October 01, 2017

QRP Labs U3B and an update on my U3S

Last edited:

This is Hans Summers G0UPL:

Photo taken by PA7MDJ at HAM RADIO 2017 in Friedrichshafen

Hans is the designer and developer of amateur radio kits like the already legendary standalone Ultimate3S (U3S) 200mW WSPR transmitter. The kits are sold through his company QRP Labs. Previously I've already written some blog posts about the U3S, of which I've built one myself, and of which I'm an extremely happy user! I met Hans at the QRP Labs booth at HAM RADIO 2017 in Friedrichshafen, and had the pleasure to have a chat with him. We all have our ham radio heroes, Hans is definitely one of mine.

This is the QRP Labs U3S:

U3S as built by PA7MDJ

And this is a prototype of the new QRP Labs U3B:

Photo taken by PA7MDJ at HAM RADIO 2017 in Friedrichshafen

The U3B basically is a miniature version of the U3S and was designed by Hans mainly to be used as a HF WSPR tracker payload for High Altitude Balloons. The U3B currently is still in its test phase, and the past few months about 9 test flights have been done. Most of the test flights were launched by well known WSPR balloonist Dave VE3KCL from Canada. I managed to catch the WSPR signals of two of the balloon test flights, the U3B-2 and the U3B-8.
The miniature size and the almost weightless SMD components make this a very lightweight payload ideal for single "party balloon" WSPR flights. The power of the U3B will be in the range of 10-20mW, and the current draw will be extremely little. During the test flights, the current draw was so little that the tiny solar powered WSPR tracker remained awake and transmitting well into darkness where most other solar powered WSPR trackers would have already gone to sleep with a depleted battery quickly after sunset. The U3B "slept" for only a couple of hours. Although the power of 10mW might look very little, with the wire antenna of a WSPR balloon hanging in free air at about 10 km height it's sufficient to be picked up by the worldwide network of WSPR monitoring stations.

Eventually the U3B will be taken in production and will be sold through QRP Labs. Contrary to most other QRP Labs products, the U3B will not be sold as kit but as an already finished product, as the SMD components will be impossible to work on for the average kit builder. In Friedrichshafen Hans told me he was aiming at having the U3B ready for production in about three months. I think however that the popularity of the new QRP Labs QCX 5W CW transceiver kit might have slowed things down on the U3B development side, although test flights are still being launched; the U3B-9 is over the Atlantic Ocean as we speak.

I'm really looking forward to the U3B being taken in production and to experimenting with the tiny WSPR transmitter myself. My goal eventually is to launch a WSPR balloon myself, but I still have a lot to learn, about solar cells, insulated casings, helium, balloon pressure, the ideal launching weather, wind conditions, trajectory predictions, and probably many more things still unforeseen at this moment. It will be an interesting, but relatively long-haul project. Stay tuned!

Meanwhile my 200mW U3S is still going strong, and since it started sending WSPR beacons for the first time in February, its signals have been picked up all over the world. Some places I want to mention are Reunion, Australia, Brazil and Vladivostok on 20m, and South Africa on 40m, all with an EFHW wire antenna. Do a search on U3S for more of my blog posts on this wonderful little transmitter.


September 22, 2017

5T5OK Mauritania - How Third World power blackouts can benefit the Little Pistol DXer

Last edited:

Most of us in the "Western World" have gotten used to reliable electric power delivery every minute of the day. Not seldomly it's a different situation in many of the poor countries of the "Third World". It's not uncommon for DXpeditions to African countries for instance to be plagued by frequent power outages or power blackouts. It's recently that I've learned that such a blackout can benefit the Little Pistol DXer like me.

5T5OK DXpedition logo
On September 18th, I was trying to QSO the 5T5OK DXpedition in Mauritania in CW on 17m, but I just couldn't get through the pile-up. I was especially keen on making the contact as it would be an ATNO* for me. I'd been fighting the pile-up for quite some time already when, much to my dismay, suddenly the signal of 5T5OK disappeared.
"Power off" reported OK6DJ (one of the 5T5OK operators) on the DX Cluster. I decided to patiently wait on the same 17m band frequency, and then suddenly after about 15 minutes they were back: ".....5T5OK   BLACK OUT HI   QRZ 5T5OK UP"! I quickly started keying my call again, and this time I was the second station to be picked out! Contact made!
Apparently not everybody had managed to bring up the patience I did, and the pile-up must have had decimated considerably, giving me the chance to finally get through to the desert of Mauritania!

Smartphone screenshot of the DX Cluster notification
5T5OK is a Czech DXpedition oparating from Mauritania between September 15-29, 2017. Their QTH is Terjit Vacances Hotel and Grill located at the intersection of the great Mauritanian desert and the Atlantic Ocean near the capital Nouakchott. On the website of Terjit Vacances you can read how, before the road between Nouadhibou and Nouakchott was built, Terjit Vacances was traditionally the point where so called "overlanders" (people travelling in Africa in vehicles over land) would cross the sand dunes into Nouakchott. Before the construction of the road, overlanders used to drive the coastline during ocean low tide to traverse the long distance from Nouadhibou to Nouakchott. During high tide the overlanders had to stop their travels, as the ocean would temporarily eat up the "road".

