2024 10m QRSS Challenge: - VA1VM 10th Jan

As part of a challenge for 2024, I've decided to see how many QRSS signals I could capture on the 28 MHz band during the year.

QRSS are very slow morse code transmissions where the dots and dashes are several seconds long and the signals are decoded by looking at a waterfall display on a screen rather than listening to the signal.

The QRSS signals are usually just below the WSPR signals on the amateur radio bands. This means it's possible to have your PC decoding WSPR signals up around 1500 Hz while you look at the QRSS signals about 500 Hz or so lower in the audio spectrum at the same time.

2024 #2 - VA1VM... The first signal I captured in 2024 was from Vernon, VE1VDM in Nova Scotia, Canada back on the 8th of January. This is outlined in this previous post.

Conditions on the 28 MHz band were better on the 10th of January and the 'VDM' QRSS signal was in again but stronger as can be seen above. For this beacon, Vernon was using a QrpLabs U3S with low pass-filter into a QrpLabs power amplifier delivering 1-watt on 10m. The antenna was ground mounted Hustler 6BTV vertical.

In the last 24-hours, Vernon has put a second QRSS transmitter on the air with the callsign VA1VM. You can see this as a weaker signal in the image above.

The VA1VM signal is from a 150 milliwatt transmitter into a  Hustler 10m 1/4 wave resonator mounted on a 1.37-metre long Hustler mast extender. It really is amazing that a 0.15 watt signal can make it across the Atlantic.

Both beacons are located in the town of Truro in Nova Scotia and are just a few kms apart. The antenna on my side was a simple CB type half-wave vertical.

The map above shows the location of the transmitter and receiver. The distance is about 4000kms which is ideal for 1-hop of F2 layer propagation.

Even though it's the same person, it's a second QRSS signal. That brings the QRSS tally so far for 2024 up to 2-callsigns & 1 DXCC.

08 Jan 2024: VE1VDM
10 Jan 2024: VA1VM

Tracking a high altitude balloon over Ireland on the 70cms band - 9th Jan 2024

 

Thanks to Robbie, EI2IP putting a post up on Facebook, I noticed that a high altitude balloon was crossing over Ireland due to the easterly winds over the country and it was transmitting on the 432-440 MHz 70cms band.

I remembered that I had managed to decode RTTY signals from a balloon over the UK a few years ago and I found it fascinating. It was always something on my 'to do list' to try again but I forgot all about it. When I checked today, that reception report was back in in July of 2018!

So there was no time like the present, I followed the links and started reading about it. 

Part 1 of 2... The high altitude with the amateur radio payload was named Flybag-2 and had been launched from Maastricht in the Netherlands. It was transmitting on two frequencies on the 70cms band with data on it's location, height and internal temperature.

The payload was transmitting using the Horus Binary (v1/v2) modulation format which is a digital signal that is way superior to the old RTTY mode.

I downloaded the software to decode the Horus Binary signals, starting to mess about with the various settings, tuned the radio to 437.600 MHz USB and listened....silence. 

The balloon had just cross over the east coast of Ireland and was heading west. I was using a homemade vertical colinear in the attic of my house which wasn't the best for listening for weak signals from a tiny transmitter 120kms away.

I also had the WSJT-X software running as well and I could make out weak traces in the waterfall. I tuned the radio down about 500 Hz to 437.5995 MHz. Eventually I could hear the signal weakly but still no decodes. Time to read the instructions.

The instructions said the audio level needed to be near -5dB. I had the volume well down and the software said it was 'good'? I tried turning the volume of the radio way up and success!

The stats show that I managed to get 20 decodes in total which is 20 more than I thought I'd get. The attic antenna is really blocked a lot in that direction so I was delighted to get anything.

Part 2 of 2... A few hours after Flybag-2, another balloon named Flybag-4FSK crossed to the south of Ireland. I had a lot more success with this one getting 71 decodes in total with my attic antenna.

The first decode was when the balloon was about 300kms away over the Bristol Channel and just below the horizon. My view to the east is pretty good and this resulted in a lot of decodes.

It was interesting to note that the signal was reasonably consistent up to about 00:24 UTC and then it dropped suddenly and the last decode was at 00:40.

This is the location of the balloon relative to my location. The balloon is slowly moving to the left (left).

This is the horizon from my location. The balloon from my point of view would have been moving slowly from roughly east to the south of me and then to the south west.

When the balloon was to the south-east, I was getting a lot of decodes as my horizon is close to 0-degrees in that direction. Once it got to 00:24 UTC, the local hill had an elevation of 1-degree. Beyond that, the signal dropped as the elevation of the hill got higher. 

After 00:40, the local hill had an elevation of about 3.5-degrees and it was now blocking the signal.

I knew my take-off in that direction was poor but it was interesting to see conformation of it.

High altitude balloon... There are generally two types of balloons. The one I heard back in 2018 was like a weather balloon, it went up to an altitude of about 20kms and then the balloon burst.

This time, the balloon reached a height of about 4kms where it levelled off. Unless the hydrogen/helium gas escapes or it hits rough weather, it should stay up for quite some time.

