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.

27,300km Long path opening on the 50 MHz band from Italy to Hawaii - 16th Oct 2023

Now that we have reached October and at this stage in the solar cycle, the 50 MHz band is starting to open up with some remarkable paths. This is especially true for stations in the south of Europe.

Riccardo, IZ5BRW in Italy reports a very interesting long path opening on the 50 MHz band on the 16th of October 2023 to Hawaii, a path of about 27,300kms.

IZ5BRW writes... "The opening occurred mainly on Monday 16th Oct. (09 to 11 UTC +/-) and on Tuesday 17th. (8 to 10:30 UTC +/-).

I only worked KH6HI on Monday 16th. There were also other friends able to work the KH6 stations here in Zone 5 – Tuscany.

Tuesday was stronger even though I was not at home to work KH6. My friend Steve IK5MEJ worked 3 different stations on Tuesday 17th., KH6HI – KH6WI – NH6Y.

Anyway, all qsos made in FT8 and Long Path, which is more or less 170° from my qth JN53OP. My setup is FT-5000 + 7L Yagi EF0607X home made + 500W.

It’s a 27,000Km+ path and for me, KH6 was a new one on 6m as well as a new grid and new WAZ!

Albert, KH6HI has already confirmed the qso on LOTW."

Thanks to Riccardo for the report.

Comment & Analysis... As can be seen from the screenshot above, the contact was made with FT8 and the signals were in the region of -9 to -13dB. This is just about audible to the human ear and it would be difficult to have a CW QSO at this signal level. Obviously, those signal levels are not a problem with FT8.

No doubt there were others who made similar long path contacts like this on the day but this one is a good example of what the opening was like and that others should be looking for this path as well. Note the time and beam heading.

As for the mode of propagation, it was probably multi-hop or chordal hop F2-layer.

Sunset in Hawaii was about 18:00 local time or 10:00 UTC. It's no great surprise that the opening was about 30 mins after sunset and the F2 layer would have tilted at this stage to the west of Hawaii. This allows propagation of higher frequency signals and at a lower angle.

The takeaway message from this is to look at the sunset for a region you're interested in working and try beaming long path to see if an opening is possible. 

Links... 1) See my 50 MHz page for examples of other long distance openings on the 6m band.

Madeira HF beacon CS3B destroyed in wildfire - Oct 2023

The radio beacon CS3B on the Portuguese island of Madeira was destroyed in a wildfire on the 12th of October 2023. The image above shows the destroyed radio and what the original ICOM 7200 would have look like. This new radio was only installed in September of 2023

The CS3B was part of the International Beacon Project which is a series of HF beacons operating on 14.100, 18.110, 21.150, 24.930 & 28.200 MHz.

The location of CS3B is shown above off the north-west coast of Africa and it was an ideal location for testing radio propagation on the HF bands to Europe and to North America.

The amount of fire damage to the site was quite extensive as the building housing the beacon was destroyed as well as the antenna as can be seen below.

It's very likely that any traps on the antenna will have been damaged as well by the heat and I suspect the whole antenna will need to be replaced.

The chart above from the Reverse Beacon Network (RBN) site shows the beacon operating on the 12th of October 2023 until it stopped suddenly around 15:00 UTC.

As can be seen from the chart above, the last reception reports were for 14:57 UTC.

Considering the extensive damage to the beacon and building, this HF beacon is likely to be off air for some time.

Link... IARU International Beacon Project

Opening on the 40 MHz band from Ireland to Australia - Oct 2023

I noticed in the last few days that there has been a path open on the 40 MHz (8m) band from Europe to Western Australia in the morning hours.

Here are the WSPR spots from the Irish beacon EI1KNH which is just south of Dublin.

 y-m-d txCall txGrid rxCall rxGrid MHz W SNR drift km
2023-10-18 09:44 EI1KNH IO63ve VK6JR OF76mi 40.014505 20 -29 0 14969

2023-10-16 09:44 EI1KNH IO63ve VK6JR OF76mi 40.014511 20 -21 0 14969
2023-10-16 09:34 EI1KNH IO63ve VK6JR OF76mi 40.01451 20 -21 0 14969
2023-10-16 09:14 EI1KNH IO63ve VK6JR OF76mi 40.01451 20 -20 0 14969
2023-10-16 08:54 EI1KNH IO63ve VK6JR OF76mi 40.01451 20 -26 0 14969

2023-10-15 10:34 EI1KNH IO63ve VK6JR OF76mi 40.014509 20 -33 0 14969

2023-10-09 11:34 EI1KNH IO63ve VK6JR OF76mi 40.014499 20 -29 0 14969
2023-10-09 11:14 EI1KNH IO63ve VK6JR OF76mi 40.014498 20 -22 0 14969
2023-10-09 10:54 EI1KNH IO63ve VK6JR OF76mi 40.014498 20 -23 0 14969
2023-10-09 10:44 EI1KNH IO63ve VK6JR OF76mi 40.014499 20 -25 0 14969

2023-10-08 10:44 EI1KNH IO63ve VK6JR OF76mi 40.014498 20 -24 0 14969

EI1KNH transmits four times every hour using the WSPR mode and the power is about 20-watts into a vertical half-wave antenna. The receiving station was Wayne, VK6JR to the south of Perth in Western Australia. The distance was 14,969kms.

The signals are very weak and they are in the range of -20dB to -33dB. This would mean that they are inaudible to the human ear.

The path seems to have been open on five days from the 8th to the 18th of October 2023. The times range from 08:54 to 11:34 UTC.

Sunset in Perth is about 10:30UTC so it's likely there was some enhancement due to some tilting of the ionosphere. With the solar flux at about 140, the propagation mode may have been multi-hop F2 layer with perhaps some chordal hop as well.

Greece to Australia on 40 MHz... VK6JR also heard the WSPR beacon of Costas, SV1DH in Greece.

y-m-d txCall txGrid rxCall rxGrid MHz W SNR drift km
2023-10-09 08:02 SV1DH KM18 VK6JR OF76mi 40.681494 10 -24 -2 12412
2023-10-09 07:38 SV1DH KM18 VK6JR OF76mi 40.681492 0.01 -28 -1 12412
2023-10-09 07:30 SV1DH KM18 VK6JR OF76mi 40.681492 0.01 -25 -2 12412
2023-10-09 07:26 SV1DH KM18 VK6JR OF76mi 40.681492 0.01 -23 -2 12412
2023-10-09 07:16 SV1DH KM18 VK6JR OF76mi 40.68149 0.01 -21 -1 12412
2023-10-09 07:10 SV1DH KM18 VK6JR OF76mi 40.681491 0.01 -19 -3 12412
2023-10-09 06:58 SV1DH KM18 VK6JR OF76mi 40.681491 0.01 -22 -1 12412

According to the data above, SV1DH was using around 0.01 watts or 10-milliwatts for the majority of his transmissions! The last one was at 10-watts. The distance was 12,412kms. 

In general, the path from the south-east of Europe to Australia is easier as the path is shorter and the signals stay closer to the equator.

In summary... We have seen plenty of other openings on the 40 MHz band between Europe and Australia over the last 12-months. I have details of these in previous posts which are linked from my 40 MHz page.

It's very likely that we will see more openings like this over the next few months. Serious 50 MHz operators should take note of these 40 MHz openings as they suggest that an opening on the 6m band may be possible.