So just how sporadic is sporadic E (Es)?
Time and again I have been struck by just how unsporadic Es is. OK, good days are random but there seems to be a pattern that more northerly and Scandinavian stations on 10m and 6m are better later in the day and later in the season. I actually wonder if these more northerly reports really are Es at all. There is every chance I am totally wrong, but I have noticed this over several summers and I question that Es is truly “sporadic”. I’d be interested to hear the views of others on this.
One thing is certain: we still have a great deal to learn about E-layer DX propagation. Es is certainly a fact on many summertime EU QSOs on the higher HF bands and 6m, but I am sure the multi-hop explanation for some very long distance QSOs is not right.
I absolutely agree that multihop is not happening here. We know that significant signal is lost on each hop. I believe some form of ducting may be taking place here, in my humble opinion.
I was interested in DX-TV for 35 years when Test Cards carrying TX idents were used. On Band-1 TV which equates to the 50Mhz band I can say for certain that I have only ever seen two-hop taking place. One has to remember that these Tx’s were in the region of 250Kw+. I am quite certain that the idea of Multi-Hop is so wrong because if it was to take place I would have seen more than two-hops. When these Tx’s were active you could also note that there was an underlying weaker mode of propagation that was there for hours with the stronger propagation which is commonly called Sporadic-E overlain.
To call it Sporadic-E is also wrong as it’s not Sporadic, we know when to expect it. I refer to it as E-Layer propagation.
I like Roger think that some form of ducting is taking place.
On asking a TV-DXer in SE Asia about whether he has seen more than two-hops the reply was no! and he’s been TV Dxing for 45 years.