STEM... It also strikes me that this would make a great STEM project. Schools and colleges can't afford microsats but a low budget balloon could teach a lot about tracking, propagation, layers in the atmosphere, weather, etc. 

For more information, go to https://amateur.sondehub.org/

2024 10m QRSS Challenge: - VE1VDM 8th Jan

As part of a challenge for 2024, I've decided to see how many QRSS signals I could capture on the 28 MHz band during the year.

QRSS are very slow morse code transmissions where the dots and dashes are several seconds long and the signals are decoded by looking at a waterfall display on a screen rather than listening to the signal.

The QRSS signals are usually just below the WSPR signals on the amateur radio bands. This means it's possible to have your PC decoding WSPR signals up around 1500 Hz while you look at the QRSS signals about 500 Hz or so lower in the audio spectrum at the same time.

2024 #1 - VE1VDM... The first signal I captured in 2024 was from Vernon, VE1VDM in Nova Scotia, Canada.

Vernon was using a QrpLabs U3S with low pass-filter into a QrpLabs power amplifier delivering 1-watt on 10m. The antenna was ground mounted Hustler 6BTV vertical.

The antenna on my side was a simple CB type half-wave vertical.

The map above shows the location of the transmitter and receiver. The distance is about 4000kms which is ideal for 1-hop of F2 layer propagation.

So that's the QRSS tally so far for 2024... 1-callsign & 1 DXCC.

Reception of the 50 MHz GB3MBA beacon during the Quadrantids meteor shower - 4th Jan 2024

Back in December, I carried out an experiment to find and record the peak of the Geminids meteor shower by listening to the GB3MBA 50 MHz beacon which is 500kms from my location. See post HERE

On the afternoon of 4th of January 2024, there was the peak of the Quadrantids meteor shower which tends to be very narrow but intense. This time, I just took some screenshots of the meteor reflections.

Introduction... Back in 2022, a new radio beacon called GB3MBA was put on air on the 50 MHz band and its primary purpose was carrying out meteor scatter experiments. Located near the town of Mansfield in the centre of England, the beacon runs 75-watts into a small Moxon antenna which beams straight up.

Unlike most amateur radio beacons, this one is basically a carrier that is on nearly all of the time which is exactly what is needed for meteor scatter experiments. The main coverage area is the UK itself but as I'm 502 kms from the beacon, I'm close enough for it to be of use.

For the Quadrantids meteor shower, I was using a Yaesu FT817 on USB as a receiver and the antenna was a 2-element Yagi in the attic of my house. The antenna was beaming about 120 degrees which is about 45 degrees off the beam heading for the beacon (The choice of beam heading is determined by the space in the attic and I wasn't trying to beam away from the beacon).

Quadrantids screen shots...

The image above shows the composite collection of seven different screenshots. As can be seen, there was plenty of evidence of pings and bursts from the GB3MBA beacon.

The images on the blog are quite small and a link to a larger version of the image is on Facebook HERE.

I'll use the more detailed example above to explain what you are looking at. The time is moving from right to left and you will notice the 30-second timestamps. As my receiver isn't GPS locked, I'm probably around 5 Hz off frequency which is ok. 

If I was hearing the beacon directly, it would show up as a solid yellow line going across the centre of the screen. Instead, you are looking at the signal reflecting / refracting off the trail of electrons left behind by the meteor as it burnt up. As these electrons are in motion in different layers of the upper atmosphere, there is some doppler shift on the signal.

In the example above, the 50 MHz signal lasted for about 90-seconds.

The signal on the far right of the image above is one of my favourites. This is called an 'epsilon' echo as it twirls around. What causes such a complex pattern as opposed to the other 'smudges'?

Link...
1) GB3MBA website

40 MHz report from Bill Smith, W1-7897 for Dec 2023

Thanks to short wave listener Bill Smith, W1-7897 for sending on his reception report for December 2023.

Bill who is located near Douglas in Massachusetts in the United States is using a Yaesu FT-847 as a receiver on the 40 MHz (8m) band with a 5-element beam for the 50 MHz band.

Bill reports slim pickings on the 40 MHz band of late but did manage to log Jack, LX5JX in Luxembourg on the 27th of December 2023 calling CQ from 13:34 to 13:39 UTC. Bill reports that the FT8 signal strength was from -9dB to -17dB on 40.680 MHz.

As can be seen from the map above, the path was about 5,800 kms and was most likely two F2 layer hops.

Thanks for the report Bill!

For more information on the 40 MHz band, go to https://ei7gl.blogspot.com/p/40-mhz.html

Blog stats for 2023...

Before we get too far into 2024, I had a quick look back at the traffic to the blog in 2023. As can be seen from the chart above, the average number of pageviews in 2023 was about 20,000 per month. 

I should note that pageviews doesn't mean the actual number of people. If you were to visit the site every day then you'd generate 365 pageviews for the year. I'd guess very few people visit every day and 20,000 is still a significant amount of traffic for a blog about amateur radio and radio technology in general.

The volume of traffic during the year fluctuated quite a lot during the year and that is reflected in the number of times I posted...

2023 (110)
December (14)
November (12)
October (5)
September (1)
June (1)
May (3)
April (3)
March (15)
February (23)
January (33)

I put up posts nearly every day back in January and February, once every two days in March and then I hardly posted anything for months. This had an obvious impact on the level of traffic to the blog.

