There was a weak Sporadic-E opening on 28 MHz on Thursday the 8th of April 2021 with a total of 20 stations heard on FT8.
Some of the Spanish signals were actually audible and weren't just buried in the noise. I tried two scans of band when the FT8 signals were audible but I failed to hear any of the beacons.
In another two weeks time around the 23rd of April, there should be some decent openings on 10m.
The solar flux today was just 76.
Foreword... AIS (Automatic Identification System) is used by ships to identify their location by sending out a signal at 162 MHz which is pocked up by other ships and shore stations. There is a growing community of enthusiasts near coasts around the world who monitor these signals and feed the decoded signals into websites that then display the positions. AIS signals which are a few watts in power act like beacons and can be used by radio amateurs to show if there is any tropospheric enhancement on the VHF bands... de John, EI7GL
Propagation Monitoring 2m Band with AIS Data from Vesseltracker.com ...by Jörg, DM4DL
For 5 years I was able to inspire some HAM radio operators and meanwhile a partnership between the company Vesseltracker and Gabriel, EA6VQ, the operator of DXMaps is planned.
As a test, the Vesseltracker data of some AIS-RX are already being forwarded to DXMaps.
Please check whether you would like to participate in the community with your location?
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| Example of enhanced VHF conditions in the eastern Mediterranean |
The equipment is provided free of charge by Vesseltracker, you can read more here: www.vesseltracker.com/en/community
You are invited to contact David Hewson, the antenna manager in your native language via the Vesseltracker community page, David is from Canada.
Now we are waiting for good conditions, which can be seen in DXMaps under AIS.
VY73 Jörg DM4DL
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| Example of enhanced VHF conditions |
Previously I used the page for DMR information in Ireland. The new 'Digital' page has links to all of my previous posts that contained any sort of radio related digital information.
Some of the areas covered are...
Digital modes for broadcasting like DAB, DAB+ and DRM
Weak signal modes like FT8, FT8, PI4 and FreeDV.
Modes like DMR and C4FM.
The new page is HERE
The small company which is based in Manchester in the UK has just announced that it has closed due to the owner having health issues.
Frank, VO1HP reports that the VO1FN 144 MHz Trans-Atlantic monitoring station will be reactivated by the end of May 2021!
This SDR receiver will be using SDR Console V3 and WSJT-x and will report to the PSK Reporter website as VO1FN.
The station will be located in St.John's, Newfoundland and will use two stacked 5-element 144 MHz LFA-Q quad style Yagis from Innovantennas.
The antennas will be pointing at western Europe and the receiver will be listening on 144.174 MHz which is the FT8 frequency.
Trans-Atlantic on 144 MHz: Is it possible??? ...As can be seen from the map above, the distance across the North Atlantic between Newfoundland and Ireland is just over 3000kms. This is well beyond the normal 2300km or so range for normal Sporadic-E or meteor scatter and it seems unlikely that it would be spanned a marine tropo duct going all of the ways across.
I emphasize the work unlikely but it's not impossible. The North Atlantic is not noted for its fine calm weather and there is nearly always some low pressure system in there stirring things up.
What is likely to happen a lot more often are shorter ducts that are in the region of 1000kms in length and these could happen at either end although the eastern end seems more likely. If there is a Sporadic-E opening or a major meteor shower at the same time as a good 1000km marine duct then it may well be possible.
It seems to me that the path from Newfoundland to the north-west coast of Spain as the most likely one even if it is a bit further away. The number of stable marine ducts in that part of the Atlantic are higher than further north closer to Ireland.
Updates... More news as it comes in!
Links...
If you're on Twitter then you can follow me at https://twitter.com/ei7gl
According to the tropo forecast website of F5LEN, there is a chance of enhanced tropo conditions across the North Atlantic on the weekend of Saturday 3rd & Sunday 4th of April 2021.
While contacts at 144 MHz are probably unlikely, any suitably equipped stations in Ireland, the UK, France, Spain & Portugal might be interested in trying.
Frank, VO1HP reports that the following stations will be monitoring from Newfoundland mainly on the FT8 frequency of 144.174 MHz...
VO1IV Aaron - St.Johns Newfoundland - (10el yagi, FT991, 50w) - 144.174 MHz FT8
VO1DZA Graham - St.Johns Newfoundland
VO1WEB Matt - St.Johns Newfoundland
The distance across the North Atlantic is in excess of 3000kms and has yet to be bridged on 144 MHz.
