F2 Skip Zone on 28 MHz - 7th Dec 2023

As the WSPRnet website was down for most of today, I left the radio on the FT8 frequency of 28.074 MHz instead. As expected, there were a lot more signals on this mode.

One thing that stood out after a few hours was the skip-zone as shown in the map above. There was no sign of any real Sporadic-E and nearly all of the signals that I heard were coming off the F2 layer of the ionosphere.

The closest signals to the south-east were front central Italy around the 1700km mark. At this distance, the signals were probably coming in to my location about 25-degrees above the horizon. Anything closer than this resulted in a higher angle and propagation wasn't possible.

To the north-east, the closest stations were about 2300kms in the north of Sweden with no sign of anyone closer.

It's also interesting to note that all of Spain is missing, even the far south of the Iberian peninsula is too close for 28 MHz propagation today.

Impressive rollout of DAB+ network in France

I recently noticed that a new DAB+ radio network is being rolled out now in France. Broadcasting by radio is seen by many as a thing of the past and here we see a new radio network being installed in one of the largest countries in western Europe.

The traditional FM radios on Band 2 use 87.5 to 108 MHz with one station per frequency. The new DAB+ system uses Band 3 which goes from 174 to 240 MHz and has several stations grouped together on something called a multiplex. This allows for more stations to fit on a given band and more crucially, it allows space for new stations to enter the market.

By October of 2023, the French DAB+ covered the Paris-Lyon-Marseille corridor taking in all major urban areas along this route (shown below in purple).

By the end of March 2024, they hope that 60% of the population as shown above will be able to receive DAB+ radio stations.

As far as I know, no date has been set for any switch off of the 88-108 MHz FM broadcast band and I suspect both will co-exist for quite some time.

Link...
1) French DAB network... https://www.dabplus.fr/

Launch & Deployment schedule for EIRSAT-1

EIRSAT-1 is the first Irish satellite and I covered this in a previous guest post by Lez, EI4GEB.

The cubesat is going to be launched with 24 other satellites on a SpaceX Falcon 9 rocket from the Vandenberg Space Force Base in California at 18:19 UTC on Friday 1st December 2023.

Other satellites on board include KOREA's 425, Space BD’s ISL48, SITAEL’s uHETSat, D-Orbit’s ION SCV Daring Diego, York Space Systems’ Bane, and PlanetIQ’s GNOMES-4. This is also the 17th flight of the first stage booster supporting this mission, which previously launched Crew-1, Crew-2, SXM-8, CRS-23, IXPE, Transporter-4, Transporter-5, Globalstar FM15, ISI EROS C-3, and seven Starlink missions. Following stage separation, the first stage will land on Landing Zone 4 (LZ-4) at Vandenberg Space Force Base.

Sequence of events... Here is a timeline of what is expected to happen...

18:19 UTC - T=0 - Launch of Falcon 9 from California.

19:49 UTC - T+90 mins - EIRSAT-1 injected into a 520-km Sun-Synchronous Orbit somewhere over Norway.

20:34 UTC* - T+135 mins - Satellite’s antenna deployment somewhere over the South Pacific.

20:45 UTC* - T+146 mins - EIRSAT-1 will pass to the south of New Zealand & Australia. Is it in range? If it is, it's likely to be very low in the southern sky.

20:58 UTC* - T+159mins - EIRSAT-1 will pass over South Africa. 

21:18 UTC* - T+180 mins - EIRSAT-1 over Europe

*Approx

Frequencies...

EIRSAT-1 is not a communications satellite and does not relay signals. It has a number of experiments on board and it will transmit telemetry back to earth on the 70cms UHF band, at a frequency of 437.100 MHz. 

The downlink is GMSK modulated at a data rate of 9600 bps. Instructions for decoding the EIRSAT-1 beacon are available on the EIRSAT-1 instruction page.  

Doppler Shift... As EIRSAT-1 will be traveling at about 27,000kms per hour, there will be a significant amount of doppler shift on the signal at 437 MHz. The amount of doppler and how fast it changes will depend on whether the satellite is going directly overhead or is passing to the east or west and not too far above the horizon.