When I post every few days, the blog gets about 600-800 pageviews per day. If I don't post anything then the daily traffic drops to about 200-300 pageviews per day.

The thing is that the blog is just a hobby for me. It's not a job and if the site gets a lot of hits then great but it's not my reason for posting. I generally blog about things I find of interest regardless of how popular it might be to others.

Each post could take about two hours to prepare and sometimes longer. If I don't find the subject of interest then I don't bother.

How it works... The process for generating a blog post works like this...

1. I see something that is of interest to me. I can see that the news item isn't reaching a large audience / should get more publicity / wasn't fully explained.
2. I then generate a blog post about the news item of interest and include maps, diagrams and an explanation if necessary.
3. The blog post can take around 2 hours to generate, sometimes longer.
4. Links to the blog post then go out on social media so more people can notice it.

Missing posts... As for the lack of posts from April to October...

I get distracted! 😂 I'm off doing other things with my time.

Staying in the loop of the usual news sources takes time and it can take a while to even get back into the routine again.

Traffic Sources... I guess it would be natural to assume that most of the traffic to the site comes from Ireland but that's not the case. These are the largest countries by traffic by country during the year...

United States 63.1K

United Kingdom 13.9K

Germany 13K

Netherlands 10.6K

Ireland 8.37K

Italy 6.36K

France 4.75K

Canada 2.37K

The chart above shows the number of posts per year on the blog. 2022 and 2023 were pretty modest with about 110 posts each for the year. Still though, the traffic for 2023 seems pretty healthy compared to previous years despite the lower number of posts.

Social Media... As for the social media channels...

The EI7GL Facebook page now has 551 followers.

The Twitter / X account has 1429 followers.

The Instagram account has 310 followers.

In conclusion... It would be easy to make a New Year's resolution and say I'll post more this year but I know it will be harder once the evenings get longer. I have a few plans for the blog which I'll cover in a separate post which might change things a bit. I know whatever I do, I'll have to find it interesting to keep my focus.

ARRL raise membership fees as numbers drop

The American Radio Relay League (ARRL) is the national society for radio amateurs in the USA and is one of the largest if not the largest such organisation in the world. They also produce the QST magazine which is one of the largest amateur radio magazines in the world.

Back in July of 2023, they announced that they would be increasing their membership fees by between 20% to 71% at the start of 2024. In this post, I'll look at some of the changes.

Membership - US Members...

• US members of the ARRL paid $49 per annum up to and including 2023. For that fee, they were able to receive the QST magazine by standard post. As of the 1st of January 2024, that membership fee now increases by 20% to $59 and for this, they will have access to only the online digital version of QST.
• If US members wish to keep receiving QST by standard mail then they will have to pay $84, a 71% increase on their old subscription of $49.
• US members who were getting QST by first class mail will see their subscription increase by 37.5% from $96 to $132.
• Three year membership fees follow much the same pattern... 3-year membership with QST mailed out goes from $140 to $174 for membership and digital QST only, a jump of 24%. To keep getting QST by mail for 3-years, members will have to pay $249 instead of $140, a 71% jump.

Membership - International Members... As non-US members, it's probably fair to say that most international members have joined to get access to the QST magazine.

• International members who currently get the digital version of QST will see their fees go up by 20% from $49 to $59. The 3-year option goes up by 24% from $140 to $174.
• International members who currently get QST by standard mail will see their fees increase by 25% from $76 to $95. The 3-year option goes up by 30% from $217 to $282.

Big changes as numbers fall... The last increase in membership fees was 8-years ago in 2016 so some may feel that an increase is inevitable. I suspect the size of the jump this time though will be too much for some.

In 2022, the ARRL saw an unexpected 4% drop in membership numbers as can be seen above. This I presume was due to the cost of living crisis and inflation and for some, ARRL membership was something they could do without. This suggests that ARRL membership is sensitive to price and all of this happened well before the price increase at the start of 2024.

The ARRL membership numbers since 2001 are shown above. You can see the strong growth up until 2015 and then the drop once the membership fee was increased from $39 to $49.

In 2016, the membership fees were increased when the numbers were at a peak. That is in marked contrast to now when membership seems to be in decline. They have yet to announce the 2023 membership numbers and there may well be a mini-surge as people avail of the lower prices before the prices go up. 

However, the latest stats from the FCC shows that the number of radio amateurs in the USA has dropped about 2% in 2022 and is back down to roughly what they were in 2018. It seems that a large recovery in ARRL membership in 2023 is unlikely. 

Does the ARRL represent radio amateurs in the USA??... At the end of 2022, there were just over 769,000 amateur radio callsigns in the United States. The ARRL membership at the end of 2022 was 151,840. This means that just 19.7% of radio amateurs in the United States are members of the ARRL. Back in 2015, that figure was 23.2%.

This seems to me to be a very low figure and it does raise the question about  how any organisation can claim to be a national organisation when they can only attract less than 20% of the total number of radio amateurs in their country.

If we were to look at the UK, there are about 101,000 licences on issue. Due to multiple licences, this in reality means that there are almost 70,000 licensed operators. The RSGB has about 21,200 members which is about 30% of the amateur radio population in the UK. This is in marked contrast to the figure for the ARRL.

