Tag Archives: DXpedition

Giuseppe’s Ponza Island DXpedition with the Icom IC-705

Many thanks to SWLing Post contributor, Giuseppe Morlè (IZ0GZW), who shares the following guest post:

Report from Ponza Island: May 6-9, 2022

by Giuseppe Morlè (IZ0GZW)

Ciao Thomas and Friends at the SWLing Post!

This is the summary of 3 days of testing of my Icom IC-705 just purchased and immediately taken to Ponza Island, my hometown, for a full immersion DXpedition only listening to amateur radio bands especially on 20 m.

Day 1

I left Formia on the ship that went to Ponza and it was not a good start given the adverse sea weather conditions. After 3 hours of crossing in the rain and the strong sirocco wind, I arrived on the island at my father’s house.

In the early afternoon in the rain, I hoisted a 20 meter row on the “sloper” type roof not so high from the ground and connected directly to the Icom 705 without any counterweight given the place without electrical noise.

The position of my father’s house is open from West to North but totally covered to the South by a hill of 200 meters …

In this video you can see all of this:

During the first night, 20 meters was full of signals especially from the USA; it was, in fact, what I had hoped for given the position open to the West.

Really good overseas signals despite bad weather … below is a series of mixes of North American stations: Continue reading →

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Guest Post: Don targets rare Norwegian stations during Newfoundland DXpedition

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Photo by the Bjørnøya Meteorologiske Stasjon

Many thanks to SWLing Post contributor, Don Moore–author of Following Ghosts in Northern Peru–for the following guest post:

The Rarest DX?

By Don Moore

In mid-October I received an invitation to attend the annual DXpedition in Cappahayden, Newfoundland with Jean Burnell, John Fisher, and Jim Renfrews. It didn’t take long for me to say yes. Newfoundland is one of the best places in the world to DX from and all kinds of amazing stuff has been heard there. I was excited at the prospect of great medium wave DX and being able to log low-powered European private and pirate shortwave broadcasters.

But something else was at the top of my try-for list. One of my many DX interests has always been logging coastal marine stations in the 1600 to 3000 kHz range. In preparation I started checking online sources to update my spreadsheet of schedules. In going through a recently added section on Marine Broadcasts in the DX Info Centre website I came across listings for twice-daily weather broadcasts from Hopen Island on 1750 kHz and Bjørnøya (Bear Island) on 1757 kHz.

I didn’t remember ever seeing anything about broadcasts from these remote islands in the Norwegian Arctic before. Were these stations actually on the air, I wondered. And if they were, could I hear them in Newfoundland? Continue reading →

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A Compact RSPdx & Wellbrook Loop Kit for the Beach — My Approach

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I have enjoyed three to four medium wave and shortwave DXpeditions per year since 1988, to sites on the Washington and Oregon coasts. I love the chance they give to experiment with antennas in a (hopefully!) noise-free location, and concentrate on catching stations that might not be heard from home.

All of my DX trips have been via car–until now! I’ve just returned from nine vacation days in Hawaii (Waikoloa Beach, on the Big Island), and I thought others might like to see the radio related items I chose to take along for air travel. I’m pleased to report that everything worked as planned, and I have five days of SDR IQ WAV files of the MW band for review, all recorded in the time frame surrounding local dawn.

My goal was not the smallest, most compact portable setup, but one with high performance and modest size. Fitting everything into a day pack was another requirement. A simple wire antenna and an even smaller Windows tablet or laptop than the one I’ve used (and a smaller SDR like the HF+ Discovery, for that matter) would make a much smaller package. However, the items I’ve assembled worked excellently for me during my enjoyable Hawaii vacation. The directional loop antenna provided nulls on medium wave of 30 dB during preliminary tests indoors, a less-than-ideal test situation.

Waikoloa Beach–just one of a zillion picturesque scenes in Hawaii.

