Thursday, July 16, 2020

Unusual Sporadic-E opening on 144 MHz in N Europe hints at possibility of Trans-Atlantic contact

In this post, we'll look at a recent Sporadic-E opening on 144 MHz in northern Europe and what it might mean for a trans-Atlantic contact on 2 metres.

First, the opening...


There was an extensive opening on 144 MHz on the evening of Monday the 13th of July 2020 as can be seen from the graphic above from DXMAPS.COM

Sporadic-E openings on 144 MHz are reasonably common in Europe but they are usually much further south. Radio amateurs in say the UK or Ireland are likely to catch several openings to say Spain or Italy during the months of May, June and July every year.

It is very unusual to have a Sporadic-E in northern Europe and it is rare for the radio amateurs in the UK or Ireland to hear the likes of Finland or the Baltic states on 144 MHz via Sporadic-E.

While the graphic above gives an illustration of the extent of the opening, let's have a look at some specific examples. The maps below generated by FT8 reports on the PSKReporter website are useful for examining the extent of the opening.

EI2FG on the south coast of Ireland was one of the most westerly stations listening on the FT8 frequency on 144 MHz for the opening.


The longest path was to UA1ALD at 2416 kms and the signal was +9dB which was certainly strong enough for an SSB contact. Note the beam heading... 55 degrees. OH6KTL was up at 44 degrees.

Note also that the path was open only to the northern part of Estonia, there was nothing further south.

UA1ALD... This is the FT8 sent/receive map for UA1ALD.


Note how concentrated the footprint is in the UK. There is no-one from the south-east of England shown.

ES4RM... Note how the results for ES4RM in the north of Estonia are pretty much the same with nothing from the south-east of England.


OH2FQV... This is the map for OH2FQV in the south-east of Finland.


Note the difference in the footprint in the UK compared to UA1ALD. This time, there are a lot more stations in the south-east of England except for an area south of London.

This suggests that the Sporadic-E cloud responsible for the 144 MHz opening was probably somewhere over the north of Denmark. What each station worked or heard was dependent on where they were relative to this Sporadic-E hot spot.

It's also amazing to see just how many stations in England are using FT8 on 144 MHz!

GI6ATZ... This is the map from GI6ATZ in the north-east of Ireland.


The more northerly location of GI6ATZ results in stations in Lithuania and Latvia being heard.

G7RAU... The send/receive map for G7RAU in the south-west corner of England shows that there was a 2445 km path open to OH6CT in the north of Finland, just three degrees or so south of the Arctic Circle.


Again, note the beam heading from G7RAU to OH6CT which was 35 degrees. The signal was -2dB which would have been enough for a CW contact.

OH6CT... From OH6CT's viewpoint, he was hearing the south-east of England this time and the rest of the UK and Ireland was missing.


Trans-Atlantic on 144 MHz??? .....First of all, lets recap.

a) Both G7RAU and EI2FG heard or were heard by stations on FT8 in Finland at beam headings of 35 and 44 degrees respectively i.e. very far to the north.

b) Both G7RAU and EI2FG heard or were heard at -2dB and +9dB respectively at a distance of about 2400 kms. Note that this is about the maximum distance for one hop Sporadic-E.

Now lets look at the path from St.John's in Newfoundland to the south-west of Ireland and the north-west of Spain.


First off, the beam headings of 68 and 80 degrees are a lot further south than the beam headings experienced by EI2FG and G7RAU. If there is a Sporadic-E opening on 144 MHz in the north of Europe then why wouldn't it also happen out over the North Atlantic?

I know some might argue that Newfoundland is closer to the geomagnetic pole and that might impact on Sporadic-E formation but Newfoundland is also further south than Ireland.

While the one hop of 2400 kms ends up in the Atlantic, the remaining distance to span isn't huge. Just another 800 kms or so would reach the south-west of Ireland. Just another 1000 kms would reach Spain. Both of these distances could be easily bridged by a tropo duct forming over the ocean to the west of Ireland or Spain.

Surely there must be times when there are Sporadic-E openings on 144 MHz to the east of Newfoundland? And there must be times when these openings coincide with tropo over the eastern part of the Atlantic? I would argue that there must be times when the path across the North Atlantic on 144 MHz is open although I would acknowledge that these openings are pretty rare.