UK members of the RSGB receive the RadCom magazine and have to pay £65 per annum ($83) which is similar to the new ARRL fee. Why does membership of the ARRL in the USA seem so poor compared to the RSGB in the UK?

Looking ahead???... With membership falling and a hike in membership, it seems likely that the next few years will be turbulent ones for the ARRL. It currently represents less than 20% of radio amateurs in the USA and that figure seems likely to keep dropping.

If the membership numbers drop a significant amount then that's going to put pressure on the finances of the organisation and it's likely a review of costs will be needed. It's obvious that a full colour printed magazine that is posted out to members is going to be increasingly more expensive and difficult in the future.

As for a solution?... There are a multitude of posts online with people complaining about the ARRL but there seem to be very few solutions. Increasing the membership fees seems like a short term fix but I suspect it's only delaying the inevitable. Sooner or later, they're going to have to look at costs and make cuts.

From my own perspective, I used to be an overseas member of the ARRL in the late 1990's and early 2000's. At the time, information about amateur radio was at a premium and the QST magazine was very informative.

Fast forward to today and we have a multitude of websites, blogs, podcasts, social media, YouTube, etc. The ARRL as a content creator now has to compete with all of these other sources which are mostly free. It's already hard enough to keep up with all of the information that's available online for free without having to pay to look at what's behind a paywall.

Video... In this video, ARRL Director of Marketing and Innovation Bob Inderbitzen, NQ1R, chats with Kevin Thomas, W1DED, host of W1DED WW Ham Radio on YouTube, about the recent survey of members where 20,000 members responded and about the ARRL itself.

In summary... It's in no-ones interest to have a weak ARRL. As can be seen at the recent ITU conference in Doha, some amateur radio bands are under threat and the International Amateur Radio Union (IARU) needs strong member societies to support its work.

I suspect the next few years will be difficult ones for the ARRL as their membership seems likely to drop. They have an increasingly elderly membership base that wants things to stay the same in a world that is rapidly moving to digital.

It seems to me that that the next decade is likely to be a difficult one for the ARRL as they will have to make major changes to stay relevant.

Links...

1) ARRL website

2) Article by K4FMH

Twice around the globe on 21 MHz and 80,000km echoes

Salvadaor, EA5Y near Madrid in Spain recently carried out some interesting tests on the 21 MHz (15m) band at the start of December 2023 and heard his own signal go twice around the world for a total path length of 80,000 kms.

First of all, let's set out the conditions. It's the 5th of December 2023 and the time is 08:30 UTC. Sunrise in Madrid is at 07:22 UTC which was about an hour earlier.

EA5Y is transmitting on 21.022 MHz using 1-kilowatt into a 4-element Yagi beaming at 240 degrees. He is sending a series of single dots and is listening for echoes.

The view from the antenna is shown above and 240 degrees is to the left of 'WEST' and should be close to 'VK2 long path'. There are mountains in the distance but they are some way off and EA5Y probably has a nice low angle of radiation from this antenna at this height.

Echoes... This is the audio plot from Salvador...

Going from the left...

1) He has a backscatter signal at 25-milliseconds which is too short for the human ear to separate from the initial dot.

2) The signal travels around the world and arrives back in Spain 40,000kms later.

3) The signal continues and goes around the globe a second time and arrives back 80,000kms after initially setting off.

Here are some interesting observations....

a) Salvador tried beaming to the north-east in the opposite direction and the echoes were much weaker. He wonders if the path was skewed? i.e. it's not as simple as the map at the top of the post would suggest.

b) He also tried listening to an online receiver based in New Zealand on the 2nd of December and this was 40kms from his antipodal point. You can hear the audio below...

And this is how it sounds... pic.twitter.com/4h62Wc06Kf

— Sal EA5Y (@_EA5Y) December 2, 2023

You can clearly hear the signal reaching New Zealand for the first time at 20,000 kms and then going around the globe again to arrive back in New Zealand again at about 60,000 kms.

No doubt there is some antipodal focusing going on here and multiple paths and options appear for the signal instead of the usual short path / long path options.

As for the propagation mode, it's obvious via the F2 layer but there is probably some chordal hop involved with the signal going between different points of the ionosphere without needing a reflection off the ground.

We often see reports of long path echoes but it's interesting to see a report of a signal going around the world twice.

Further tests??? ... The obvious question is just how many times does the signal travel around the world? Are there times of the day when the signal is ever present going around the world multiple times before conditions change and the path breaks?

I wonder if it would be possible to decode some of the 2nd, 3rd, 4th, etc echoes with a digital signal? Something like the MSK144 meteor scatter mode using fast decode? Some other mode? 

Is there some weak signal mode that is capable of decoding your own weak echoes without relying on looking at ticks on an audio plot?

Maybe there isn't but I'm just putting it out there in case someone wants to investigate.

Previous posts...

