I think of the Solar Cycle as being like the annual climate chart, changing over a longer period of 11 years, but vaguely predictable in the long term. VHF propagation is more like the weather, seemingly changing at random week by week and day by day. Here in IO85, also like weather, VHF propagation can change minute by minute. (I will avoid the Doobie Brothers reference which would have been Minute by Minute - I keep holding on).
The 11 years Solar Cycle may bring F-layer propagation, increase TEP, or decrease aurora as it passes along, but its influence over Sporadic E is debatable. In fact, what causes Es to vary like the weather is a mystery. Take the last two weeks. Two weeks ago on 70MHz I managed eight QSOs, not much to report for a seven day period in late July. Of course I blamed everything from my station to some of the more kooky theories about Es. Eight QSOs to seven squares in five DXCC in a week. Best DX was not bad at 1859km to EA6SX but for this time of year those were slim pickings.
I was comforted by the old saying "what goes around comes around". According to this, things balance out in the end. A more scientific approach might be the statistical concept of "reversion to the mean" which states that if things are unusual then they usually go back to normal soon. So maybe next week would produce a bumper catch of stations to compensate for a thin netting the week before. What are the chances of that happening?
"Patience dear boy" as someone might have said. Me? Patience?
Last week the next seven days duly delivered. It reverted to the mean. I had 59 QSOs to 15 DXCC in 43 squares. Even the DX was better - EA4L at 2122km.
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| WEEK ONE - 70MHz contacts at GM4FVM - 22 to 28 July 2025 |
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| WEEK TWO - 70MHz contacts at GM4FVM - 29 July to 4 August 2025 |
As usual, click on the images to enlarge them if necessary
So one week's Es is different from another. What does this prove? Well, whatever the figures say for me it is mostly about things which are all in the mind. as well as the propagation. There are lots of random factors at play with things like this. For example, was I at home, in the shack, waiting for a contact when an opening occurred. Was there anybody else at the other end in a similar state of readiness. Were we both likely to use the same mode? What about the time difference (like me doing my post-22:00 round up when it is after midnight in Finland)? Was there an opening to the West where only the cold grey Atlantic lies to swallow up my radio signal?
The thing is, after the first poor week I might be tempted to give up. I might think that 14MHz or digital voice could certainly be easier (perish those thoughts). Perhaps it is all in the mind, but that first week could have put me right off trying again.
Things got better later. With such a random set of factors set against a pretty chaotic propagation background, OF COURSE there will be weeks when less happens. There will also be weeks when lots of things happen. I have to take the rough with the smooth.
The sunspot numbers change, the weather changes and tropo propagation comes and goes just as Es does. It helps to have several bands to use. I worked V51WW on what was probably Es-linked 6m TEP. Also, two PY stations probably on multi-hop Es.
Things often get better if you keep trying. They would get better anyway whether you try or not, but if you are still trying at least you will be there to witness it.
73 Jim
GM4FVM
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