Friday 11th June 2021: There was an interesting opening on 28 MHz on the morning of the 11th of June between Europe and Alaska. This is pretty unusual at this point of the sunspot cycle and especially during the Summer months.
The map above shows the signal paths to KL2R in Alaska. As the signals between Europe and Alaska pass near the Geomagnetic North Pole, they are often distorted with an auroral tone to the signals. It's suprising to see FT8 digital signals get through.
I guess there's always a chance that the station is a pirate but it does seem to be hearing both Europe and Japan on 28 MHz and there is nothing from the USA.
I heard the German Icebreaker station DP0POL several times on WSPR today on 28 MHz and that ship is currently just west of Svalbard. The distance is about 3000kms so there is something going on to the north on 28 MHz.
I have included a list of the stations heard by KL2R in Alaska below. You can check the times and see if the path opens again. It would be really interesting to see more reports of Alaskan stations on 28 MHz.
Thursday 10th June 2021: In this second of three posts, we will look at some of the extraordinary paths on 144 MHz that were in excess of 3000kms in length. In the previous post, I looked at the paths from the Canary and Madeira Islands to Europe, this time we'll look at the paths from Israel & Lebanon to western Europe.
This is another long post so scroll down. At the end, I'll have a look at some of the evidence for what type of propagation was responsible.
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OD5KU in Lebanon had two paths on 144 MHz to Portugal which were over 4000kms in length.
This map are the FT8 paths that were open on 144 MHz and I'll note a few things.
1) Notice how there is no path from Lebanon to Greece. This suggests that the eastern half of the path was via a single Sporadic-E hop.
2) There are plenty of stations clustered around the south of Italy and Sicily showing where the first hop landed.
3) The western limit of the path was not on the east coast of the Iberian Peninsula but at the far western side on the coast of Portugal. This suggests another Sporadic-E at the western half of the 4000km path.
4) Back on the 28th of June 1979, CT1WW in Portugal worked OD5MR in Lebanon on SSB on 144 MHz for what was claimed to be a double hop Sporadic-E contact. That was an IARU Region 1 record for many years. It looks as if the conditions on the 10th of June 2021 were similar.
To have a complete record, here are some of the long FT8 paths from OD5KU...
Thursday 10th June 2021: This was a pretty remarkable day in Europe for long distance 3000km plus openings on the 144 MHz band. There is a LOT of information so I will split it up into three posts.
This post is the first one of three.
This is a long report so scroll down to see the individual stations from the Canary Islands and the Madeira Islands. I'll put a propagation analysis at the bottom but it seems that depending on where the European stations were located, it was a mixture of tropo only, Sporadic-E & tropo and probably double-hop Sporadic-E / chordal hop Sp-E.
* * *
I'll start with EA8JK as he had the most impressive map from the PSK Reporter website.
There are an amazing eight paths that were in excess of 4000kms! This is well beyond the normal 2300km or so one-hop Sporadic-E limit.
Here are the FT8 paths for EA8JK and just look at how many stations that were in excess of 3000kms.
What is VOACAP?:VOACAP(Voice of America Coverage Analysis Program) is a popular and free professional high-frequency (HF) propagation prediction software tool originally developed for the Voice of America (VOA).
Video Introduction: As part of the 2021 virtual Four Days in May (FDIM) event, Tim Snodgrass KC0DN made a presentation about the accuracy and limitations of the VOACAP programme. KC0DN along with Charley, KC0CD and Mike, AC0HB set up an extensive listening station to monitor the signals from the time standard stations WWV, WWVH and CHU.
The experiment which ran from November 2020 to February 2021 monitored all three time standard stations on a wide range of frequencies from 2.5 MHz to 25 MHz and compared the reception results against what was predicted by VOACAP.
The receive station was set up in Cedar Falls, Iowa while the time standard stations are in Fort Collins, Colorado / Ottawa, Canada & Kauai, Hawaii.
WWV Ft. Collins Colorado: Transmitting 10KW on 5, 10, 15MHz; 2.5KW on 2.5, 20 & 25MHz WWVH Kekaha, Kauai (Hawaii): Transmitting 5KW on 2.5MHz & 10KW on 5, 10, 15MHz CHU Ottawa, Ontario, Canada: 3 kW on 3.33MHz, 5KW on 14.67 MHz, & 7.85 MHz
The presentation is aimed at a US audience as it uses it uses outdated MILES for distances which mean very little for an international audience.