1) Long path echoes on the 24 MHz band (VO1FOG) - Dec 2021 

2) Long Path Propagation on the 17m HF band (VO1FOG) - Dec 2022 

Video - From Signals to Solutions: Amateur Radio's Impact on the Future of Engineering

The IRTS president Enda Broderick, EI2II recently gave a presentation to Engineers Ireland about amateur radio titled 'From Signals to Solutions: Amateur Radio's Impact on the Future of Engineering and STEAM (Science, Technology, Engineering, Arts, Maths)'

It was described as follows... "IRTS President and engineer Enda Broderick explores how the modern version of Amateur Radio can impact the interest of future generations to look at Engineering differently. The hobby has all the elements associated with STEAM and can be used to develop a creative and fun environment to develop within."

The video embedded above is aimed at those who might have an interest in science and technology but don't know much about amateur radio.

3275km opening on 144 MHz between Madeira Islands and Denmark - 17th Dec 2023

There has been some remarkable tropo conditions in Europe over the last few days with some stations completing contacts on the 144 MHz band in excess of 2000kms. 

One of the longest contacts was that shown above... an amazing 3,275 km contact using FT8 between Thomas, OV3T in Denmark and Stefan, CT9/OM3RG on the Madeira Islands. See report from Stafan at the bottom of the post. Thomas reports using 700-800w into a 2 x 11-element Yagi on a 18m tower. 

As can be seen from the map above, it is mostly a sea path but it does have to cross some land.

Bernd, DF2ZC in Germany also reports working CT9/OM3RG and the distance for this 2m contact was 2,818 kms. Bernd reports using EME power to 4 x 18-element M2 Yagi. Bernd also reports that the path had to cross over 1800m high mountains in the north-west of Spain. 

Propagation Mode???... The long path over the sea would suggest it was one of the marine ducts that we have seen in the past resulting in really long distance contacts. The obstructed path however from DF2ZC to the Madeira Islands would suggest an elevated duct. Was it a combination of a marine duct near the surface and an elevated duct?

The tropo forecast by Pascal, F5LEN certainly suggests a good sea path for some areas.

I think some people will have their own ideas but I don't think anyone can be certain on this one.

Update: See bottom of post for another propagation map.

Link... For examples of other long distance contacts on the 2m band, see my 144 MHz page.

Addendum 1: Thanks to Stefan, CT9/OM3RG for sending on this additional information.

Stefan reports that he was using 100-watts from an ICOM IC-9700 into 2 x 9-element LFA Yagi.

He reports that he worked as many stations as he could with his 100-watts. He heard lots of other stations from Germany (DL), Belgium (ON) and Netherlands (PA) but they couldn't hear him.

This is a list of stations that Stefan worked on the 17th & 18th of December 2023. 3000km+ stations in red, 2500km+ in orange. CW in bold.