As a guide, you should tune to 437.110 MHz to first hear the satellite. As you track it, it will move down in frequency and it should be down around 437.090 MHz as it moves out of range.

See the website of VK3JED for some examples.

QSL Card from the European Space Agency... The first confirmed recording of EIRSAT-1 from each continent (Europe, Africa, Asia, North America, South America, and Oceania) within a week of launch will be rewarded with a QSL card from ESA. These “special postcards” confirm that radio contact was made, and will include acknowledgement of the help given by the winners to ESA and the EIRSAT-1 team in acquiring the first signals from EIRSAT-1. 

To enter this competition, please send in your recording, timestamp of passage over your ground station, and the location of your ground station to cubesats AT esa DOT int. Be sure to include “EIRSAT-1 competition” in the subject of the e-mail.

EIRSAT-1 Control Room in Dublin

EIRSAT-1 Experiments... EIRSAT-1 is Ireland’s first satellite, and was designed, built, and operated by students with the support of ESA Education’s Fly Your Satellite! programme. In addition to the radio transmitter, EIRSAT-1 houses three main experiment payloads, which were built from scratch by the student team:  

GMOD is a detector to study gamma ray bursts, which are the most luminous explosions in the universe and occur when a massive star dies or two stars collide.  

EMOD is an experiment to see how a thermal treatment protects the surface of a satellite when in space. 

WBC will test a new method of using Earth’s magnetic field to change a satellite’s orientation in space. 

Video... This non-technical 22-min video intended for the general public gives an overview of how EIRSAT-1 was conceived and built.

Links...

1) ESA- Calling all radio amateurs – be the first to hear satellite EIRSAT-1 from orbit

2) EIRSAT-1 technical data... https://github.com/ucd-eirsat-1/beacon

WSPR activty report for the 28 MHz band - Nov 2023

Every day for the last few months, I have left the radio listening on the WSPR frequency of 28.1246 MHz and I feed the spots up to WSPRnet. Most days, I don't even check what the radio heard, I just leave the radio on so that others can see how far their 10m WSPR transmitters are reaching.

I had a look today at what I heard for the last 5-weeks which is from the 26th of October to the 29th of November 2023. Considering that we're near the peak of the sunspot cycle, this post gives an idea of what what the band was like.

Totals & Distribution... In total, I heard about 1200 individual stations on 28 MHz during the 5-week period. This is a huge change from a few years ago when I would hear relatively few. It's not that conditions just got good but I think a lot of WSPR users came up to 28 MHz from the lower bands. 

There are a few false reports in the 1200 from strange callsigns out in the middle of nowhere but the vast majority of them are genuine.

The map above shows the distribution and it's obvious most of the WSPR activity is centred on North America and Europe. South America is surprising low and there is almost nothing from Africa outside of South Africa. There is however a good amount of activity from Australia.

DP0GVN... I heard the German Antarctic research station DP0GVN a total of 47 times during the 5-weeks. The best times seem to be in the afternoon but I heard it as early as 07:48 UTC and as late as 18:48 UTC.

Japan???... Where is everyone? I know there have been paths from Ireland to Japan on 28 MHz for people using FT8 but I heard nothing on WSPR. I checked some of the reports for some of the Australian stations and these seem to confirm that there seems to very little interest in WSPR in Japan.

North America... This is the distribution of stations in North America. For the USA, this pretty much mirrors the level of activity and population in the country. You can draw a line north from Houston, Texas and a lot of the radio amateurs are to the east of that.

From Ireland, it's pretty easy to hear the eastern half of the USA so it's nice to see all of those more difficult northerly paths to the west coast. This is especially true when I start seeing those VE6's and VE7's in the north-west.

I do have one report of hearing KL2OF in Alaska but I think it was bogus. I only heard it once, QRZ says the call has expired and the signal was only sent for one 2-minute period. 

I'm not even sure if a WSPR path is likely to Alaska from Europe considering the polar flutter on the signal at 28 MHz?

The UK on Backscatter... There are quite a number of stations in England using WSPR on 28 MHz and most of these stations shown above are about 400-700kms from my location. This is too short for single hop F2 layer and they are in my 'skip zone' according to usual propagation textbooks.