* * *
Frank also reports that they plan to get their SDR Transatlantic Beacon Receiver site operational in May of 2021 when the antennas are taken out of storage.
Links...
1) F5LEN tropo prediction website
In this three part series of posts, I am going to look at the 2020 logs of a very active Band 2 DXer and what they might suggest about propagation on the 88 to 108 MHz FM band. The posts are broken up into three parts... 1) Tropospheric Propagation, 2) Sporadic-E & 3) Meteor Scatter.
First off, a big thank you to Paul Logan who very kindly shared his 2020 Band 2 logbook with me and answered numerous questions that I had. Outside of his usual 'local' FM radio stations which he can hear under flat conditions, he logged and identified roughly 5,500 long distance signals on Band 2 in the year 2020.
Profile of Paul Logan... Paul is a very active listener of Band 2 radio (88-108 MHz) signals and has been logging stations that he has heard for about 30 years. He lives in Lisnaskea in Co.Fermanagh in Ireland and his location is shown in the map below.
Paul's location is far from ideal for listening to distant VHF signals. He has some local hills to the east as well as the hills and mountains in Scotland, England and Wales as a further obstruction.
Equipment... For the 2020 logs, Paul used an SDRPlay RSP1 & RSP1A.
In recent years, software defined receivers have transformed FMDX listening as signals can now be seen on a computer screen as well as being heard. This allows a user to visually check for any unusual signals and can then go investigate it. One of the most impressive features is the ability to record sections of the spectrum and a user can then go back later to listen for anything unusual.
For an antenna, Paul is using a Korner FM9 from Antennenland in Germany.
This antenna which is mounted 8 metres above ground level is highly regarded by many FMDXers in Europe.
2020 Tropo Log... During the year 2020, Paul heard and identified around 86 signals that were heard via tropospheric propagation. This mode of propagation occurs when signals are bent over the horizon by sharp changes between air layers with different temperatures and moisture content.
I have picked out 5 groups of signals of note which I have marked from A to E. Refer to the map below and then the horizon profile further down.
A - This group of signals from the north-west corner of Spain are in the region of 1200 to 1300 kms. The sea path from the south coast of Ireland to the north coast of Spain is very good for VHF propagation with marine ducting happening several times a year. These sea paths are usually the best for very long paths in excess of 500kms and sometimes the signals can be amazingly strong.
In the video below, Paul shows how he was able to hear a Spanish radio station on a small portable radio when the opening was at its strongest. With his main directional antenna, he was able to hear the Spanish signals for most of the day.
In the horizon plot below, you can see that the path to NW Spain at Paul's location is largely unobstructed with only a 1 degree elevation. This allows very low angle signals to arrive at his location.
B - This path to Brittany and Cornwall is similar in that the sea path helps and the hills on the horizon are quite low at about 1 degree elevation.
C - This interesting batch of signals came from Norfolk in the east of England, a distance of 600kms. These signals had a few obstacles to overcome including Paul's local hills as well as the Pennines running down the centre of England.
With the signals arriving at least 3.5 degrees above the horizon, the means of propagation may have been via an elevated duct in the region of 500m to 2000m above the earth's surface. While higher frequency VHF & UHF signals tend to propagate better inside of ducts, it went as low as 89.7 MHz in this example.
D - This cluster of signals from the Netherlands and Germany were interesting for a number of reasons. First off is the sheer distance... about 1000kms which is unusual for Band 2 tropo. I suspect that the sea path over the North Sea may have helped for a large part of the journey.
If you examine the horizon plot below, you'll notice that there is a gap in the hills due east (90 degrees) where the horizon has an elevation of about 2.5 degrees.
What's really interesting is that the paths from the four transmission sites fit exactly in the gap. The signal from the most northerly German transmitter is exactly at the left hand side of the gap. The signal from the most southerly Dutch transmitter is exactly at the right hand side of the gap. The four signals fit exactly like a glove which suggests that they are coming in just barely above 2.5 degrees above the horizon.
E - These signals from the Newcastle area were at a distance of about 370kms and again are coming in from an obstructed path. This one has the highest angle as it had to clear a local hill that was 4 degrees on the horizon.
There was a modest opening via F2 propagation on 28 MHz on Wednesday the 31st of March 2021 with Israel, South Africa, Mauritius in the Indian Ocean, Brazil & Uruguay.