20231217 7:02 F6DBI IN88IJ FT8 2085

20231217 9:36 MW0AXA IO81FQ FT8 2371

20231217 9:37 GW7SMV IO81LN FT8 2378

20231217 9:38 G4CBW IO83UB FT8 2546

20231217 9:40 EI9KP IO54MB FT8 2450

20231217 9:44 G8JLY IO82WG FT8 2480 

20231217 9:45 G0PQO IO92UA FT8 2365

20231217 9:46 M0PNN IO82TS FT8 2516

20231217 9:49 G4FUF JO01GN FT8 2530

20231217 10:12 F6EGD IN88HR FT8 2110

20231217 10:14 G4EZP JO01GN FT8 2530

20231217 10:25 G8HGN JO01FO FT8 2530

20231217 10:28 EI8KN IO62IE FT8 2296

20231217 10:30 F6HRO IN88JQ FT8 2114

20231217 10:32 G7GXK IO90IS FT8 2378

20231217 10:40 G8TTI IO81WM FT8 2408

20231217 10:42 2E1EMK IO91BI FT8 2404

20231217 10:47 G4BNM IO93EV FT8 2644

20231217 12:04 G4ELW IO81MC FT8 2337

20231217 18:21 G4ZFJ JO01HO FT8 2538

20231217 18:22 CT7AUS IM58HT FT8 968

20231217 18:24 G0LGS IO81WV FT8 2444

20231217 18:25 G8GON IO80HP FT8 2281

20231217 18:27 G4KWQ IO92AQ FT8 2523

20231217 18:28 M0BUL IO82NG FT8 2450

20231217 18:29 G4NBS JO02AF FT8 2564

20231217 18:30 M6JAY IO90HV FT8 2387

20231217 18:30 G7RAU IO90IR FT8 2377

20231217 18:31 G4DCV IO91OF FT8 2442

20231217 18:31 G0BIX JO01CI FT8 2498

20231217 18:32 G0ODR JO02OP FT8 2651

20231217 18:32 G0JDL JO02SI FT8 2642

20231217 18:33 PA4ZP JO21RK FT8 2766

20231217 18:38 G1OJS IO90JU FT8 2391

20231217 18:43 G0LTG IO81RF FT8 2367

20231217 18:44 G6HIE JO00DW FT8 2467

20231217 18:47 PA3BIY JO22HB FT8 2768

20231217 19:22 G3TKF IO81SJ FT8 2386

20231217 19:24 M0CFV IO91UM FT8 2489

20231217 19:25 G4ZTR JO01KW FT8 2577

20231217 19:28 G7WIR JO01BJ FT8 2497

20231217 19:28 G3XDY JO02OB FT8 2602 

20231217 19:29 G3XDY JO02OB FT8 2602

20231217 19:31 F6EAS IN98LV FT8 2235

20231217 19:32 G4GFI IO91VH FT8 2475

20231217 19:34 OV3T JO46CM FT8 3275

20231217 20:09 GW4SHF IO82HP FT8 2466

20231217 20:11 G4RGK IO91ON FT8 2471

20231217 20:13 PA2M JO21IP FT8 2741

20231217 20:16 G4AEP IO91NJ FT8 2453

20231217 20:19 G4KPZ IO92WK FT8 2575

20231217 20:21 G0JJG JO02ME FT8 2605

20231217 21:42 PA2CHR JO32DB FT8 2854

20231217 21:48 DG6JF/P JO33QN FT8 3017

20231217 21:50 PA3DZL JO21LS FT8 2763

20231217 22:08 G4DHF IO92UU FT8 2605

20231217 22:10 PA3BIY JO22HB FT8 2768

20231217 22:20 G0LTG IO81RF CW 2367

20231217 22:21 G4DHF IO92UU CW 2605

20231217 22:27 G0LTG IO81RF CW 2367

20231217 22:42 ON4KHG JO10XO FT8 2626

20231217 23:21 G0GMB IO92NB FT8 2511

20231218 6:37 F6KHM IN78RJ FT8 2028

20231218 6:39 G4FUF JO01GN FT8 2530

20231218 6:46 F5DQK JN18GR FT8 2413

20231218 6:50 G4EZP JO01GN FT8 2530

20231218 6:51 F6GNR IN97FD FT8 2069

20231218 6:53 EA1M IN53TI FT8 1399

20231218 6:55 G4RRA IO80BS FT8 2272

20231218 7:24 G4MKF IO91HJ FT8 2431

20231218 7:37 ON4KHG JO10XO FT8 2626

20231218 7:46 ON4KHG JO10XO FT4 2626

20231218 7:55 G3XDY JO02OB FT4 2602

20231218 8:36 M0VXX IO90 FT8 

20231218 8:40 EA7JCR IM67WK FT8 1129

20231218 8:47 G3WZT IO90UX FT8 2443

20231218 8:49 G4DDK JO02PA FT8 2603

20231218 8:52 M0CKM IO90QT FT8 2414

20231218 8:54 G4FSG JO02PC FT8 2610

20231218 8:55 EA1YV IN52OC FT8 1268

20231218 8:59 G3WZT IO90UX CW 2443

20231218 9:02 M0CKM IO90QT CW 2414

20231218 9:10 EA1DFP IN53XI FT8 1416

20231218 9:12 G6HIE JO00DW FT8 2467

20231218 9:20 EA1CCM IN52QG FT8 1291

20231218 9:21 G3ZSS IO90NU FT8 2406

20231218 9:23 G3SJX IO91LC FT8 2420

20231218 9:44 DF7KF JO30GU FT8 2785

20231218 9:45 OQ4U JO20KV FT8 2696

20231218 10:01 PA1BVM JO21RO FT8 2778

20231218 10:15 PA3DOL JO22MT FT8 2845

20231218 10:30 PA3DOL JO22MT FT8 2845

20231218 10:35 G0JJG JO02ME CW 2605

20231218 10:47 G4CKS IO91VL FT8 2489

20231218 10:59 DF2ZC JO30RN FT8 2818

20231218 11:45 DL8YE JO32TC Q65A 2929

20231218 13:11 G4HSK JO01FS FT8 2544

20231218 13:18 G4BWP JO02FH FT8 2590

20231218 13:19 G0LQI IO80SP FT8 2319

20231218 13:23 PA0CAB JO22DA FT8 2748

20231218 13:34 PA3DOL JO22MT FT8 2845

20231218 15:38 DL1YDI JO42FA Q65A 2969

20231218 16:02 DM1CG JO30GU Q65A 2785

20231218 16:26 DM1AC JO30IV Q65A 2797

20231218 18:46 PA3BIY JO22HB FT8 2768

20231218 18:48 PA3FYC JO31AF FT8 2783

20231218 19:11 PA5Y JO21VO Q65A 2795

20231218 19:39 DL5EBS JO31NH Q65A 2848

20231218 19:54 ON4CLQ JO11SE FT8 2647

20231218 20:09 F5RZC JO10JG FT8 2539

20231218 20:50 ON4MU/P JO20ET FT8 2663

20231218 21:01 DL5EBS JO31NH FT8 2848

Addendum 2: PA3AUC supplies the following chart which suggests that the opening was due to an elevated duct at 500-750m.

Meteor scatter experiment with the 2023 Geminid shower

In this post, I'll outline how I used an amateur radio beacon 500kms away to find the peak of the 2023 Geminids meteor shower and what else I noticed.

Introduction... Back in 2022, a new radio beacon called GB3MBA was put on air on the 50 MHz band and its primary purpose was carrying out meteor scatter experiments. Located near the town of Mansfield in the centre of England, the beacon runs 75-watts into a small Moxon antenna which beams straight up.

