC, and I suggested that FT8 is a big factor. He raised several things which affect 2m performance as well. These included better radios and better antennas. Also more information like DXMaps and alert emails. Certainly we did not have those before. He is correct.

Another key factor Andrew reckons are better receivers. He and I both have mast head preamps. Although their influence may be smaller on 2m than on 70cms or 23cms, they still help a lot. Correct again.

Everybody's setup will be different and will be affected by these many of these factors to a greater or lesser degree. In my case things that go with the grain here are using FT8 and more use of the lower VHF bands.

I doubt if FT8 really makes much difference in terms of distance reached, but getting us all listening on and calling on the same frequency has made a huge difference for me. And so has much more activity on 6m and 4m which makes predicting 2m Es so much simpler.

Since speaking to Andrew I have signed up for a 2m Es alert. I did it at www.gooddx.net who also do my 4m alerts. I was stuck in the past thinking that 2m Es was not for me.

Back in 2014, with no 2m Es worked since 2011, I almost gave up on 2m entirely.

Now in 2021, my analysis of previous successes on 2m Es this year was interrupted by another big 2m Es opening.

And during the opening on 11 July, I was called by Thomas SV8PEX. That would be a new country, and Thomas is 2406km from me, so a contact would also be a personal best on 2m Es. Of course I called him many times. We did not complete a QSO.

210711_161600   144.174 Rx FT8    -20  0.8 1752 GM4FVM SV8PEX JM99
210711_161618   144.174 Tx FT8      0  0.0 1750 SV8PEX GM4FVM -20

Later Thomas emailed me. He is as keen to work me as I am to work him. He confirmed what I had thought, that there was a large tropo duct in the Adriatic Sea, and that must have connected to the Es event. He said that he was hearing me for a long time, but he could not get through the pileup (!!!).

Maybe another duct, at either end, may make this possible eventually. My best 2m Es DX is still 2333km so it is not totally inconceivable. However, earlier in July I had emailed G0JCC with my view that working SV from here was "not practical". Clearly, once again, I don't know what I am talking about. Or maybe all those factors have changed my mind.

Still, SV8PEX heard me, and I heard him. That is good, but not a QSO. Next time, maybe.

I think that 2m Es is easier than it was, thanks to all these factors. However, it is still the ionosphere which calls the shots. However good your equipment, you still need nature to co-operate.

And, of course, I have my superior intellect to help me outwit the Laws of Physics.

Plus my often mentioned modesty and humility.

73

Jim

GM4FVM

Summer is here (I think), and why are my reports always worse than theirs.

Ah, Summer.  Midges, flies, wasps, ants, too hot to sleep, sweaty days, noisy neighbours at stinking barbecues, traffic jams, cafes full of day trippers, grass cutting ... don't you just love it?

No, I do love it. There is the Tour de France, Cricket, long warm evenings, and relaxing beside the radio.

I know when it is Summer because the local flocks of alpacas sit down in the field rather than eat the huge banks of grass which the warm weather produces.

The Ayton Law alpacas, a recurring topic in this blog

They have been shorn again. This seems to happen a lot but early July seems a bit late to me. I thought they only gave up their fine wool once a year, but what do I know?

I find that my knowledge of small domesticated camelid shearing is much like what I know about radio propagation. I do not really know very much. Clearly they are both complicated subjects. However, I can observe what is happening, and maybe I can learn from that experience. These things can surprise me but they are very common so I should take note.

I mean, what is unusual about alpacas? It all just happens whether I take note or not. Like radio. So take note and learn from what you cannot change.

On the other hand do I actually need to understand the processes involved? Is there not a chance of just looking and marvelling without really comprehending in detail what I observe?

Perhaps there are some things I might never understand.

Hmmm.

Anyway, June has ended with a long-ish Es event on 2m and I managed to get into part of it. Then there was also a fairly long tropo event which I managed to participate in for most of the time.

It all brought a reasonable map for June on 2m

2m contacts at GM4FVM during June 2021.

As usual, click the image to enlarge if necessary.

The Es openings accounted for my contacts into Spain and Portugal, while the tropo explains those across the North Sea. What I missed was an opening into Central Europe. Ah well, there is always next year (maybe ....).

Basically, it is astounding. 13 countries in 44 squares in a month with no EME or meteor scatter. All Es or tropo. Remarkable. When I was G8JWG I would have doubted such a thing was possible, never mind that I would do it without trying very hard. Plus I was away for a number of days during June.

On 4m I might rue that fact that I "ONLY" worked 19 countries, down from 25 in May. (But 25 is a huge number, Jim, so it was bound to be less the following month)

These are the sorts of figures which amaze me. I know I keep banging on about my station, but it is not in the superstation category. I do not want a superstation. 7 elements on 2m where I have just over 200 watts, and about 100w on all the other bands. Antennas just sufficiently high to clear the roof tiles.

Enough already.

I had some email correspondence with GM3PPE. Mike is always interesting. He was raising the subject of antenna height gain and the possible relationship between antenna height and differential signal reports.

Spurred on by his line of thought, I did some analysis on a random (?) slice of my log book. This confirmed my feelings, which mirror Mike's, that I give better reports than I get. The section of log is posted below but you will definitely have to click that one if you want to study it (personally I wouldn't bother to study it if I was you).

Random slice from the GM4FVM's VQLog log book

It has changed slightly from when I did the calculations - one doubtful contact has since been confirmed. I disregarded the doubtful ones. "Doubtful" and "failed" contacts appear in orange, but sometimes doubtful ones get confirmed later.

And, yes, EA4T was a treble, and he called me to complete it so it is not just me who chases these things.

Anyway, when I worked it out there were 43 valid entries then and the total was 28 times I gave them higher report and 12 times they gave me higher with 3 exactly the same. So, yes, I do give better reports than I get.

That does not give the full story. I gave two of those 34dB better than they gave me. Two of them! The highest the other way was someone who gave me 15dB more than I gave him. 

I remember the few instances of big numbers in the different reports. I forget the many smaller differences. When I average the whole thing out, even with two 34dBs in there, the difference taking all 43 entries into account is 3.5dB. While the massive differences might have caught my eye, the reality is not so bad. 

My final conclusion after all this waffle is that there is evidence that I give better reports than I receive. I doubt if my antennas, or my lower power or my titchy masts, are to blame. Many stations have higher noise levels than me, some use lossy analogue audio connections, and some use a lot more power than I might expect.

Then there is rapidly changing propagation. But would it always change to benefit the other station's reports? That is a mystery just like alpacas.

Perhaps nobody knows.

Or perhaps it is just not worth finding out. 

Or maybe I am happy with the results I am getting (see map/log).

Apparently the BBC do something to inform the public about alpacas. I have been told to watch "Nuzzle and Scratch". Seemingly it is about my level, or so Mrs FVM says.

Not sure what that is but I must get on to finding out.

Or not. 

I did mention I am paranoid, didn't I?

73

Jim

GM4FVM