Sometimes with FT8, my PC is decoding signals that I can't hear but some of these were very audible. I checked the beacon band and I heard the ZS6WAB beacon on 28.2048 MHz at about 419.
The solar flux was up to 80 today, a jump of 4 on yesterday.
There also seemed to be a weak opening to Europe with some UK stations making it through on what seemed like weak short skip.
One signal of interest was that of EI2CN who was -6dB even though he is 250kms distant. I noticed that BBC4 radio was coming in from Wales on 104.9 MHz earlier this morning so there was some tropo about. Was there tropo on 28 MHz as well? It seems like it.
List of stations heard over 3000kms...
The shutdown is scheduled for today the 31st of March.
During a visit to a local ALDI store on Monday, I noticed that they are now selling DAB radios are part of their 'Special Buys'.
These went on sale in Ireland on the 28th of March with the DAB network shutting down three days later.
Now in fairness to ALDI, these radios also have FM so they're not completely useless but it does have DAB radio in large letters across the front of the box.
These radios are probably produced mainly for the UK market and they just happen to be part of the offering in Ireland as well. This 'Special Buy' offering was also probably planned months in advance and the decision to manufacture, import and sell the radios was made months in advance of the decision by RTE to close the DAB network.
I just thought it was ironic that they started selling a digital radio on a Sunday and the digital radio network was closing down the following Wednesday.
There was a weak Sporadic-E opening on 28 MHz to the south of Spain for about two hours on the evening of the 30th of March 2021. While many of the signals were audible, they were quite weak.
I did have a listen around the beacon part of the band at one stage but I couldn't hear anything.
The Falklands and St Helena was also heard...
As we move towards mid-April, we should start seeing more Sporadic-E openings on 28 MHz with stronger signals.
For a low power radio, the amount of hype and buzz surrounding it has been amazing. There has been a host of online reviews, blog posts and videos about it but they tended really only to concentrate on the radios features rather than its performance.
In addition, I think it's fair to say that a lot of the reviews were done by HF operators. I saw one person doing a frequency stability test on WSPR on 20m (14 MHz) which was frankly useless as it meant nothing. Frequency tests need to be done at the highest operating frequency on the radio i.e. 432 MHz where the changes would be the biggest.
RadCom Review... In the April edition of RadCom magazine, a full review was carried out by Peter Hart, G3SJX. Peter carries out extensive performance tests of radios on his bench on a regular basis and his reviews are highly regarded as they're seen to be truthful and honest. If there is a problem or issue with a radio then he calls it out for people to see.
The review is quite extensive running to five pages but I noted that he mentioned some 'low level intermodulation products' appearing with some 'quite small input signals' on the VHF bands. Whether you'd notice these or not I guess might depend on how RF quiet your location is.
One of the big questions that VHF operators had about this radio was about its frequency stability. The previous IC-9700 was known to drift and many VHF guys had to add third-party GPS locked frequency standards to overcome this. Would the IC-705 have the same issue?
When the IC-705 was introduced, it was mentioned that it had a built in antenna for GPS and some people speculated that the frequency stability might be GPS locked as a result.
Peter confirms in his review that the IC-705 uses a high stability temperature controlled crystal oscillator to achieve a performance of 0.5 parts per million (PPM). The built in GPS is as far as I know just there primarily for D-Star operation in terms of timing and location.
I did however come across a YouTube video today from Hayden, VK7HH who did a frequency test on 432 MHz with WSPR.
While the IC-705 did drift 2Hz over the two minute transmission, it did stay within the required 4Hz window for the mode.
In Conclusion... In his final summary, Peter G3SJX concludes..."The IC-705 is a great take-anywhere QRP radio, ideal for all outdoor activities and SOTA expeditions. Covering HF through to the UHF bands with all-mode operation, a top-level performance and extensive remote connection capabilities, it is quite a remarkable piece of kit. Currently priced at £1300, it is excellent value for money."
It might be outside the price range for some but it looks that it's a great radio for those who can afford it.
RadCom... RadCom is the journal of the Radio Society of Great Britain and is posted out on a monthly basis to all members. A digital version is also available on their website for members to view and each issue stays there for 12-months.
The RSGB website can be found at https://rsgb.org/main/
Addendum: Snippet from the review done in QST magazine...
The data is taken from the almost 1.8 million QSO's logged on the site in the last 13-months.