Unlike most amateur radio beacons, this one is basically a carrier that is on nearly all of the time which is exactly what is needed for meteor scatter experiments. The main coverage area is the UK itself but as I'm 502 kms from the beacon, I'm close enough for it to be of use.

I expected that most of the signals that I would hear would be from meteors burning up over Wales and would be arriving at my location about 20 degrees above the horizon.

Experiment Objectives... This is what I wanted to do...

• Carry out an experiment as a 'proof of concept', take measurements, gain experience and see how I could improve on it.
• Take 'hard measurements' with real data as opposed to just forming an opinion.
• See if I could plot and find the peak of the 2023 Geminid meteor shower as a form of 'citizen science'.

Methodology & Equipment... For the previous few days before the peak, I was listening to meteor bursts from the beacon to establish the best method to carry out the experiment.

Radio... I was using an old Kenwood TS-690 amateur radio transceiver which still works fine and is pretty sensitive. I tuned it to 50.408 MHz and set the mode to CW. It drifts a few Hz with the changes of temperature in the shack but it was fine for this experiment. I just needed to be careful to make sure I was always on frequency.

Antenna... In the run up to the experiment, I used a 2-element Yagi in my attic beaming 120-degrees (east-south-east) to get ready. This was beaming about 45 degrees away from the beacon and being indoors, it wasn't optimum. Just before the experiment, I built a vertical T2LT (flowerpot) half-wave antenna and mounted it about 6-metres above the ground. It had a clear view of the sky towards Wales and the beacon.

Software... I used the SpectrumLab programme to look at the audio spectrum so that I could see any bursts and pings of signal. Under the 'Quick Settings', I used Slow Morse Reception ("QRSS") and I then selected 'Slow CW, 30 sec/dot'. 

I knew it wasn't practical to look at a screen for hours on end. At this setting, the audio spectrum is about 30 Hz wide and it takes about 1h 20m for the signals to drift from right to left across the screen. What this meant in reality was that I could look at the screen every 60-80 mins, count the signals on the screen and record the number of pings and bursts.

What to record?... I knew whatever I did, it had to be consistent for the observing period. I decided to use the number of signals seen in a 30-minute period. If it was a long burst or a short ping, I counted it as one signal. 

This raises the obvious question... should I count the number of pings and bursts, should I record the strong signals versus the number of weak signals? The problem is where do I draw the line? I knew I'd see long bursts, short pings and everything in between. It was the same for the signal strength... what's a 'strong signal'? 

I decided I just wanted 'hard data'. Was there a meteor scatter signal present on the screen... Yes or No. It's simple and there's no ambiguity.

Time period... For the experiment, I counted the number of meteor scatter signals from 17:30 UTC on the 14th of December to 22:00 UTC on the 15th of December 2023...a period of 28 hours and 30 minutes. This time frame coincided with the predicted peak of the Geminid meteor shower.

Results... This is the chart that I generated for the 28.5 hour period.

The recording period starts at 17:30 UTC on the 14th of December when the Geminid constellation and radiant point would be just above the horizon. I'll break down the chart in more detail below but the key thing to note is the peak at about 20:00 UTC on the 14th of December.

I had intended to stop recording early in the morning of the 15th but I was wondering if the peak was really the peak? Would there be another peak 24-hours later when the radiant point would be at the some position in the sky? As you can see, there was no peak 24-hours later. I had actually recorded the peak of the Geminids on the 14th.

Results - Time Frame - 17:30 UTC 14th Dec to 05:30 UTC on the 15th of December... The peak, the dip and the highest radiant...

The first 12-hours is shown above in more detail.

The start... I did a search on Google and it said that the constellation Gemini would rise above the horizon in London at 17:23 UTC. I'm 8.5 degrees west which means it would be 33 mins later... 17:56 UTC. The mid point might be say 17:39 UTC? I found another website which said that the radiant point would rise around 16:07 UTC??

This is further complicated by the fact that we're really looking at a time when meteors from radiant point in the Geminids would be hitting the atmosphere 100kms about Wales? I think 17:30 was a good enough time to start.

The peak... Between 19:00 and 20:30 UTC, I had counts of 15, 19 & 21 for each of the 30-minute intervals.

This is a screenshot I took during this period.

First, I'll explain what you are looking at. The vertical axis is a 30 Hz wide segment of the audio spectrum. The screen is moving from right to left and the white dotted lines are the 5-minute time intervals.

If I was hearing the beacon signal directly, it would be a solid yellow line running from right to left across the centre of the screen.

What you are looking at are the pings and bursts of meteor scatter signals which are spread out across the audio spectrum due to doppler shift.

Prior to the shower, I had seen that the peak was expected at 19:30 UTC on the 14th of Dec. Looking at my screenshot, I think the peak of the 2023 meteor shower occurred between 19:55 and 20:20 UTC on the 14th of December.

The dip??... I did make a note of how weak the reflections were from 22:30 and 00:00 UTC and this can be clearly seen in the chart above. 

As the meteor shower radiant moves slowly across the sky, the angles between the transmitter, receiver and the trails of the meteors will change. At some points, the meteor trails will be parallel between my location and the beacon and at other points, the trails will be perpendicular.