I have prepared a map shown below which shows the distances in kms which makes things clearer as you watch the video.
The presentation which is 45 minutes long can be seen below…
Presentation notes in PDF format can be found HERE
Findings: My own summary of the findings...
1) Like any propagation software tool, VOACAP suggests what the conditions might be like and what paths might be possible. It shouldn't be taken as fact.
2) VOACAP predictions can be too pessimistic.
3) Openings on the higher HF bands (14 MHz and above) happen more often than VOACAP predicts.
4) Lower frequencies like say 80m & 60m are underrated. They can be used 24 hours a day with modern digital techniques.
5) The 30m band is often open at night when VOACAP says it should be closed.
6) The 5 MHz band (60m) was nearly always open 24 hours a day over a 1600km path.
7) By using two bands e.g. 3.5 OR 5 MHz AND the 10 MHz band, a reliable link can be maintained over a 1600km path.
8) KC0DN advocates the use of two bands for the use of 'Store & Forward' digital traffic.
9) Circular polarization on HF can result in a significant advantage.
In Conclusion: This video by KC0DN is the summary of a significant amount of work and should be of interest to anyone with an interest in propagation on the HF bands. It's a bit unfortunate that it uses the title "Breaking Free of the Solar Cycle" on YouTube as that really doesn't describe to the casual observer what the video is about.
It should be remembered that the results are for someone in the United States and at a particular latitude. The results may not apply so readily to say someone at a more northerly latitude.
However, there is still plenty of material in the video of interest and it's worth watching.
There may have been more paths open but I only have the spots on the cluster to go off. Unfortunately the data on the PSK Reporter website disappears after 24 hours.
Propagation Mode: The tropo prediction map below from F5LEN shows the suggested conditions at the time...
It seems likely that it was a combined Sporadic-E / Tropo ducting path. There was a Sporadic-E opening at the time between Italy and Spain so that confirms the north-eastern 1500-2000kms of the path. The south-western part of the path was probably via a marine tropo duct to the Canary Islands.
There were reports of 2700km tropo openings from the Canary Islands up to the south coast of Ireland & England on that morning and the previous morning so those conditions were very good.
There is always the possibility that the path from the Canary Islands to Italy was via double hop / chordal hop Sporadic-E but the probably of that is much lower than a combined Sp-E / tropo path.
D4 Cape Verde: Unfortunately the D4VHF station on 144 MHz is off air at present. If they had been on the air then there would be a possibility of paths well in excess of 4000kms.
1) Thanks to Zvonko, 9A2AE for the following information. At 12:55UTC, there was a 3567 km path open from 9A2AE in Croatia to EA8AIN in the Canary Islands (IL18CQ).
2) Thanks to Davor, 9A5BWW for the following info. At 12:49 UTC, there was a 3468 km path open from 9A5BWW to EA8CSB(IL18TL).
3) Thanks to César, EA8CXN for the following info. He writes..."It was a mix between tropo and ES. Due to mountains on my direct path, I beam my antennas to the opposite direction, bouncing my signal off the 'El Teide volcano".
Log extract from the 7th with the TR+ES opening... 07/06/21IV3GTHFT8+13-122mItalyEA8CXN (~3255kms) 07/06/21S52LMFT8+13-122mSloveniaEA8CXN (~3255kms) 07/06/21IV3/HB9CATFT8+07-052mItalyEA8CXN (3264kms) 07/06/21IU4FNOFT8-14-172mItalyEA8CXN (~2997kms) 07/06/21S59FFT8-11-212mSloveniaEA8CXN (3273kms)
On the 3rd of June, I was on the 40 MHz band listening for the new EI1CAH beacon in the west of Ireland when I noticed some very distinctive static crashes. When I checked the rainfall radar map, sure enough there were plenty of lightning strikes just over 100kms from my location.
I was surprised just how strong they were considering they were so far away.
It's worth getting to know that these sound like as they give you plenty of time to unplug your antennas before the lightning reaches your location.
5th June 2021: Just as European stations are currently experiencing multi-hop openings on 50 MHz to Japan & China, stations in North America are experiencing similar openings to the Middle East.