There might be some Sporadic-E in there but it's likely the vast majority are F2 layer backscatter. The 10m signal is being reflected off distant objects like mountains and ocean waves 1000's of kms away. It's certainly not aircraft scatter.

France - Où êtes-vous???... The map above shows the distribution of signals from western Europe. WSPR is popular in the Netherlands and Germany but where is all the WSPR activity from France???

It doesn't seem to be just a lack of transmitters either. There seems to be a equal shortage of people in France listening on the band and reporting.

Australia on 10m... It's always nice to see the 28 MHz WSPR signals from Australia coming through and I heard 29 VK stations in the 5-week period. For whatever reason, I didn't hear any VK7 stations from Tasmania.

As can be seen from the chart below, most of these stations are about 15,000 to 17,500 kms from my location.

Note the Signal to Noise reports (SNR). Most are these signals are buried in the noise and below what can be heard by the human ear. That's the magic of the WSPR mode.

WSPR seems to have a niche following in Australia and those guys are doing some interesting work investigating propagation paths on the 50 MHz and 144 MHz VHF bands.

Polar Stern... Nearly all of the WSPR signals are from stationary stations but a few are on the move. The map above shows my reception reports of the German polar research ship Polar Stern which uses the call DP0POL. It went through the English Channel a few weeks ago and made it's way down to South Africa.

Some days, propagation is good and I get a string of reception reports resulting in a blurred line. Some days, I heard it only a few times if t all.

Path of pico-balloon AF6IM

Pico-Balloon AF6IM... The very small balloon AF6IM was launched from California a number of weeks ago and it has gone around the world at least once. See my previous post.

The map above shows where I heard it over the last few weeks.

In summary... As a beacon mode, WSPR won't be of interest to everyone but it's nice to see a good level of interest in the mode especially on the 28 MHz band.

Just for reference, I was using a simple CB type half-wave antenna for this test so nothing special on my side.

Link...
1) The best website to check WSPR reports is http://wspr.rocks/

F2 opening on the 50 MHz band across the North Atlantic - 27th Nov 2023

As we approach the peak of the solar cycle, things are beginning to improve on the 50 MHz (6m) band with some F2 layer propagation appearing.

In general, north - south openings are the first to occur on the 6m band as the conditions improve in the F2 layer of the ionosphere. You'll see reports of openings from the Europe to South Africa and from North America to South America. Nice openings but nothing to get too excited about.

The openings to watch out for are the east-west ones from more northerly latitudes. These paths are much more difficult so it was interesting to see an opening on the 27th of November 2023 from the north-west of Europe to North America.

The image above shows the FT8 paths for EI7BMB near Dublin and it's an example of what the opening was like. It's likely that the path from Ireland to Newfoundland was the only single F2 hop. All of the other longer paths required at least two hops.

The most westerly station was W5LDA in Oklohoma.

The image above shows the 6m paths for K1TOL in the state of Maine. The most interesting paths here are the most northerly ones with an opening to the north of Denmark and the south of Sweden.

The solar flux on the day was 187. This isn't going to be a one-off and there should be plenty more east-west openings on the 50 MHz band across the North Atlantic over the next few weeks. Check around 13:00 to 16:00 UTC.

It'll be interesting to see over the next few weeks if there are any openings from the west coast of the USA to the north of Europe.

Evolution of modern Direct RF radio receivers

 

I recently came across a 15-minute video presentation from Analog Devices about cutting edge radio receivers and I have embedded it at the end of the post. I think anyone with an interest in RF technology will find it of interest.

The image above shows the evolution of receivers.

A) We have the Superhet receiver which was the stable design for many decades. In amateur radio transceivers, there were usually two IF (intermediate frequency) stages... one often around 8-9 MHz and the second one at 455 kHz. Anyone who has a radio from say the 1980's or 1990's will probably have this design. Functional but complex and expensive.

B) We have the more modern Zero IF or No IF design. A digital local oscillator generates two local oscillator signals with one 90 degrees out of phase relative to the other one. These are fed to two mixers which then generates an I and Q signal which are at baseband. These signals are then converted into a digital signal by two ADC's (Analogue to Digital Convertors). There is no IF stage. Many modern receivers use this design.