This is bound to stir some controversy with a lot of people having misgivings about how this digital mode seems to be replacing the traditional SSB and CW means of communication.
As can be seen from this previous post, FT8 has enjoyed an explosion in popularity since it was released in 2017.
It does look though as if the pendulum have swung a bit too far in the digital direction. During the Summer Sporadic-E season, there are many times where signals are reasonably strong and a SSB contact could be completed in a much shorter time frame than say a FT8 contact with its 15-second transmission cycles going back and forth.
How to get more of a balance though might be easier said than done.
Links...
1) G7VJR Blog
The latest stats from the Clublog website suggests that the FT8 digital mode now accounts for over half of all contacts made on the amateur radio bands in the year 2020.
The chart below from July 2017 to March 2021 shows how FT8 has grown to dominate the bands since its release in the second half of 2017.
Surprisingly, the newer and faster FT4 mode doesn't seem to have made any inroads on the popularity of FT8 since its introduction in late 2019.
Tens of thousands of logs are uploaded to the Clublog website every year and the data trends for 2020 are based on over 66.4 million contacts.
Links...
Back in the middle of March 2021, I reported in a previous blog post how F0FYF in the east of France had heard a beacon on 144 MHz that was using the same callsign as the ZD7GWM beacon on St Helena in the South Atlantic.
After listening to various recordings, I was able to confirm that the signal heard by F0FYF was different from the real one.
Now, there is a report that the beacon has been heard by someone else in France but on a completely different beam heading.
Someone left a comment on the blog of Jeff, F0FYF to say that they had heard the bogus ZD7 beacon on 144.475 MHz as well! This person said that he was in the south of Perpignan and that the 'beacon' was on a beam heading of 70 degrees from his location. He was using a 7-element Yagi on a 9-metre mast.
F0FYF originally said that he had heard the beacon on a beam heading of 200 degrees. I plotted out these two beam headings and they intersect near Marseilles.
They also said that the beacon is often on air for 90 minutes to 2 hours at a time on a regular basis.
Is it located somewhere inside the circle above?? It would be interesting for some local French radio amateurs to have a listen. Is there an online SDR with 2m in the area?
Links...
There was a hint of the upcoming Sporadic-E season when there was a weak opening on 28 MHz on Friday 26th March 2021. It didn't amount to much though and it seemed mainly confined to Spain.
The previous day, the 25th of March was a bit unusual in that I didn't hear a single FT8 signal on 10m all day. I nearly always hear something.
As we move into early April, the Sporadic-E openings on 28 MHz should start up with maybe more regular openings later in the month.
If you're interested in the upper HF bands or any of the VHF and UHF bands then your horizon is all important. On bands like 144 MHz and above, the vast majority of signals are coming in from the horizon and just above it.
On bands like 28 MHz, 50 MHz & 70 MHz, the signals may be coming in at a slightly higher angle with Sporadic-E but they are still very close to the horizon. Whether you're operating from home or thinking or going portable then knowing your horizon can help explain what's going on.
First off, the website for checking your horizon is https://www.heywhatsthat.com/
In this post, we'll look at how to use it and some tips on getting them most out of it. To help explain it, I am going to do a profile of Paul Logan's location in Lisnaskea in Co.Fermanagh, Ireland. Paul is an avid listener to the Band 2 FM band from 88 to 108 MHz and logs hundreds of radio stations from all over Europe every year.
Getting started...
After going to the HeyWhatsThat site, click on the 'New panorama', zoom in to find your own location on the map and then click on it.
I have done this in the example above for Paul's location and them zoomed back out. On the left side of the screen, your latitude and longitude will be automatically filled in after you click on the map. You can also select the height above ground so I selected 8-metres which is the height of Paul's antenna.
Note that the site uses the general topography to calculate your horizon, it doesn't take buildings or trees into account.
Also make sure to select 'Metric' at the bottom of the screen to use proper measurements.
Then click 'Submit request'.
Using the results...
After a short while, a map is generated. I clicked on the 'Visibility cloak' to show the areas that are visible from Paul's location. The Red triangles are distant peaks and I clicked on 'Contours' to highlight the topography.
This is that the horizon looks like for Paul...
There is a large hill with an elevation of about 5 degrees to the north-east of Paul's location (45 deg bearing) and this is clearly shown on the image above. This would have a major impact on all signals at 144 MHz and above. As Paul notes himself, he finds it very difficult to get distant stations on Band 2 in that direction.