Chris, VO1CH in Newfoundland sent on an interesting example of this with his 50 MHz FT8 contact to 9K2OW in Kuwait, a distance of approximately 8376kms.
Chris reports other contacts with OD5ET in Lebanon and 4Z1UF in Israel at around the same time... i.e. 13:00 UTC.
As the screen shot below shows, the contact with 9K2OW was down around -20dB which is well below what is audible to the human ear. It's a nice example of how the digital FT8 mode opens up paths which would be impossible on SSB or CW.
Almost but not quite: On the 5th of June 2021, Stamen LZ1KU in Bulgaria and Oleg A65BR in the United Arab Emirates almost managed to complete a FT8 contact on 144 MHz over a distance of 3,280kms.
While both stations managed to get some successful decodes, they were unable to complete a contact on this occasion.
The composite screen above from LZ1KU shows a decoded FT8 signal from A65BR at -20dB. An earlier decode at 14:48 UTC was at -16dB. The exchange shows A65BR giving a signal of -13dB for LZ1KU.
2021-06-05 14:48:58Z LZ1KU Stamen FT8 144445 -16 dB 0.3 s Freq 1369 Hz > CQ A65BR LL75
In the examples above, the FT8 signal would have been below what is really audible to the human ear so a contact on CW would have been very unlikely.
A65BR also spotted LZ1KU on the DX-Cluster...
Spotter Freq. DX Time Info Country A65BR 144174 LZ1KU 14:37 05 Jun 21 LL75SL<ES>KN32AH CQ HRD Bulgaria
LZ1KU was reported to be using 'full power' to 4 x 12-element Yagi array while A65BR was using 50-watts to a 7-element.
Amazingly, IZ7AUH in the south of Italy also managed to get a decode from A65BR over a distance of almost 3,900kms.
Propagation Mode: Both paths were well in excess of the 2300kms or so we might expect from one hop Sporadic-E so how can we explain it?
The tropo prediction map from Pascal, F5LEN shows some excellent conditions in the Arabian Gulf so it is probably no great suprise that the 3000km+ paths were in that direction.
One scenario is that there was a tropo duct over the Arabian Sea and this then coupled into a single hop Sporadic-E opening to Bulgaria. For the Italian station, it would require another few hundred kms of tropo at the western end of the circuit to complete the path.
Another scenario was that it was Chordal Hop Sporadic-E with the 144 MHz signal bouncing off two Sp-E clouds that were in just the right location. There was an extensive Sporadic-E opening from Israel into Europe so the MUF was high in the region.
And just to add another variable into the mix, the International Space Station was around at the same time (or at least I think it was based on an observer in Ankara).
It's hard to know for sure what the exact propagation mode was. It's a bit like a science experiment and we have just two data points. It's easy to make assumptions but we just don't know.
For me, the main thing is that it is yet another example of a 3000km+ path on the 144 MHz band.
This will probably be my last post about the openings on 50 MHz between the north of Australia and Europe. Even though 15,000kms is a remarkable distance for 50 MHz near the bottom of the sunspot cycle and it may be a big deal for individual stations in Europe to work Australia, my interest is in the mode of propagation.
For the last few days, I've collected as much data as I could about these 6m Australia to Europe openings so that there is some sort of record online about them. Considering that they are now happening almost daily at present, I think the chances of them being solely due to multi-hop Spoardic-E is near zero. I don't believe it's possible to get 7-8 Sporadic-E hops at 50 MHz in the same direction day after day after day.
I'll keep a watch out for 50 MHz openings from Europe to the VK2/VK3 region which is the south-east of Australia as these are the exceptional openings at this stage.
Friday 4th June 2021: The map above shows the paths from VK4ABW in Darwin to Europe.
A list of the paths from European stations to Australia is shown below...
Thursday 3rd June 2021: There was a remarkable opening on the 3rd of June from the Azores in the North Atlantic to Europe with paths in excess of 3,000kms being recorded.
The FT8 map above from the PSK Reporter website for CU3EQ in the Azores with a cluster of reports out around the 3000km mark in Belgium, the Netherlands and Germany. A full list of stations is shown at the bottom of this post.
This is the map for CU3AA which has a similar pattern...
And this is the map for CU1AL...