C) The most recent development is to directly sample the RF signal with no mixers at all. Essentially the signal comes into a RF filter, then a low noise amplifier and then it goes to the ADC where it get's converted into a digital stream.

This images above is a screenshot from the video presentation and it shows the modern generation of Direct RF receivers going up to 18 GHz! I still find it amazing that an IC can sample RF signals in the tens of MHz range let along going all the way to 18 GHz.

Needless to say, all of this cutting else stuff is expensive and is aimed at commercial and military users but it shows the direction of travel. In time, the technology will trickle down and will appear in lower cost products.

Video... The main part of the video is from 3:10 to 7:30 if you want to skip ahead. The second half of the video after 7:30 is about the most recent Analog Devices product.

28 MHz Summits on the Air Challenge for 2024

One of the popular amateur radio award programmes is Summits on the Air (SOTA) and it's relatively easy for people to activate a peak as opposed to going to some exotic DX location.

Andy, MM0FMF has announced a new SOTA Challenge for the 28 MHz (10m) band for all of 2024. It's nice to see a specific challenge for the 10m band and hopefully, it will generate some more activity on this band now that we're near the peak of the solar cycle.

2024 10-metre SOTA Challenge 

Andy MM0FMF writes... "Back in 2013/2014 we were coming to the top of Cycle 24 and we decided to have a challenge. The aim was to encourage activity on the 12m band. I chose 12m for a few reasons, it has almost identical propagation to 10, there’s no contests, it was a very underused band in SOTA, I could fit a 12m 1/4GP on my fibreglass pole. The last was important, I didn’t need to spend any extra money :wink: Huge fun was had by people who took part, much DX was worked. My most memorable QSOs were random chases by VK stations to the UK at lunchtime rather than greyline.

So now Cycle 25 it starting to show it means business and we enjoyed just how much fun can be had on the higher bands in the recent NA<>EU S2S activity day when the Sun produces SFI figures around 150 and we get people organised to be on the air at the same time.

It’s the right time to run another challenge. We’ve done 12m and we didn’t pick it again because we try to be inclusive on SOTA and I didn’t check 12m allocations worldwide last time. Not every licence class gets access to 12m, in some countries only the top licence types get access. But on 10m the situation is very different with most licence types giving some or complete access, more people can take part than on 12m.

The aim of the challenge is to get everyone using 10m a lot. Since 2013 we have added 95 new associations with many in South America, Asia and the Caribbean. So now there should always be DX for someone workable :o) (Don’t forget, EU is DX for some!)

Andy, MM0FMF activating a SOTA summit

Scoring will be done automatically by the database software. You just need to enter your activations and chases as normal, the software will note 10m QSOs and score them according to the rules below. Normal SOTA rules apply so if you do a multi-band activation, just enter it as normal and your normal SOTA results get updated and qualifying 10m QSOs get scored completely separately.

There will be a special 10m Challenge results page. But note, lots of you said you don’t want SOTA contests and we listened. There will not be an overall winner or association winners. The challenge results pages will be sorted alphabetically by callsign and you will be able to see how well you are doing . If you want you can compare your results with others to see if your equipment is as good or if you get a better score per activation etc. A certificate will be available showing your name, call, association and score.

The challenge runs from 0000Z January 1st 2024 to 2359Z December 31st 2024

Scoring for chasers:
For every unique summit you chase on 10m you get a multiplier.
For every unique activator you chase you get 1 chaser challenge point.
Your final score is chaser challenge points * multipliers.

Scoring for activators:
For every unique summit you activate on 10m you get a multiplier.
For every unique chaser you work you get 1 activator challenge point.
Your final score is activator challenge points * multipliers."

For more information about the Summits on the Air award programme, go to https://www.sota.org.uk/

Amateur Radio accounts for just 17% of ICOM's business

ICOM is well known as one of the key manufacturers of high quality transceivers for the amateur radio market. In May of 2023, they released a document titled 'Medium Term Business Plan 2026' which outlined the company's plans for the financial year March 2024 to March 2026.

As the graphic above shows, ICOM are involved in several radio and communication sectors but I think most people would be surprised to learn that amateur radio only accounts for 17% of ICOM's business.

