2024 10m QRSS Challenge: - IW0HK beacon in Italy - 8th May

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. On the 8th of May, I got a screengrab of the QRSS signal 'HK' which was sent by the IW0HK/B beacon near Rome in Italy.

Usually, nearly all of the QRSS signals on the 10m band are on 28.1246 MHz and the audio of the signals is about 400-500Hz below the WSPR signals. In this case, the IW0HK beacon was on 28.322 MHz.

In the image above, the fuzzy part of the signal is when it was sending the callsign and locator of the beacon in normal morse code. The QRSS 'HK' part is sent after this.

The beacon runs 1-watt into a vertical five-eight wave antenna.

The map above shows the path and the distance was about 1800kms. The signal was almost certainly via Sporadic-E and it's pretty much the ideal distance for that mode of propagation.

In summary... That brings the QRSS tally so far for 2024 up to 20-callsigns & 10 DXCC.

1) 8th Jan 2024: VE1VDM - DXCC #1
2) 10th Jan 2024: VA1VM
3) 15th Jan 2024: G0MBA - DXCC #2
4) 15th Jan 2024: G0PKT
5) 15th Jan 2024: AE0V - DXCC #3
6) 16th Jan 2024: RD4HU - DXCC #4
7) 16th Jan 2024: W1BW
8) 17th Jan 2024: OH5KUY - DXCC #5
9) 18th Jan 2024: TF3HZ - DXCC #6
10) 6th Feb 2024: VA3RYV
11) 16th Feb 2024: IK2JET - DXCC #7
12) 16th Feb 2024: N8NJ
13) 21st Feb 2024: PY3FF - DXCC #8
14) 26th Feb 2024: VE6NGK
15) 27th Feb 2024: NM5ER
16) 28th Feb 2024: VK4BAP - DXCC #9
17) 2nd Mar 2024: WA1EDJ
18) 5th Mar 2024: FR1GZ/B - DXCC #10
19) 30th Apr 2024: IK1WVQ
20) 8th May 2024: IW0HK/B

Mystery opening on 28 MHz in the middle of the night - 21st Mar 2024

Robbie, EI2IP reports that there was an unusual opening on the 28 MHz band on the 21st of March 2024. At the moment, the 28 MHz band closes here in Ireland at about 21:00 UTC which is about two hours after sunset. 

Robbie reports working FM4LV in Martinique in the Caribbean on the 28 MHz (10m) band at around 00:49 UTC on the 21st of March which is about six hours after sunset. This is very unusual and raises the question what was the propagation mode?

The general expectation is that all F2 layer propagation should have disappeared six hours after sunset.

FM4LV was on FT8 and there were loads of stations to the west of him reporting his signal. None of these are of interest as they're just the usual F2. These are the stations to the east that heard FM4LV after 00:00 UTC...

Rcvr Band Mode Distance Time (UTC)
EA7DZ 10m FT8 6100 km 00:55:14 (Spain)
CN/TANGER 10m FT8 5938 km 00:50:00 (Morocco)
EI2IP 10m FT8 6217 km 00:49:11 (Ireland)
EA8RH 10m FT8 4791 km 00:39:42 (Canary Islands)
EA8AXB 10m FT8 4920 km 00:23:14
EB7FBJ 10m FT8 6091 km 00:15:11

The paths to the far south of Spain, Morocco & the Canary Islands are well to the south and are much more likely to have propagation at 28 MHz, even well after dark. The question is how was there a path to EI2IP in Ireland at 52 deg north?

That brings us to the good old dependable Sporadic-E.

Q. How did the F2 layer propagation reach that far north? Answer - An extra hop provided by Sporadic-E.

Q. How is any unusual path possible? Answer - Sporadic-E.

Q. "The propagation chapter in my ARRL handbook doesn't explain how I made a contact?" Answer - Sporadic-E.

Q. Why did my coffee go cold? Answer - Sporadic-E.

OK, I lied about the last one but the point being is that we seem to perhaps use Sporadic-E as an explanation a bit too often. In this case, the opening was at about 1am in the morning in March, not a time noted for Sporadic-E as the Sporadic-E season doesn't start properly until mid-April and it's usually during the daylight hours.

The map above shows the parts of the earth in sunlight and shadow around the time of the opening.

For EI2IP, it's in the middle of the night and six hours after sunset. For FM4PV, it was about two and a half hours after sunset.

When I took a screen grab of this image, I couldn't help notice that the moon was almost directly above Martinique which got me thinking. If the moon is visible to both stations then signals must be reflected off the surface of the moon even at 28 MHz?