I'd suggest that one of the biggest problems is the lack of activity on the western end. I don't believe there is anyone in Newfoundland transmitting or listening on 2-metres for signals across the Atlantic. For all we know, some of the trans-Atlantic CW beacons in Ireland, England or France may well have made it across the ocean to Newfoundland but there was nobody there listening to report it.

Look at the distance from Newfoundland to the Azores (CU). That's within Sporadic-E or meteor scatter distance and yet as far as I am aware, there has never been a contact on 144 MHz from Newfoundland to the Azores.

Solution... The most obvious one to me is the establishment of a station on Newfoundland that can be operated remotely, just like D4VHF on the Cape Verde Islands. Something like two stacked 5-element Yagi antennas beaming at 70 degrees with 100 watts?

Digital modes like FT8 could be used to see if the path was viable by transmitting and receiving on the 2-metre frequency of 144.174 MHz.

It is of course easy to say how it might happen, it's another thing for a group to implement it.

6 comments:

Photon said...

Very interesting. The first question is: how does anyone know, for certain, with reasonable evidence, that this propagation is indeed Es? People react with anger when this question is asked, but nobody seems to have a reasoned response.

The northerly aspect of this opening is interesting from the point of view of middle atmosphere physics, conditions that probably do not occur much further south, at an educated guess. The same northerly aspect is required for northwern Europe-JA paths. Maybe this hints again at something other than Es.

I absolutely agree about the lack of effort on the western end of the Atlantic circuit. It's very surprising and disappointing. I think the crossing has more chance of being made to the Caribbean than mainland USA/Canada as things stand. In that respect, there's a superficially good set of conditions developing as I write!

HB9DUR Andrea said...

Excellent article John that opens our eyes. Tnx
Andrea HB9DUR

DK5YA said...

Take a look what happened 17 years ago, we were pretty close on June 26. 2003:
de DK5YA

June 26 2003 opening

John, EI7GL said...

Thanks DK5YA, I'll put this link here for reference... http://www.vhfdx.de/es_summary_03_june_26.htm

M0AFJ said...

It’s also worth looking at the QSO between D4VHF and SP5MXU at 5600 kms on May 29th, outstanding.

Cheers
Tim M0AFJ
IO70ic

Mark, EI3KD said...

Unfortunately I was QRT for the period around this more northerly opening opening, but I did catch an interesting one on 16th June during which I copied several UA6 stations on 2m, up to 3650km distant (from IO51vw). Here is an extract from my FT8 decodes:

20200616_060700 -21 0.3 866 ~ CQ UC6A KN84 <---- KN84pv, 3398km
20200616_060730 -15 0.3 865 ~ CQ UC6A KN84
20200616_061200 -11 0.5 705 ~ CQ SQ9IVD KN09
20200616_061330 -14 0.2 1397 ~ EI3KD UX2SB -18
20200616_061330 -12 0.1 724 ~ YO6OBK UW8SM KN28
20200616_065200 -5 0.3 1562 ~ OE5JFL RZ6DD -18 <---- LN04mx, 3650km
20200616_065400 -19 0.2 1126 ~ CQ OK1VOF JN89
20200616_065430 -11 0.4 1800 ~ US5FZ RA6C -12 <---- KN94gt, 3489km
20200616_065430 -20 0.2 1126 ~ CQ OK1VOF JN89
20200616_065800 -22 0.0 1486 ~ CQ RX6DN KN94
20200616_065930 -26 0.1 1485 ~ EI3KD RX6DN R-07 <---- but n/c
20200616_070330 -11 0.3 1088 ~ CQ 9A2RI JN65
20200616_070400 -7 0.3 1089 ~ CQ 9A2RI JN65
20200616_070430 -22 0.2 1090 ~ CQ 9A2RI JN65

The interesting thing about that opening was that it was pure Es, i.e. two Es "clouds" in perfect alignment, with some single-hop and some double-hop propagation. This is quite pertinent to the North Atlantic path in the sense that it proves (if it needed proving?) that the distance can be covered via Es alone - useful because tropo on that path is likely to be extremely rare.

There is plenty of 2m traffic in Europe, in suitable locations - I think a lack of dedicated activity at the right locations on the NA side means nothing is likely to happen for the time being...

vy 73, Mark EI3KD.