In terms of future plans and growth for the future, they had this for the section about amateur radio...

It's a bit like saying something without actually saying anything. It's well known that the amateur radio community is getting older and it's not a growth market. As long as ICOM can make money selling equipment to radio amateurs, they'll stay in the market.

The original document is pretty bland and if you want to read it, you can find it HERE

Inter UK contacts on 14 MHz possible as skip distance shortens to 500kms - Nov 2023

Most weeks, I skip through the news bulletin from the RSGB and I found this item of interest.

RSGB News... "Propquest shows that the F2-layer critical frequency is still maxing out at more than 12MHz around noon. The F2-layer critical frequency is the highest at which radio waves are returned back to Earth when sent directly up into the ionosphere.

This gives us a maximum usable frequency, or MUF, over a 3,000km path of more than 40MHz. Interestingly, it also gives us an MUF over a 500km path of more than 14.7MHz. So, look out for long-distance inter-G signals around noon, or thereabouts, on the 20m band. 

The 30m band remains a pretty solid inter-G band from late morning to mid-afternoon."

On the face of it, it should come as no great surprise. If a signal can go straight up (90 deg) to the F2 layer of the ionosphere and come back down at 12-MHz then a skip distance of about 500kms on 14-Mhz sounds about right.

The diagram above shows the path of the signals. The 14-MHz signal will eventually reach a low enough angle... i.e. the critical angle so that it can return to point B.

Back in February of 2017, I was working some Spanish special event stations during what was then the minimum of the sunspot cycle. The shortest path back then on 14 MHz then was around 1500kms.

Now in November 2023, we're near the peak of the sunspot cycle with a higher solar flux and the skip distance on 14 MHz has reduced to about 500kms at midday. This 'short skip' distance on 14 MHz should apply to other stations as well in say North America or Europe if they're located below say 60 deg latitude.

From my perspective here on the south coast of Ireland, the whole of the UK is generally within my skip distance on the higher HF bands. On bands like 14-MHz, it's normal to hear stations from say Germany but not the UK.

There are times during the summer Sporadic-E season when short paths are possible but usually not in November.

28 MHz... The shorter skip distances also applies to the higher bands. The minimum distance now on the 28 MHz (10m) band should be around the 1500km mark, maybe a little less.

4,200km opening at 88 MHz between Africa and Brazil - Nov 2023

George, PU7MAN  on his FM DX Brasil Twitter account reports a 4,200km opening recently on the FM Band 2 between Africa and Brazil.

The station in question was the 8-Kilowatt transmitter of Radio Cote D'Ivoire near the capital Abidijan on 88.0 MHz. According to the FM DX Brasil account, the signal was heard at a remote receiving station at Nova Russas in the state of Ceará in the NE of Brazil.

The equipment used for the reception was an Airspy Mini SDR receiver with a 3-element Yagi for the FM band.

The signal was heard at 23:30 UTC. The Twitter post was on the 15th of November 2023 so it was perhaps at the same time as the reception?

Propagation Mode???... Nova Russas is located about 200kms or so from the Atlantic Ocean and isn't on the coast. I suspect it wasn't a form of tropo ducting as this is an area of low pressure systems at the equator and the distance was over 4000kms.

The propagation mode wasn't TEP (Trans-Equatorial Propagation) as the path ran almost parallel to the Geomagnetic Equator (E-W) and not across it (N-S).

There are some remarkable reception reports across South America on the FM band and some people attribute these to Spread-F. Was it that?

There is an audio clip embedded in this Twitter post...

RTI - 88.0 - Abidjan /COTE D'IVOIRE AFRICA
Airspy Mini
Yagi 3 elems / Remote Location / Nova Russas/Ce/ Brazil
23:30 UTC pic.twitter.com/flPUtKLHmc

— FM DX Brasil (@FMDXBrasil) November 15, 2023

At his home location in Sorbal, PU7MAN recorded this audio clip on the 14th of November 2023 after 23:00 UTC using a Kenwood BT3012u radio withe a Triax FM8s antenna...

Link...

1) For more examples of long range reception reports on the FM band, see my 88-108 MHz page.