Here is a list of what I’ve put together for my DXing “kit”:

- SDRPlay RSPdx receiver
- Short USB cable for receiver<>PC connection, with two RFI chokes installed
- Lenovo X1 tablet— a Windows 10 device with magnetically attached keyboard; this model is a competitor to Microsoft’s Surface Pro tablet
- Wellbrook Communications’ ALA1530 head amp module, modified for female SO239 connectors enabling use of large diameter LMR-600 coaxial cable as a 2-turn loop element. My antenna setup is similar to Wellbrook’s commercial flexible loop
- Wooden base for the antenna (ALA1530 is bolted to the base)
- 20 feet of lightweight RG-174 coax
- Wellbrook DC interface module for the ALA1530
- 3.0 Ah LiFePO4 rechargeable battery for the Wellbrook antenna
- 15 foot long section of high grade “Times Mfg.” LMR-600 coax cable with PL259 connectors (bought from Ebay already assembled/soldered)
- Fold-up beach mat
- Small day pack to hold everything

All the contents of this DXing setup fit a standard size day pack.

You’ll note the absence of headphones in the list. This is because my intent from the start was to record all the DX (MW band) as SDR WAV files for DXing post-vacation. That said, I did have headphones in my travel luggage for later spot checks of a few frequencies. That’s how I found 576 kHz Yangon, Myanmar lurking at their 1700 sign-off with national anthem and English announcement. The remainder of the DX to be uncovered will have to wait until I’m back home near Seattle!

The LMR-600 is a very thick and stiff coax cable, whose diameter approaches that used in the standard aluminum tubing ALA1530 series from Wellbrook. It has the benefit of being self-supporting in a 2-turn configuration and will also coil up into an approx. 12-inch package for transport. It just barely fits within the day pack I’m using. As I understand it, magnetic loops with tubing or large coax as the active element, versus simple wire, are more efficient in operation. Whether or not this holds true in practice remains to be seen.

I fashioned a wooden disc 3/4″ thick to attach the ALA1530 head amplifier, as I didn’t want to bring along a tripod or other support stand. The Wellbrook antennas all work well near or at ground level, so I was able to get great reception with the antenna right on the beach. The diameter at two turns of the coax is only a few inches smaller diameter than Wellbrook’s aluminum tubing loops. Three strips of strategically placed Velcro straps help keep the turns together when deployed as well as during storage.

In theory a two-turn loop should give 5 dB less gain than a single turn version; however, my older ALA1530 module has 5 dB more gain than the newer “LN” type, according to Andrew Ikin of Wellbrook Communications. The net result is that my two-turn antenna should have equal gain to the larger one-turn variety. Future experimentation with this DIY coax loop antenna is in order!

The Wellbrook loop antenna, RSPdx receiver, and Windows 10 tablet on the beach in Waikoloa, Hawaii.

Another view of the DXing position. Being this close to the water with my radio gear was unnerving at first, but the wave action on a calm Hawaii beach is totally different from the Oregon/Washington beaches with waves that can move in and out by a hundred feet or more.

The Wellbrook “DIY FlexLoop” works fine at beach level, and is less conspicuous this way, too.

The ALA1530 module is bolted to the 11-inch wooden disc for support. I’ve modified the module’s sockets to securely hold SO239 female connectors.

The commercial Wellbrook FLX1530LN is a fine product, and worthy of your consideration as a compact and high performance travel antenna. Full details can be found at this link.

SDR WAV Files for Download

One of my goals from the start for my Hawaii trip was to bring back SDR “IQ” WAV files for sharing with others. These approx. 900 Mb files cover the entire medium wave band as heard from my beach location in Waikoloa.

The overall page is: https://archive.org/details/@4nradio Clicking on any of the entries will bring you to a details page. From there just right click on the “WAVE” link, and choose “Save as…” to download. For a few of the recordings I also posted the file that precedes the one that goes across the top-of-the-hour, because things seemed a bit more lively prior to 1700 (which was at local sunrise, give or take a couple of minutes).