Mauritania has a population of approximately 4.3 million, and it's estimated that about one-third is living in the capital. 90 percent of the country (the 11th in size in Africa) is within the Sahara.

In the log!
5T5OK uses 100 Watts only, as a power amplifier is not allowed.

Below some photos of the 5T5OK QTH and antennas. All photos from the Czech DXpediton (CDXP) Facebook page.

Below you can listen to the black out message and my contact with 5T5OK. Don't pay attention to the background noises, hi.

* Also read my blog entry ATNO explained


September 15, 2017

From Pole to Pole with the Poles

Last edited: 16.09.2017

Yesterday, I posted a blog entry about the Polish Antarctic Station Henryk Arctowski. But the Poles do not only have a research station in the Antarctic, but also in the Arctic, at Hornsund on the island of Spitsbergen in the Svalbard Archipelago, to be precise.

Polish Polar Station Hornsund (source)
Polish Polar Station Hornsund is located at 77º00'N 15º33'W, and especially during winter is extremely isolated. The station is manned year-round. It was established in 1957 as a winter base for the 3rd International Geophysical Year 1957/1958 (1). There's a permanent staff of about 10 persons. The station is frequently visited by polar bears.


Last April, on the 20m band I managed to make a PSK31 QSO with Kamil Palkowski SQ8KFH who at the time was operating from the Polish Polar Station on Spitsbergen with the callsign JW/SQ8KFH. I'm awaiting a QSL card confirmation via the QSL bureau, and I will post it on here as soon as I've received it.

Spitsbergen is IOTA EU-026.

Polar bear trying to get into the Polish Polar Station (source)

Addendum 16.09.2017
(1) Actually this was the first International Geophysical Year (IGY), but there had been two "International Polar Years" before, on which the IGY was largely modeled.



September 14, 2017

Polish Antarctic Station Arctowski

Last edited:

Beautiful picture from the HF0ARC qrz.com page.
In the evening of September 9th, 2017, I managed to make a JT65 QSO on 40m with HF0ARC. Amateur radio station HF0ARC is located at the Polish Antarctic Station Henryk Arctowski on King George Island, South Shetland Islands, Antarctica. It is operated by Sebastian Gleich SQ1SGB who is part of the current overwintering crew of the 41st Polish Antarctic Expedition (2016/2017) to Arctowski. Austral winter is coming to an end though, and at the end of October, Sebastian will be leaving the station and head back home for Poland. So I feel very lucky to have already managed to put HF0ARC in the log, as time will be running out soon.

I was running my Yaesu FT991 at 35 Watts and used my sloper HyEndFed 10/20/40 wire antenna. I was surprised when I managed to make the contact already on the first attempt! An eQSL for the contact followed the next day. This contact definitely is one of the most special and memorable moments of my ham radio career!

Location of King George Island in the South Shetland Islands (source)
HF0ARC replaces the old Arctowski callsign HF0POL. The old HF0POL call was associated with Arctowski Station up until March 2016, and had been in use at the station since the late 1970s. In 2015, the Polish licensing regulations changed, making it possible to have the HF0 prefix issued to any Polish ham operating from Poland as well. Previously, the HF0 prefix was assigned exclusively to Polish hams operating from the South Shetland Islands. HF0POL is now in use by ham SP9GMK for ham operations from Poland, and is not associated with Arctowski Station anymore.

Polish Antarctic Station Henryk Arctowski was established in February 1977. On the beaches near the station numerous whale bones can be found, remains from the time when the site was used by whalers to process whales killed nearby. Nearby the station are various colonies of three different types of penguins. The station is named for Henryk Arctowski (1871-1958) who as a meteorologist accompanied the 1897-1899 "Belgica" expedition, the first expedition to overwinter in Antarctica. According to Wikipedia, Arctowski proposed the original notion of a wind chill factor, arguing that wind could be as damaging to human flesh as cold in harsh climates.

The South Shetland Islands are IOTA AN-010.

Arctowski Station (source)
Penguins n front of Arctowski Station (source)
Whale bones at Arctowski. Photographer T. Janecki (source)
Winter at Arctowski. Photographer T. Janecki (source)
Arctowski Station. Photographer T. Janecki (source)
eQSL to PA7MDJ from HF0ARC


September 10, 2017

Schynige Platte

Last edited: 13.09.2017

View from Schynige Platte (photo by PA7MDJ)
This summer, I was up at the Schynige Platte in the Berner Oberland region of Switzerland. We took the mountain cog-railway up from Wilderswil to the nostalgic Schynige Platte alpine railway station at 1967 m a.s.l. The view from the Schynige Platte is breathtaking, with the famous majestic, 4 km high trio Eiger, Mönch and Jungfrau towering in the distance. But especially to the SOTA chaser / activator there's also another attraction drawing the attention; the Gumihorn. With 2099 m a.s.l., the Gumihorn is the highest peak of the Schynige Platte. It's also SOTA summit HB/BE-134. But the peak is difficult to climb and is only for the experienced mountaineer. In the past there have been some SOTA activations, but most were invalid, as it turned out afterwards that the activators might have operated close to the actual SOTA activation zone (a maximum of 25 m vertical from the actual summit), but not from within, the zone being not so easy to reach without some serious belayed climbing.