A new PC and a move to the LOG4OM logging programme - Nov 2023

After putting it off for several years, I finally bought a new PC! It wasn't so much the cost of changing but I just kept putting it off with the thought of all the hassle of setting up a new PC and the transferring all of the files and programmes. However, it got to a stage where the old PC was getting so slow that I had to change it and now that I have, it's super fast compared to the old one.

One of the long term things on my 'to do' list was to update my logging programme. I said that I'd do it when I got a new PC instead of putting yet more software on the old PC. It didn't help that I was off the radio for several years and I didn't have any interest in doing it but now that I have a new PC, that has changed.

I used to use the VQLog logging programme for all of my contacts before but I hadn't used it in many years and it was installed on an even earlier PC. 

VQLog... VQLog is quite an old logging programme as can be seen from the image above but it looks as if it is still being updated. It's obvious most people have moved onto other programmes but I thought it might be easier to relearn how to use VQLog than to start with a completely new logging programme.

I went to the DXMaps website and I downloaded the most up to date version... VQLog 3.1 - 717

During the stall, it was initially stopped by my anti-virus software. After allowing access, I eventually got this message...

When I checked the FAQ section on the website, I read the following...

When installing the program I get the following error "C:\WINDOWS\ST6UNST.EXE C:\WINDOWS\  the file could not be installed"
This is a rare error that seems to be related to a missing or corrupted cabinet.dll file. (That should normally be located in C:\Windows\System32).  You have to restore the original cabinet.dll file. You can also download it

If I got this message on my old PC then this might seem valid but my PC is only 3-weeks old! If I'm getting this message then anyone else with a new PC trying to install it is probably getting it as well.

My conclusion is that the problem lies with VQlog and not on my side.

One of the major factors in any logging programme is the amount of time it takes you to input data and keep it up to date. The cost of the programme is really a secondary factor. Getting error messages trying to install a programme on a new PC doesn't inspire confidence and I decided it was time to move on to another logging programme.

LOG4OM... There seems to be plenty of logging programmes out there but which one to choose?

My criteria were...

1) Must be popular so that it has a large user base

2) Must be current

I had heard of the LOG4OM logging programme before but it didn't really stand out compared to the rest. Sometimes it's the small little things that push you in a certain direction. I had watched a video presentation by South Dublin Radio Club about the LOG4OM programme and the participants seemed happy with it.

I checked the LOG4OM forum and there were plenty of current messages which meant a lot of people are currently using it. So I downloaded it and installed it without any error messages or the like. It was a very easy process unlike VQLog.

Like any new programme, there is a steep learning curve but I'm now a week into using it and getting used to it.

I should also note that LOG4OM is a free programme which is a plus but as I've mentioned already, it wouldn't be the primary factor for me.

LOTW... Now that I have restarted with a new logging programme, I decided to check my Logbook of the World (LOTW) account on the ARRL website.

My last upload was way back in January of 2009! I have 22,448 QSO's up there with 4,053 QSL records.

From what I can see, it's possible to download all of the confirmed QSO's as an ADIF file from the LOTW site but not all of the QSO's that you uploaded originally. I did this and imported the 4,053 records into my LOG4OM programme.

In conclusion... The plan now is to start inputting QSOs manually from my paper logs from Jan 2009 onwards to the present day into LOG4OM... about 2,500 contacts. When I finish, I plan to upload these and I will then  have all of my 25,000 or so contacts up on the LOTW website.

GB3MCB 40 MHz & 60 MHz beacons off air due to storm damage

Peter, G8BCG reports that the GB3MCB beacons on 40.050MHz & 60.300MHz are off air due to recent storm damage.

This beacon in Cornwall in the far south-west of England was the only 8m & 5m beacon in the UK. Both were running 5-watts into an omnidirectional "turnstile" antenna.

As we are currently near the peak of the sunspot cycle, it will hopefully be repaired soon.

Video: Talk on End Fed Antennas for the HF bands ...by MM0OPX

As part of the RSGB Tonight at 8 video series, Colin, MM0OPX gave an entry-level talk on End Fed Half Wave antennas for the HF bands.