The IQ WAV files are only playable with suitable SDR radio software: SDRuno is first choice (but you need a RSP receiver connected). The files are also is compatible with HDSDR and SDR-Console V3. It may also play on Studio 1 software.

I hope other DXers enjoy the chance to tune through the MW band, as heard from the Big Island of Hawaii.

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington. He’s a regular contributor to the SWLing Post.

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Guest Post: Radiofreunde NRW’s DXpedition-grade signal distribution system

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Many thanks to SWLing Post contributor, Joachim von Geisau (DH4JG), for the following guest post:

Signal distribution at SWL camps: The new JK-1000 HF distributor

by Joachim von Geisau (DH4JG)

The Friends of Radio NRW – an independent group of shortwave listeners and radio amateurs in Germany – have been organizing 2-3 SWL camps per year for a number of years, where they meet as far away as possible from electrical noise in order to listen to shortwave together.

To distribute antenna signals, we have previously used an RFT AVV01 antenna distributor.

At an SWL camp there are high demands on signal distribution. Both very weak and strong signals should be distributed well, un-distorted, without noise and other interference. The signal levels are approximately between 0.2 ?V (S1) to over 5 mV (S9 + 40 dB), with a frequency range of at least from 150 kHz to 30 MHz, thus broadcast bands from LW to SW are covered, also all amateur radio bands from 160 m to 10 m.

Popular among listeners are RFT AVV01 RF distributors from the former GDR, at least 30 years old. However, the use of an AVV01 has several disadvantages: high power consumption, difficulties in getting spare parts, high upkeep with corroded contacts and the like. In addition, the transmission of the LW/MW range drops, which is a disadvantage especially for MW listeners. The NV-14 system from Rohde & Schwarz from the late 1960s has the same weaknesses.

Two years ago, the desire arose to develop a concept for the replacement of the RFT system.
The following aspects were important:

Frequency range at least 100 kHz – 30 MHz, as linear as possible
frequencies below or above desirable
Running on 12 V DC or integrated noise-free power supply
Remote power supply for active antennas
Robust structure
Versatility
Hobby friendly budget

The amateur radio market offers several products for RF signal distribution (e.g., ELAD, Bonito et al.), but no solution to distribute 6-8 antennas to 10-12 receivers. It was clear from the beginning that DIY development was inevitable.

The starting point of the considerations was to integrate remote power supply for active antennas, an amplifier stage and a distribution network.

Such a distributor is able to distribute an antenna signal to several receivers; several antennas require several such distributors, which led to the decision to implement the project in plug-in technology.

With OM Frank Wornast DD3ZE (www.dd3ze.de), known e.g. for his converters, filters and the like, a well-known RF developer could be won, who took over the implementation of the concept based on the detailed specifications. OM Wornast first produced a prototype without remote power supply, which already did an excellent job of RF signal distribution.

A “hardness test” at an SWL camp showed that this distribution module easily fulfilled our requirements: Frequency range 10 kHz – 50 MHz (also usable with a few dB loss above 50 MHz). Supplemented by a switchable remote power supply and a 90V gas discharger at the antenna socket, the final PCB layout was created, representing the core of the new HF distribution system of Radio Freunde NRW

The distribution block consists of the following components:

Input with 90V arrester & 100 kOhm MOX resistor to dissipate static interference
Remote power supply, switchable, 10-14 V, max. 350 mA
Amplifier stage with 14-14.5 dB
Resistor network for distribution

The device is characterized by a very smooth frequency response and has a very low inherent noise. It offers the possibility of using levels of -120dBm with very good SNR
to process up to strong levels of up to + 14dBm. In addition, the reception on VLF is now possible, which did not work with the previous system.

The PCB is designed in a very practical way: series resistors for LEDs are integrated as well as fixing points for coaxial cables. The remote power supply can be switched separately, but can also be used permanently by means of a jumper.