That hill would also impact on all long distance single hop Sporadic-E coming from that direction on all bands from 28 MHz to 144 MHz. Short skip arriving at a higher angles on say 28 MHz or 50 MHz would probably clear the hill.
Due east at 90 degrees, there is an interesting gap which might might allow some distant Band 2 tropo or Sporadic-E through.
From 100 to 140 is another impediment to low angle signals but it gets much better after 150 degrees or so. Paul has a very good take off at about 190 degrees towards the Canary Islands and even those distant line of sight peaks around 270 degrees are so low that there are unlikely to be much of a problem. As a result, his location will be wide open to say the USA on 28 MHz once the sunspot numbers increase.
Example 1: Poor tropo path to Scotland.
In this example, I have shown what the path is like to Scotland and how the hill is in the way. If you are trying this from your location, then just click on any location of interest and the site will show you the path and where it is on your horizon.
Example 2: Good tropo path to Spain
As can be seen from the horizon profile, Paul has a good path to the south and this can allow him to gain access to the marine duct that sometimes occurs between Ireland and Spain. The distance shown is about 1200kms which is really good for Band 2 tropo.
Example 3: Sporadic-E footprints...
Using the 'Up in the air' button, I was able to simulate what the limit for one hop Sporadic-E from Paul's location might be. One the left above is the approximate range if Paul had a completely flat horizon. The one on the right is the reality.
For Italy, the local hill restricts signals further south than Rome.
For Poland, signals from the east of the country should be easy to hear except the local hill makes things more difficult. Belarus and the west of Ukraine are also more difficult. Notice that that little gap at 90 degrees is reflected in the Sporadic-E footprint.
For the Baltic states and Finland, they should be well within Sporadic-E range but again, the local hill makes things difficult.
It's possible in many cases that some local tropo conditions will extend the footprint further east but overall, the local hills make hearing these areas more challenging.
Example 4: F2 propagation...
As the sunspots increase, there will be weak F2 openings on 28 MHz. Towards the west, Paul should have no problems reaching Newfoundland and Nova Scotia in Canada. With the help of a more southerly second hop, he is well placed to hear signals from well into the USA.
Towards the eastern Mediterranean, the local hill will block some of those signals when the band is just open. Ironically, it may actually be easier to hear signals further away in places like the Arabian peninsula once there is a second hop.
'Up in the air' Values...
Example 5: Line of sight paths...
The HeyWhatsThat site can also be used to examine line of site paths. The map above shows the path from Paul's location to Clermont Carn in Co.Louth, about 75kms away. This is a major transmitter site for Irish radio stations.
Let's say for example, Paul wanted to get a line of sight path for a contact on the microwave bands. The profile below shows the local hill in the way but there is a location 7kms away that is line of sight to Clermont Carn.
Other uses... Here's a few...
Portable operation, DX-peditions, Summits on the Air (SOTA) activations, contesting ... are there obstructions in the way? Is your 'perfect' contest location blocked at a low angle on the upper HF bands say to the USA?
In summary... This is a very useful utility to have and the more you use it, you tend to think of other uses.
For the bands like 28 MHz and 50 MHz, short skip can hide the shortcomings you may have in a certain directions. Your horizon profile should make you aware of these and you're looking for no more than 2 degrees.
For the higher bands like 70 MHz, 88 to 108 MHz, 144 MHz and above, tropo becomes a more important propagation mode. This time, you're looking for a very low horizon and the lower the better.
There's a very good reason why people put antennas up as high as possible on the VHF and UHF bands.
This is one of the VHF contacts that caught my attention during the summer last year.
On the 2nd of July 2020, HZ1SK in Saudi Arabia and K4MOG in the USA completed a successful FT8 contact on 50 MHz.
What was unusual about this contact was the fact that it was in the region of 11,460 kms. To put that into context, that is the equivalent of London to Hawaii or London to the NW of Australia.
The propagation mode was probably multi-hop Sporadic-E with at least six hops being required. While single hop or double hop Sporadic-E is reasonably common, the chances of getting six Sp-E clouds in the right spot and the correct distance apart is much lower.
The very first 6m contact between the USA and Saudi Arabia took place just a few weeks earlier when K1TOL in the state of Maine in the NE of the USA worked 7Z1SJ. The distance on that occasion was around 9933 kms which may have been five hop Sporadic-E.