This is more of an overview of this type of antenna rather than a step by step guide on how to build one. 

It might be of interest to those who like to build their own antennas or someone who likes operating portable.

See the video below...

Skewed path on the 24 MHz band between Europe and the Pacific - Nov 2023

I found this item in the most recent GB2RB news bulletin from the RSGB of interest... "Phil, GU0SUP reports working Jan, E51JAN on the North Cook Islands on 12m FT8 Fox and Hound mode at around 1630UTC. He said that, as it was almost dark, he didn't expect to hear anything, but had a good copy on him at 190 degrees, so gave him a call. He came straight back.

Phil said that this was a big surprise, and he is not sure how it worked. It was quite a skewed path, with pretty much no copy on the real headings, short or long path."

The map above roughly shows the various paths for this 24 MHz (12m) band contact. From GU0SUP's location on the island of Guernsey, the short path goes up over Greenland. The long path would go in the opposite direction (148 deg) and down over Africa.

The reported path of 190 degrees takes the signal down into the Atlantic region between South America and Africa.

Commentary... The QRZ page for GU0SUP says that he is using a TGM Communications MQ26 mini-beam which would have a very broad beamwidth. We can't know for certain if the actual path was 190 deg or not. 

All we can take from the report is that it wasn't short path or long path but was skewed in roughly a south-westerly direction.

The image above is one I made before for an opening on the 50 MHz band between Europe and the South Pacific with a skewed path. Post HERE

This most recent report for the 24 MHz may well be the same? Did the signals get trapped in the Trans-Equatorial Propagation (TEP) region and allow the skewed path westwards from Europe to the Pacific?

Skewed paths should be even more common and pronounced at a lower frequency like 24 MHz as compared to 50 MHz.

I suspect that the TEP region has a huge impact on signals that most of us don't appreciate. On the HF bands, so many people are using omni-directional antennas or beams with a very low beamwidth that skewed paths are not obvious unless they are at almost right angles to the short and long paths.

Food for thought... How many people on the HF bands are looking for DX-peditions or DX stations on the textbook short or long paths when they should be thinking outside the box and looking for skewed paths?

Backscatter on 28 MHz - 2nd Nov 2023

For well over 12-months, I have had my radio tuned to the WSPR frequency of 28.1246 MHz on the 10m band and I feed the decoded signals up to the WSPRnet website.

While I can see the WSPR signals clearly on the waterfall display, I can also see the very slow morse QRSS signals as well just a few hundred Hz below.

The image above shows the QRSS signals I could see on the 2nd of November 2023 and the locations of the stations are shown in the map at the start of the post.

The screenshot above shows a good capture of AE0V in the USA at about a distance of 6000kms. Ned, AE0V reports using a solar powered transmitter with no battery storage running 100mW into a 1/4 lamba stainless whip about 8m above the ground.

The signals from the USA and Canada are easily explained as they are via F2 layer propagation. The signals I find unusual are the ones from the England which are in the region of 500 to 650kms.

The trace from the 0.2-watt signals of G0PKT and G0MBA are there nearly all the time when the band is open. It's not F2 propagation in the usual sense as it's too close and it's not Sporadic-E.

I believe that it's backscatter just like what the military use for their over the horizon radar systems (OTHR). 

In this case, the 28 MHz band is open with F2 layer propagation and the signals from G0PKT & G0MBA are being reflected back towards my location from some distant point.

As an example of how consistent these signals are, I have decoded the WSPR signal of G0PKT about 1,000 times in the last 3-weeks. And that's a signal that's supposed to be in my 'skip zone' where it's supposed to be hard to reach.

There's nothing new about this, it's just that in this modern age of weak signal modes and waterfall displays, we can now see these very weak signals more clearly. 

If you're using FT8 on the higher HF bands and you see lots of reports from stations that about 200-600kms away then F2 backscatter is probably the reason.

Tracking the AF6IM Pico-Balloon on 28 MHz from the USA to China - Oct 2023

For the last 12-months or so, I have been being monitoring the WSPR beacon frequency of 28.1246 MHz nearly every day and uploading the reception reports to the WSPRNet site.