For all three CU stations, paths in excess of 3000kms were open to Germany on 144 MHz.
Propagation Mode:As reported by stations on the DX Cluster, the primary propagation mode was Sporadic-E. However as the maximum range for one hop is in the region of 2300kms, something else had to make up the additional 700 or so kms.
There are two possibilities.
One was Chordal Hop Sp-E with a bounce going from Sp-E to Sp-E cloud. This would however require two intense areas of Sporadic-E at just the right spot to support 144 MHz propagation.
The more likely scenario was that it was one Sporadic-E with a tropo extension. The weather charts show high pressure over the Azores...
The tropo forecast from the website of Pascal, F5LEN suggests that a few hundred kms of tropo around the Azores might be possible.
The Sporadic-E prediction map from Jim, G3YLA shows a kink in the Jet Stream to the south of Ireland which may have been a trigger mechanism for the Sporadic-E.
In his daily E's prediction on the PropQuest website, G3YLA wrote... "The sharp upper trough west of the UK is also a good source of atmospheric gravity waves (AGW) and the southerly jet stream from Portugal to Ireland could look good for paths to EA and CT with a possible extension by second hop to EA8/D4."
This region is shown in Purple above and is very close to where the 144 MHz Sporadic-E cloud was located.
Conclusion: It seems likely that the first few hundred kms were via tropo from the Azores and then coupled into a single Sporadic-E hop onwards to Europe.
Trans-Atlantic on 144 MHz??? The map below shows a 3000km circle centred on the Azores...
Considering there was a 3000km opening on 144 MHz between the Azores and Germany on the 3rd of June, sure a 3000km path on 144 MHz from the Azores to North America is possible?
Stations in St.John's, Newfoundland are close to the one hop Sporadic-E range. Stations in Nova Scotia would need a tropo extension.
If the North Atlantic is going to be bridged on 144 MHz then surely Canada to the Azores would be a first step in the process?
Thursday 3rd June 2021: Another day, another 15,000km opening on the 50 MHz band.... well almost. This time the longest opening seen on the PSK Reporter website was the 14,966km path between KG6DX on the island of Guam in the Pacific and EA8DBM on the island of Tenerife in the Canary Islands.
EA8/DF4UE on the neighbouring island of Lanzarote was just 150kms behind.
I checked the PSK Reporter site and there were paths open for both to multiple stations in Japan as well. IF the signals took the direct path then they crossed over the north of Russia.
Wednesday 2nd June 2021: Another day and yet another opening on 50 MHz between Europe and Australia.
The longest path on the day however seems to have been between VK4ABW in Darwin on the north coast of Australia and EA8DBM on the island of Tenerife in the Canaries. The 50 MHz path which was on the FT8 mode works out to be around 16,220kms.
Just to put that in perspective, that's the same distance from Darwin to the Great Lakes in North America.
As the map shows above, the 50 MHz was also open to Europe and it managed to open up to G7RAU in the far south-west of England as well.
Mode of Propagation: The 50 MHz band has been open between Europe and Australia for four of the last fives days. Whatever the mode of propagation is, the simple 'it must be multi-hop Sporadic-E' is probably not the full explanation.
It would be interesting to know if European stations working Japan, China and Australia are experiencing any skewed paths or is everything on the correct beam heading?
Tuesday 1st June 2021: Over the last week or more, there have been openings from Europe to Japan on 50 MHz with distances in the region of 9,000kms. There was an interesting opening on the 1st of June however from Europe to the island of Guam in the Pacific.
The map above from the PSK Reporter website shows the paths that were open for KG6DX on Guam with maximum distances in the region of 12,000kms.
From a European perspective, a contact with a station out in the Pacific would be considered really good for say down on the HF bands but it's pretty amazing for 50 MHz, a VHF band.
When I checked the PSK Reporter website, I had a quick look at the last FT8 signal reports for the stations in Europe and they were generally down in the -10 to -20dB region. It looks as if maybe one or two might have possibly made a very weak CW contact while SSB would have been impossible.
That assumption is based on the available data which is limited but it does suggest that the opening was marginal.
The opening to Europe seems to have been from roughly 05:40 to 07:00 UTC.
Propagation Mode: The interesting thing about this 12,000km opening is that because everything is north of the equator, we can rule out TEP (Trans-Equatorial Propagation). If it was multi-hop Sporadic-E then it may have been 6 hops or so.