The Schynige Platte railway station (photo by PA7MDJ)
Some SOTA activations are just more epic than others. And one of the more epic ones definitely was the activation of the Gumihorn HB/BE-134 on September 8th, 2017 by Manuel HB9DQM, Matt HB9FVF, and Clemens HB9EWO. Unfortunately I was at work and had to miss the activation, but still I really felt the urge to do this blog entry about it.

The Gumihorn SOTA HB/BE-134 (source)
The three OM took up the challenge to ascend the extremely steep southeastern grass slope, and to climb the last 25 metres of vertical rock face to get to the actual summit of the Gumihorn. And with succes; signing HB9SOTA, they did a valid activation from the summit, and despite bad HF propagation conditions made a total of 56 QSO's (including 11 on VHF).

Matt HB9FVF leading the way to the Gumihorn summit (source)
There's one other activation remaining in the SOTA database, dating back to 2010, done from the peak's southern grass flank, but height measurements taken by the September 8 SOTA climbing party show this may well have been a couple of metres short to be within the SOTA activation zone. It seems the only way to do a valid activation of the Gumihorn is to climb the vertical rock face to the top.

The SOTA climbing party at the summit found a cairn with a summit book from 1970. The book only has a few entries per year, and only one in 2016, and one in 2017, again showing that the Gumihorn is not an easy climb and is rarely visited.

The summit book (source)
Congratulations to HB9DQM, HB9FVF, and HB9EWO for the excellent achievement, both in SOTA and mountaineering!

Succesful activation from the summit by HB9SOTA on September 8th, 2017
The full activation report can be found here on the SOTA Reflector.

Addendum 13.09.2017
A nice slide show / video of the September 8 activation, can be found here on YouTube

The last remaining activation of the Gumihorn, the one of 2010, recently has also been withdrawn from the SOTA database by the activator, as the new height measurements have shown that it most probably was done from outside the SOTA activation zone.

September 09, 2017

First WSPR report from Australia

Last edited:

Finally my 200 mW WSPR signals managed to reach Australia! VK2XN spotted me on the 20m band on August 30th at 1724 UTC.
I used my QRP Labs U3S transmitter and a sloper HyEndFed 10/20/40 wire antenna.

On September 4th, I again was spotted by VK2XN, for a total of 18 times. Best SNR was -21 dB.

VK2XN is located in Bullawa Creek at the edge of Mount Kaputar National Park. Distance to my QTH is 16309 km.

Mount Kaputar National Park (source)
Sawn Rocks, Mount Kaputar NP (source)

August 18, 2017

HAARP and Arecibo ionospheric HF heating research facilities

Last edited:

I've always been highly fascinated by the HAARP facility in Gakona, Alaska. I already was back in the 1990s, when the research station was still operated by the US military and I was still an SWL.
HAARP stands for High Frequency Active Auroral Research Program. At the facility ionospheric research is done. The most prominent instrument at HAARP is the so called "ionospheric heater", a high power HF radio transmitter and antenna array which is used to temporarily excite a limited area of the ionosphere. Wikipedia states that the HAARP facility is capable of transmitting with a power of up to 4 GW ERP.
In 2014, the US Air Force announced that, starting that same year, the HAARP facility would be completely shut down and dismantled. In 2015 however, the control of the facility and all its equipment was taken over by University of Alaska Fairbanks and continues to operate. In February 2017, the first UAF-led research campaign was done. The UAF is not new to HAARP, as they already participated in the program when it was still operated by the military.

Assistant Research Professor Chris Fallen KL3WX of the University of Alaska Fairbanks Geophysical Institute, nowadays is one of the researchers doing ionospheric experiments at the facility, and keeps us posted on the ones that might be of interest to radio amateurs and shortwave listeners. The last research campaign of interest done at the facilty was in February 2017, and the next one will be in September 2017. During the February campaign, the signals of HAARP were picked up by radio amateurs all over the world. For more information, follow @ctfallen on Twitter, or visit his blog at https://sites.google.com/alaska.edu/gakonahaarpoon/.

The HAARP site from the beginning has always been subject to conspiracy theories. Read some more about it at www.haarp.net.

Another ionospheric HF heater recently was constructed at the famous Arecibo Radio Telescope in Puerto Rico. The heater at Arecibo has a nominal power of 600 kW, 100 to 200 MW ERP.
The first research campaign was done this summer, and the signals were received by radio amateurs worldwide, including at PA7MDJ in the Netherlands. A short video compilation of the Arecibo listening sessions done at PA7MDJ, including audio recordings of the signals received, can be found here:

Some more technical info about the Arecibo ionospheric heater can be found here.

Here are some more pictures of the HAARP facility:

HAARP QSL cards!