I noticed recently an unusual signal out in the Mid-Atlantic.. AF6IM. I thought at first it was a bogus WSPR report but then I noticed that I had heard the signal several times and it was moving!

After some checking, I discovered that the signal was actually from a Pico-Balloon with a 13-milliwatt WSPR transmitter underneath it. It was launched by Mark, AF6IM in California at the end of Sept 2023 and it has been slowly drifting eastwards since. At the time of writing on the 26th of October, it is over China.

The map above shows my reception reports of the 13mW beacon. It only operates for a few hours every day as it is solar powered and has no battery. That's why the signal is shown as small batches of signal locations in a row.

The pictured is further complicated by the fact that Mark actually had two 28 MHz Pico-Balloons in the air over the last few weeks.

The design of the WSPR transmitter is shown above and you can find more information about it HERE

The antenna for this 28-MHz transmitter is a very thin wire which is 2.54 metres long which is a quarter wave on 10m.

This photo by AF6IM shows the pico-balloon at launch. As the balloon gains altitude and the pressure reduces, the size of the balloon will get larger.

The solar cells are not shown.

Even though the original balloon looks very small, it's still able to keep a very small payload aloft at a high altitude. The chart above shows the launch of the balloon and floating along at an altitude of about 12,500m or 40,000ft. This is well into the Jet Stream and this is what is now carrying it  around the world.

The temperatures at this altitude are well below zero as can be seen in this image above. One obvious advantage in not carrying a battery other than additional weight is that there are no problems with a battery trying to survive at these low temperatures.

In conclusion... There have been plenty of other pico-balloons operating on lower frequencies in the past like on 14 MHz but I really don't have much interest in those bands. This is the first time I recall seeing one operating on 28 MHz.

What I find fascinating is that I have heard the little 13-milliwatt 28 MHz transmitter over 450 times over the last few weeks while it was hanging below a little balloon up in the Jet-Stream.

If you want to track it, you can follow it HERE

6,100km TEP opening on the 144 MHz band from Uruguay to the Caribbean - 21st Oct 2023

As we head towards the end of October 2023, there have been reports of some TEP (Trans-Equatorial Propagation) openings in South America on the 144 MHz band.

Carlos, CX5CBA in Montevideo, Uruguay writes... "As of the 21st of October 2023, there have been TEP openings every night for two weeks between South America and the Caribbean.

I have been able to make several contacts on 144 MHz on SSB and Q65 with a 4.7m long Yagi antenna and 50W. The stations worked are:

SSB: HI8D, HI8AN, HI8GSP, NP4BM
Q65: HI8D, HI3I, HI8T, NP4BM, PJ4GR."

The map above shows the path of one of these contacts between CX5CBA and HI8D. Note that the Geomagnetic Equator is almost equidistant from both stations and the path is at right angles to the Geomagnetic Equator as well. This is pretty much the ideal path for a TEP opening at 144 MHz.

The other stations NP4BM (Puerto Rico) and PJ4GR (Bonaire) are also located in the western part of the Caribbean. This follows the typical pattern for TEP openings in South America at 144 MHz... i.e. stations in Uruguay and Argentina work the Dominican Republic, Puerto Rico and Bonaire whereas stations in the south of Brazil usually work the eastern part of the Caribbean - Martinique, Guadeloupe, etc.

This is a log extract from CX5CBA...

It shows several contacts made on SSB which means the signals must have been reasonably strong.

You'll notice the one CW contact on the 50 MHz band to V31XX in Belize. With lower frequencies like 50 MHz, signals that are not as close to right angles can propagate.

This screenshot from Carlos shows that some on the contacts were made with the Q65 mode.

This screenshot shows the callsigns, signals and time. Note the time... about midnight UTC which is about 9pm local time in Uruguay.

Comment... Thanks for Carlos for the report and images. While these TEP openings at 144 MHz are pretty common, we should still remember that we are looking at contacts that are over 6,000 kms in length.

It's also a reminder that the TEP season is in full swing in South America and it's time to check out 50 MHz, 88-108 MHz and 144 MHz.

It would also be very interesting to see some stations doing TEP experiments on the 432 MHz (70cms) band.

Link... For more examples of long distance 144 MHz contacts, see my 144 MHz page.