For something so 'sporadic', these multi-hop openings seem to be happening a lot.
The paths from stations in Europe to Guam are shown below...
Tuesday 1st June 2021: Yet another opening on 50 MHz from Australia to Europe but this one was perhaps not as good as previous days.
Update: Roger, VK3FZ reports that he made a successful contact with OZ3K in Denmark. VK3FZ to OZ3K on 50.315283 in FT8 at 2021-06-01 05:42:00Z (OZ: Denmark) Sent -21, Received -15 Antenna: 6-element LFA Yagi
Propagation Mode: We're back to the same question again... How do 50 MHz signals from Europe reach Australia near the bottom of the sunspot cycle?
The easy 'go to' answer was that it was multi-hop Sporadic-E, case closed.
The problem I'm starting to have with this is down to probabilities.
Take SP4K in Poland. What are the chances of one hop Sp-E in the direction of Australia capable of supporting a 50 MHz signal? It's late May, it's the Summer Sp-E season so it's pretty high.
Two hops?... What is the probability of getting two Sp-E regions spaced at just the right distance to allow a double hop at 50MHz? The probability is obviously lower.
Follow that same logic and apply it to 3 hops, 4 hops and so on. By the time we get to 15,459kms, we're probably looking at 8 hops.
What is the probability of getting eight Sporadic-E clouds capable of supporting 50 MHz spaced at just the right distance from each other... all the way from Europe to Australia?
And if that probability wasn't low enough, what then is the probability of 8 hop Sp-E on 50 MHz from Europe to Australia on two out of three days?
I think the probability is now so low that there must be some other answer. Perhaps TEP (Trans-Equatorial Propagation) from Australia to China accounts for a large part of it? Some other propagation mode?
I'm not sure the simple 'It must be multi-hop Sporadic-E' adds up anymore.
It looks as if there was a successful FT8 contact between VK4CZ in Australia and SP3MM in Poland, a distance of about 15564kms. The signals seem to have been quiet weak and were in the range of -16dB to -20dB which is below what is audible to the human ear i.e. a cw contact would not have been possible.
As for the propagation mode, it seems likely it was multi-hop Sporadic-E with possibly eight hops required. I say 'likely' as I sometimes wonder what are the chances of getting eight Sp-E hops in a row at 50 MHz.
We still have all of June to go yet so there could be more openings on 50 MHz from Europe to Australia.
Friday 28th May 2021: I left the radio monitoring the WSPR frequency on 28 MHz for whole day and I heard signals from all over Europe including DP0POL on the German Icebreaker ship near the north of Norway.
At the end of the day, I got an interesting e-mail from Andreas, DL2KCL about my reception of his very low power WSPR beacon during the day.
Andreas wrote... "You received a transmission from my homemade WSPR-TX on 10m. The TX puts out 10 mW directly from a Si5351A-chip. No PA. It runs from a single rechargeable D-cell with a DC/DC-converter (85 mA).
The antenna is a piece of about 2.5 m thin wire wound on a 18 cm PVC tube in resonance on 28.2 MHz. There is no additional counterpoise."
I checked back through the WSPR logs and amazingly, I had heard the 10-milliwatt signal from DL2KCL a total of 77 times during the day. The weakest signal was -27dB which is buried way in the noise. The strongest signal was -12dB which would have been just about audible to the human ear.
The photo above shows the transmit antenna which is just a quarter wave of wire wound on an 18cm PVC pipe. To hear such a low power system 77 times during the way just goes to show how good conditions must have been.
On my side, I was just using a simple CB type half wave vertical so there was no additional gain to pull in weak signals.
Analysis: The one crucial part of equation is the distance... 1075kms. During the Sporadic-E season, signals in the 1000 to 1500km range are a bit like the sweet spot on 28 MHz.
There are a lot more openings on 28 MHz compared to the higher bands like 50 MHz and signals around 1100kms are at the very least 6dB stronger than those out around 2200kms just due to the fact they are closer.
The signals at 1100kms are also coming in around 8 degrees above the horizon which allows it to clear local obstructions at either end of the path.
Antennas on 28 MHz will probably have more gain at 8 degrees above the horizon in comparison to say 1 or 2 degrees and a 2000km skip distance.