In this case, I think the combined antenna gain was probably too low for moon bounce and the answer is probably that the signals came off a layer in the ionosphere. As for the exact propagation mechanism?

When I looked at an online propagation map, it suggested that the path was impossible at that time of day so it's a bit of a mystery.

Australian stations heard on 28 MHz WSPR over a 4-week period - Jan & Feb 2024

Conditions on the 28 MHz band have been really good for the last few weeks as can be seen from the map above which shows all of the WSPR stations that I heard from the 23rd of January to the 19th of February 2024.

In total, there are 1334 individual stations which is a lot for a mode like WSPR which after all is just a beacon mode and not designed to make two way contacts. There are a lot of interesting paths in the map but the one I will focus on here are the ones to Australia.

My location in north-west Europe is in the region of 15,000 to 17,500 kms from Australia. While it's not exactly the 'other side of the planet' i.e. 20,000kms, it's still a long way for a 28 MHz signal to travel.

In total, I heard 28 stations from Australia over the 4-week period on 28 MHz. The list is shown below...

local   y-m-d txCall txGrid rxCall rxGrid MHz                 W SNR drift kms
2024-02-15 13:58 VK6TQ OF76of EI7GL IO51tu 28.126101 20 -16 0 15139
2024-02-01 13:22 VK6MJV OF77 EI7GL IO51tu 28.126135 10 -27 0 15028
2024-01-31 12:56 VK6LDL OF77vx EI7GL IO51tu 28.126201 5 -20 1 15047
2024-02-13 12:34 VK6HQ OF87av EI7GL IO51tu 28.126028 0.2 -26 0 15071
2024-02-06 12:26 VK6CRO OG65ud EI7GL IO51tu 28.126137 0.2 -24 -2 14335
2024-02-13 12:22 VK6BMT OF78ve EI7GL IO51tu 28.126038 0.2 -25 0 15031
2024-02-03 07:58 VK5ZBI PF95ga EI7GL IO51tu 28.12613     10 -27 0 16794
2024-02-09 07:54 VK5ADE PF94hj EI7GL IO51tu 28.126084 20 -22 0 16849
2024-02-01 08:54 VK4TMT QG62 EI7GL IO51tu 28.126097 0.1 -18 0 16894
2024-02-01 08:56 VK4SA QG62 EI7GL IO51tu 28.12615     0.2 -26 0 16894
2024-02-19 08:58 VK4PK QG62qi EI7GL IO51tu 28.126134 0.2 -19 0 16923
2024-02-14 08:42 VK4NE QG62nj EI7GL IO51tu 28.126133 0.1 -26 -1 16909
2024-02-19 09:00 VK4LA QG62 EI7GL IO51tu 28.125991 0.2 -26 0 16894
2024-02-01 08:42 VK4JBY QH30jq EI7GL IO51tu 28.126168 0.2 -28 -3 15801
2024-02-19 08:42 VK4EKA QG62ap EI7GL IO51tu 28.126177 1 -7 0 16838
2024-02-19 08:58 VK4BA QG62 EI7GL IO51tu 28.126196 0.2 -20 0 16894
2024-02-03 09:10 VK4AGR QG53wg EI7GL IO51tu 28.126187 0.2 -27 0 16768
2024-02-04 09:18 VK3VJP QF12 EI7GL IO51tu 28.126022 0.2 -20 0 17273
2024-02-16 08:06 VK3KCX/1 QF22qd EI7GL IO51tu 28.12603  5 2 -14 0 17449
2024-02-18 09:46 VK3CWF QF22ke EI7GL IO51tu 28.12606 5 -25 0 17415
2024-02-01 08:18 VK3AMW QF22ir EI7GL IO51tu 28.12607  5 5 -16 0 17362
2024-01-30 08:52 VK2XSM QF56og EI7GL IO51tu 28.12605     1 -19 -1 17419
2024-02-06 08:12 VK2VJ QF57vb EI7GL IO51tu 28.12604     1 -21 1 17373
2024-02-01 08:22 VK2QQ QF55gt EI7GL IO51tu 28.126209 5 -23 -2 17427
2024-02-12 09:20 VK2KYB QF56lf EI7GL IO51tu 28.126085 5 -27 0 17410
2024-02-19 09:52 VK2HL QG56 EI7GL IO51tu 28.126156 0.2 -25 0 16406
2024-02-16 08:06 VK2GDF QF67ch EI7GL IO51tu 28.126142 0.2 -14 4 17369
2024-02-01 07:56 VK1KF QF44mr EI7GL IO51tu 28.126049 5 -22 -3 17445

The ones I find of special interest are the low power stations which are in bold running output powers of 100 to 200 milliwatts. On my side, I'm just using a simple cheap half wave vertical CB type vertical to hear all of these stations.