With this concept, the distribution block can be used universally: use on an active or passive antenna with distribution to several receivers, by means of a step switch in front of it also for several antennas; if you leave the remote feed path unconnected, the block can also be used as a simple distributor, so it is almost universal for hobby purposes.

For use on SWL camps, we decided to install them in 19 “rack-mount technology. A standard rack can thus accommodate 4 distributors and a power supply, allowing distribution of 4 antennas to 12 outputs each. An example of the installation is shown in the following picture: Parallel to the input is another BNC socket, which is connected via a C 100 nF where the input signal can be used DC-free for measurement purposes or the like. The distribution unit is installed in a transport case. The components themselves are mounted in slide-in housings which are provided with a corresponding front panel: Such front panels might be obtained from CNC manufacturers.

On the back + 12V DC must be supplied as operating voltage. For the power supply units, we opted for linear power supplies because we have made the best experience with these without interference. For a distribution unit with 4 slots, a power supply with 12V 1A is sufficient – each distribution block takes about 55 mA, an active antenna up to 150 mA, so even with “full load” a power supply with 1 A is sufficient. The distributor was tested with various well-known active and passive antennas, including a PA0RDT MiniWhip, active loops, long wires and T2FD.

Due to the wide input voltage range, the module can handle nearly any antenna. The cost for a distributor for 4 antennas amounts (depending on the version: housing, sockets, switches, power supply, etc.) to about 700-1000 €. That may seem a lot at first glance. However, taking into account that a simple 5-gang distributor from mass production costs already around 250 ¬, the cost of the distribution of 4 antennas to each up to 12 outputs are not that much. The Friends of Radio NRW use two of these distribution units for SWL camps.

If you are interested in building one, please contact the author ([email protected]) for further information. The development history of the distribution unit is also available at www.dx-unlimited.eu.

Wow! What a beautifully engineered antenna distribution solution, Joachim! I love how you worked together to sort out all of the requirements for your system then build it for ultimate performance and flexibility. No doubt, you and your colleagues at Radiofreunde NRW posses a lot of design and engineering skills! Simply amazing and thank you for sharing your design with the radio community!

Contact Joachim for more details and check out notes and discussion at www.dx-unlimited.eu (may require registration).

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Videos from DXcamp Marajó Island, November 2019

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Photo: Ivan Dias & Martin Butera, during the first Dx-Camp 15.61 Crew Radio Listeners’ Marajó Island – Amazon Rainforest, North of Brazil – November 2019

Many thanks to SWLing Post contributor Martin Butera, founding member of the 15.61 Crew, for the following guest post:

The 15.61 Crew Radio Listeners, Martin Butera and Ivan Dias, give us a small video preview made in the first Dx-Camp on Marajó Island in the Amazon Rainforest, North of Brazil on November 2019.

There are more than 11 hours of SDR recordings and videos of the Ultralight radios, which will take much additional time to process, of course.

Crew is working on the report with a complete story that includes videos and photos of everything experienced during the DX-Camp–this will be published in several languages and the first LOG, which we estimate will be the first months of the South American summer 2020.

We recommend not forgetting to periodically visit the official site of the DX-Camp, to find updated information: https://dxcamp-marajo2019.blogspot.com/

Above, you’ll see a short stretch of the medium wave band with plenty of interesting content: 585 kHz, alternating between National Radio of Spain (Madrid), BSKSA (Saudi Arabia), 590 kHz, alternating with Poty Radio (Crateús / CE), Radio Diffuser (Boa Vista / RR) and Radio Continental (Buenos Aires), 594 kHz BSKSA (Saudi Arabia), 595.9 kHz SNRT (Morocco – operating off-frequency for years), 600 kHz Mirante Radio (São Luís / MA), Vale Radio (Barreiras) / BA) and Radio Gaucha (Porto Alegre / RS) and 603 kHz National Radio of Spain (Sevilla).