It just goes to show how good the 28 MHz band can be when the conditions are right.
In response to a recent query, one of the D4VHF team has confirmed that their 144 MHz VHF station is off air at present.
Andrea, HB9DUR writes... “I am sorry to disappoint you re. D4VHF but the station is not fully operative, especially on 2m.
Monteverde has been suffering from non stop high winds from Christmas last year till some weeks ago.
So the yagi to west is heavily damaged by strong winds, the towers as well are not in a good shape. Moreover no power amplifier is available until somebody can travel there….“
The D4VHF station on Cape Verde off the west coast of Africa has in recent years has been responsible for some of the most spectacular contacts on 144 MHz and 432 MHz to Europe and across the Atlantic to the Caribbean.
For the moment (May 2021), they are still active on 50 MHz and the QO-100 satellite.
25th May 2021: A little bit of history was made on the 40 MHz band on the 25th of May when the first contact between two stations in Croatia took place.
At 06:00 UTC, Patrik, 9A5CW and Zeljko, 9A2EY completed a successful FT8 contact on 40.680 MHz.
The distance was 24.5kms between the two stations over an obstructed path and both stations were using vertical non-resonant HF antennas.
One of the antennas was a vertical for the 60m HF band without a tuner and the radio was an ICOM IC706 Mk2.
Hopefully this will encourage more 9A stations to experiment with the band.
Tuesday 25th May 2021: During the major Sporadic-E opening on the 25th, many European stations made multiple contacts on the 144 MHz band. While the vast majority were in the one-hop range (<2300kms), there were a few exceptional contacts.
Jan, 4X/OM2IB in Israel (KM72JC) managed to complete two FT8 contacts with two stations in Germany during a short opening.
The two German stations were DJ9MG(08:18UTC - JO52TC - 2909kms) and DG6JF/P(08:31 - JO33QN - 3234kms).
The FT8 screen from 4X/OM2IB is shown below...
It clearly shows the two FT8 contacts as well as reception of PA0O and DL7TY. The time range of the reports is from 07:53 to 08:36 UTC, a span of roughly 43 minutes.
Propagation Mode: As outlined already, the normal maximum distance for one-hop Sporadic-E is about 2300kms. There are probably two choices to help explain how 144 MHz signals from Germany traveled the approximately 3000kms to Israel.
Theory 1) Sp-E & Tropo: In this scenario, there was one hop Sporadic-E from Germany to Turkey and then the last few hundred kms by tropo ducting over the sea to Israel. The tropo prediction map below from F5LEN certainly suggests that this might be possible.
The distance from 4X/OM2IB to the coast of Turkey is about 700kms.
In this scenario, it's not hard to imagine a Sporadic-E hop of 2200kms going from DJ9MG is the eastern half of Germany to the southern coast of Turkey and from there via a tropo duct of about 700kms to Israel.
The problem however comes with DG6JF/P who is an additional 300kms further away at 3234kms. That can't be easily explained by a tropo extension at the eastern end of the circuit as that would require the duct to cross over a large part of the landmass of Turkey. .
It's possible that the Sporadic-E ionised region was higher than usual which sometime happens near the start of an opening but it seems a bit of a stretch.
Theory 2) Chordal Hop: The other possibility is that there were two active Sporadic-E regions involved and the signal bounced from one to the other before returning to the ground. This resulted in a range in excess of 3000kms.
The problem with the Chordal Hop theory is that it requires two Sporadic-E clouds to line up correctly. It would seem that it does happen at 144 MHz but how often and for how long?
In conclusion: In his Sporadic-E report, 4X/OM2IB noted..."Random and very short openings. Probably sea TROPO + Es for this distance. Doesn't look like a double Es hop."
Sometimes when you can look back at an opening, you can examine the evidence and you can determine the most likely scenario. In this 144 MHz opening between Germany and Israel, it's hard to know for sure which propagation mode was responsible. I think without further evidence, we just have to put a question mark next to it.
It does however show yet again that contacts in the region of 3000 kms are possible at 144 MHz, the same distance across the North Atlantic from Newfoundland to Ireland.
Addendum:
1) PA0O in his blog post says he worked Istanbul in Turkey at 2150kms. This gives some additional credence to the Sp-E & Tropo theory. Link HERE