It's just an example of how good conditions are now on 28 MHz at the peak of the sunspot cycle and is in marked contrast to the minimum a few years ago.

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/

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

QRSS signals heard on 28 MHz - 1st Nov 2022

Every day, I leave my HF radio on the 28.1246 MHz to listen for WSPR signals. My PC then decodes these and sends the reception reports up to WSPRNet website for others to see.

The QRSS (very slow morse code) band is just a few hundred Hz below the 10m WSPR band and I noticed in the WSPR waterfall that two QRSS signals were present so I had a look.

The image above shows the QRSS signals that I was hearing over a period of about 20-25 minutes on the 1st of November 2022.

VE1VDM in Canada and G0PKT in the east of England had reasonable signals and they were the two I had noticed initially. G6GN in England is also present but quite weak. There are other very weak QRSS signals as well but I was unable to ID these.

The locations of the relevant stations are shown on the map below.

VE1VDM in Nova Scotia is 4000kms from my location and is easily explained as it's an ideal one F2 layer hop away on 28 MHz.

The signals from G6GN at 400kms and G0PKT at 650 kms are not so easily explained. If it was the Summer months then we might think it was Sporadic-E but, this was the first of November AND G0PKT is pretty much there all of the time every day when the band is open.

I suspect that I am receiving these signals via F2 layer backscatter. In the past (pre digital days), backscatter signals were pretty much buried in the noise with the SSB and CW modes. Now however, WSPR has no problem decoding signals that are 20dB below the noise level and I can see QRSS signals which are in the region of -15 to -20dB.

I think a lot of those 'close in' signals that we are now seeing on WSPR or FT8 on 28 MHz are in reality via backscatter.

You can see from the map above all of the WSPR stations I heard on 28 MHz on the 1st of November. Meteor Scatter? Forward scatter via Sporadic-E? I'm opting for F2 layer backscatter.

I'm using an omni-directional vertical on 28 MHz so I can't beam headings. Maybe someone else wants to do some tests? See which direction those 'close in' signals are strongest. The direct path OR beaming in some other direction at a potential back-scatter point?

Bogus FT8 spots from DS3SHI on 28 MHz

Nearly anyone in Europe transmitting on FT8 on 28 MHz in 2020 will have been spotted by DS3SHI who is supposed to be in South Korea. This is the FT8 coverage for a station in the UK on 10-metres on the 18th of August 2020.

The first impression is that the UK station is being heard by other stations around Europe and by DS3SHI in South Korea. However, that is not the case and the DS3SHI spots are bogus.

A search on Google will show that other stations have been caught out by this and they believed that their FT8 signal on 28 MHz was reaching South Korea.

So where is this bogus DS3SHI station???

There was a very good Sporadic-E opening in Europe on the 29th of April 2020 and I made a record of the FT8 reception map for DS3SHI on 28 MHz. 

Notice how there are so many European stations and there is nothing in China, South Korea or Japan? Another tell-tale sign that this station was not in South Korea and was located in Europe.

If we take a closer look at the map for Europe then you'll notice a large cluster in the east of Germany.

I've added in Yellow shading slowing the 'skip' zone which is largely free of stations with a doughnut of stations beyond that. From this, we can deduce that DS3SHI is in the southern part of east Germany.

So we can zoom in a bit further and you can see the concentration of stations. The centre of this concentration is somewhere west of the city of Chemnitz.

Over the Summer months, I have checked the FT8 map on 28 MHz for DS3SHI and I kept a record of the stations that were heard at 0dB or stronger. The approximate location of these are shown below with the three highest signal levels shown as well.

The whole area seems to be quite hilly so it may be possible to be close to DS3SHI but be quite weak if there was a hill in the way. However, it seems likely that this DS3SHI station is located near the small city of Zwickau.

As for why? Why is someone in Germany using a callsign (DS3SHI) and locator (PM48si) for South Korea? Is it someone using an online SDR receiver? Is DS3SHI even a real call sign? 

The FT8 spots on 28 MHz that this person generates serve no useful purpose and just misleads people. As far as I can tell, this person is only listening on 28 MHz and is not transmitting.

Hopefully if people search Google for the DS3SHI call sign in future, they will find this blog post and discover that the FT8 reports from DS3SHI are bogus.