Videos

All of the following videos were captured during the November 2019 Dx-Camp:

Brazil is a country with vast continental distances. The following three videos showcase Brazilian radio from across the country.

Radio Diffuser Boa Vista (1408 km distance)

Radio Itatiaia 2191 (km distance)

Radio Band B (2747 km distance)

Photo: Ivan Dias & Martin Butera, during the first Dx-Camp 15.61 Crew Radio Listeners’ Marajó Island – Amazon Rainforest, North of Brazil – November 2019

More photos of the DX-Camp from the official site:

https://dxcamp-marajo2019.blogspot.com/p/photos.html

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Mark’s Tree House DXpedition in Bali

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I recently received an email from SWLing Post friend, contributor and Patron, Mark Fahey, who is currently enjoying a fascinating DXpedition.

Many thanks to Mark who has allowed me to share a few of his notes from the trip. Mark writes:

I am at Susut, in the Bangli Regency, on the Indonesian island of Bali.

This treehouse is at the base region of Mt Agung, an active volcano, so the earth rumbles a few time each day.

For the next week and a half, I am alone in the Indonesian jungle with my WinRadio Excalibur a collection of loops and wire antennas and lots of storage for spectrum recording. No QRM, I am running on DC, but charge my gear during the day from an AC mains supply.

DX is fantastic – best today being CNR in DRM locked solid!

But the big disappointment is just like Malaysia, MW in most of Indonesia is now just white noise, nothing at all – and hardly any RRI (Radio Republik Indonesia) on the tropical bands now.

But FM jam-packed, I expect many are community pirate stations as well. I came all setup for FM capture as well.

Wow! What a brilliant DXpedition location, Mark! It appears you’ve truly removed all other distractions being in such a remote area.

Sign me up! I’m ready for some Indonesian tree house DXing!

Thanks for sharing, Mark! [And by the way, I’m not at all envious. Okay, maybe just a little. Or a lot.]

Post readers: Have you ever been on a DXpedition in an exotic or unique location? Please comment!

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Results: AirSpy HF+ vs Elad FDM-S2 Weak Signal Comparisions

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Looking north toward Cape Lookout, Oregon, near the site of my SDR receiver recordings. Photo courtesy of Wikimedia Commons.
In my original article 10 days ago, I set up a SWLing Post reader poll to let you give your opinion on which shortwave recordings within four pairs of audio files provided the most intelligible result. The recordings were intentionally noisy, low-level signals to help us discover–through critical listening to the files–if there is a clear favorite between the AirSpy HF+ or the Elad FDM-S2 receivers. Of course, there were only four pairs of recordings…not a very large sample size.

However, 34 readers of the original article took the time to listen and respond, so let’s get to the numbers, shown in these graphs:

Interestingly, the responses above seem to point to:

Two recording pairs tied in the results (50% / 50%) or were very close (HF+ 52.9% / FDM-S2 47.1%)
The FDM-S2 led one recording pair by a large margin (67.6% / 32.4%)
The HF+ led another recording pair by an equally large margin (67.6% / 32.4%)

Taken as a whole, no obvious winner emerged, although one might conclude the HF+ has a slight edge due to its lead in the “very close” recording pair of 7.230 MHz.

One thing is clear–the AirSpy HF+ is a surprisingly good performer for its price of $199 USD! For many enthusiasts this will be all the SDR they need.

As a final note, I’ll mention that the AirSpy HF+ used for the tests was totally stock. I have not yet performed the “R3 Bypass” mod nor the firmware update to my HF+ units. The simple R3 Bypass, discussed at length on the AirSpy Groups.io forum, significantly boosts sensitivity of the HF+ from longwave up to about 15 MHz, without any noted overload issues. For more on this modification from a MW DXer’s perspective, read Bjarne Mjelde’s insightful article at his Arctic DX Blog.

Thank you to all the readers who took the time to listen to the SDR recordings in this comparision and register your opinions.

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington. He’s a regular contributor to the SWLing Post.

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