I suspect the dip is due to the geometry of the meteor trails but I'm not sure. It could also be just a statistical error. I would need to repeat the observations on several days around this time period to see if it repeats.

Maximum elevation... At about 01:30 UTC, the radiant point was supposed to be at its highest elevation which was about 71 degrees above the horizon.

Before the experiment, I was wondering if this mattered? Would there be some sort of peak when the radiant peak was at its highest point in the sky? The answer seems to be no, there is no peak.

Results - Time Frame - 01:30 UTC to 11:00 UTC on the 15th of December... The daily morning peak...

When it comes to random meteors entering the atmosphere, the best time for signals tends be around 6am local time. This is because the speed of the earths rotation is added to the speed of the meteors resulting in more energy to dissipate.

This enhancement can be clearly seen in the chart above. It increases after 02:00 UTC and decreases after 10:00 UTC. For me at least, it seemed to be an eight hour window.

The converse is also true. At 6pm local time, the speed of the earth's rotation is subtracted from the original speed of the meteors.

This means that the peak of the 2023 Geminids at about 20:00 UTC happened just two hours after 6pm for me which isn't a great time.

As I was looking at the original chart with the 28.5 hour display, I realised that I was looking at two peaks but both were completely different. One is a fixed peak and the other is a variable peak.

The fixed peak was the peak of the Geminids at about 20:00 UTC on the 14th of December. That's fixed, the peak is the peak.

The morning peak however will depend on where you are. Somewhere in the world, the peak of the Geminids meteor shower will coincide with 6am local time. That turns out to the western half of the Pacific. Anyone in say Hawaii, Alaska, Korea, Japan, east China and the Philippines should have seen some very good meteor bursts and pings. That is of course conditional on having the radiant point above the horizon and that will depend on the location.

Results - Time Frame - 09:00 to 22:00 UTC on the 15th of December... This is the last 13 hours of the plot in more detail...

The radiant point for the Geminids sets about 10:00 UTC and a drop in numbers can be seen. The signals from about 10:00 to 17:30 UTC are random meteors and are not Geminids as the radiant point is below the horizon.

You can see it was particularly poor from 16:30 to 17:30 UTC. Then the Geminids radiant point comes above the horizon and the numbers increase again.

Other observations... Aircraft Scatter... I've seen plenty of aircraft scatter on signals before but I was really surprised to see it on a signal from 500kms away.

These can be very easy to miss. On the QRSS 3 setting, these appear as almost horizontal lines due to the larger vertical scale and faster scrolling speed. On QRSS 30 as used above, the slant becomes a lot more obvious.

As you can see, the doppler shift is in the region of 5-7 Hz. When I was seeing these signals appear, I would check FlightRadar 24 and sure enough, there was often a large plane to the west of Aberstwyth on the west coast of Wales. This is around the halfway point from the beacon to my location.

This suggests to me that while the GB3MBA beacon is 'beaming straight up', there is plenty of RF heading towards the horizon as well.

You'll notice as well that the trails last for about 90 seconds which should be enough for digital modes like MSK144 or possibly FT4? I'd have no doubt that a lot of those one off FT8 decodes on the 10m and VHF bands that people get are due to aircraft scatter like this.

Additional Notes...

• I couldn't tell if any meteor heard was a Geminid or not for the time the radiant was above the horizon.
• Despite all of the 'streaks' visible on the screen, the signals were actually pretty weak. Many were not audible to my ear and I'd say the strongest signals were probably something like 519. 
• The process that I used was very labour and time intensive. I literally had to set an alarm to wake up every 60-80 mins overnight and take the measurements.
• My resolution was 30 mins which may have limited the resolution in that I couldn't tell if two very close bursts were one or two.

In Conclusion... I think the experiment overall was a success. I was able to see the peak of the 2023 Geminid meteor shower which was from 19:55 to 20:20 UTC on the 14th of December.

I'm sure there is room for improvement but I think this is a useful 'citizen science' project which can be done by anyone with a good receiver and antenna. This method is also easy enough that it's not restricted to those from a radio background. 

Anyone with a serious interest in astronomy and meteor research could do this and consider it as an additional tool. This system works regardless of the weather. While 'visual' amateur astronomers need clear skies, the 'radio' based amateur astronomer can carry on regardless.

It might make an excellent project for an astronomy or radio club and maybe give a presentation to students as part of a STEM outreach programme

I think it proves that GB3MBA is indeed a very useful beacon for meteor scatter research and I think the challenge now is for them to make more people aware of it.

You can tell from the length of this post that this was a deep dive down the rabbit hole for me. As soon as I had one question answered, I thought up of two more additional questions.

The future??.. I'd see these as areas for improvement.

1. My antenna was a vertical half-wave which is omni-directional. I think something like a 3-element Yagi would give me at least 6dB more gain, reduce noise and result in more pings and bursts.
2. My experiment was for 28.5 hours with a resolution of 30 mins. I think in the future, I would use QRSS 3 with a finer resolution of 10 minutes and plot the period around the predicted peak in more detail.

More information...

For more information on the GB3MBA beacon, go to https://ukmeteorbeacon.org/

There is also the BRAMS beacon in Belgium on 49.970 MHz which might be of interest... https://brams.aeronomie.be/