Update - 25th Aug 2020: Just after this post appeared, it was verified that the spots from DS3SHI were coming from an IP address in Germany. All spots from DS3DHI have now been blocked from the PSK Reporter site.

Calendar for F2 openings on the 11m and 10m bands

For anyone using the 27 MHz to 29 MHz part of the spectrum, propagation is an important subject especially if you want to get work stations around the world. In general, the two main modes of propagation for the 11m and 10m bands are Sporadic-E mainly during the Summer months and F2 for the rest of the year.

In this post, the charts deal just with F2 and what parts of the world are likely to be heard at certain times of the day throughout the year.

It should be noted that this is a general guide. It is highly dependent on where we are in the 11 year Solar Cycle and what the Solar flux is. Usually for stations in North-West Europe, the Solar flux needs to be about 80 or above to start getting openings. North-South paths are more likely and the East-West ones appear with higher flux levels.

The big variable in this is Sporadic-E. This occurs mainly during the Summer months but is present during most months to a certain degree. This can allow stations in the UK for example to get into the Mediterranean on Sporadic-E and then via F2 into South Africa. Expect the unexpected on 10 metres.

This map shows various parts of the World numbered and the charts are based on propagation from the UK and Ireland.

The charts below show the times of day those are might be heard at various time of the year.

Interesting opening to the USA on 10m - 27th June 2018

When I checked the PSK reporter this morning, I noticed that I had heard one lone signal on FT8 on 28 MHz from the USA overnight. It turned out to be NF3R in Pennsylvania who was heard at 2:54am local time here.

As can be seen from the chart above, NF3R was being heard all across the USA. The interesting thing is that I was the only station in Europe to hear NF3R in the early hours of the 27th.

At 5156 kms, it was probably three Sporadic-E hops across the Atlantic. I guess that's the thing with Sp-E, you can never tell when and where it will open to.

FT8 on 28 MHz... Mon 14th May 2018

Another day full of FT8 signals on the 10 metre band. As such, it was pretty similar to previous days with some slight differences.

It opened to South America again but only to Brazil this time. A cluster of stations from the centre of Asiatic Russia came through.

Lots of signals from Europe again via Sporadic-E...

There was an opening on 50 MHz as well and I heard the beacon in Denmark. I also heard the Danish beacon on 40 MHz which was interesting considering that this is in the new Irish allocation of 30 to 49 MHz.

Over the 24 hours, I heard 583 separate stations in 52 countries.

Low Pass Filter for the 10m & 11m Bands

Another one from the archives :o). This is a design for a low pass filter for 29 MHz and would be suitable for anyone on the 28 MHz or 27 MHz bands who needs a filter to reduce harmonics. This is especially valid for anyone using a low powered radio to drive an external amplifier. e.g. Amplifying  4w to say 50-100w.

Coils...12 SWG wire. 6 turns. 8mm internal diameter. Coil length 19mm.

Capacitors...High Voltage ceramic or Mica. 110pf Cap is 100pf and 10pf in parallel.

A suitable enclosure might be a diecast box with the filter built on copper clad board. Note the screen which can be made from the pcb material as well. If you can live with a slightly lower performance in terms of filtering, you can omit the internal screens but make sure you put it in a metal box.

FY5KE worked on 10 metres

I had a listen to the 10 metre band late this afternoon and I noticed some weak cw beacons around 28.204 / 28.205 MHz. They were very weak but I could just make out the N3 callsign and the FN in the locators which meant the band was open to North America. Some F2 propagation at last!

I had a look on the DX Cluster and it was quiet enough. I noticed that FY5KE had been spotted on 28.030 MHz. When I listened, sure enough he was there but he was very weak. He was calling CQ a lot so it wasn't like he had a pile up.

I heard EI4KN call and work him with ease. Ronan is in Cloughjordan on the Tipperary / Offaly border, about 120kms to the north. That's a nice distance for a direct path on 10m. I don't believe it was backscatter as the band wasn't that good.

I had a look around the band and it was pretty quiet. Went back to 28.030 MHz and just left the rig there. After about 10 minutes, he came up out of the noise and I worked him first call with about 50 watts.

My first QSO on 28 MHz since I put the antenna up back in mid-November. It was also my first contact on 28 MHz since October 2012.

It was only later that I realised that FY5KE is actually at the Space Centre in French Guyana.

I had a look around the band and it seemed dead. I put the rig on WSPR and FY5KE popped up there as well.

It was hardly a huge opening but interesting all the same.