Category Archives: Ham Radio

Teaching an old dog old tricks

By Jock Elliott, KB2GOM

It was Don Moore’s excellent article — An Introduction to DXing the MF Marine Bands — that inspired me. If you haven’t read it, do so now; it’s terrific. But be warned: my guess is that it will inspire you too.

Bottom line, ever since I read it, I have very much wanted to hear at least some of those MF marine stations that Don writes about. One of Don’s recommendations is “Hang Out on 2182 kHz.” So sometimes when I am messing around in the radio shack, I will park one of my shortwave receivers on 2182 USB in the hopes of hearing some marine communications. 2182 is the frequency that the US Coast Guard once monitored as a distress frequency, but no more.

According to Don: “Today 2182 kHz still gets some use as a calling frequency, where a ship and a shore station quickly arrange to have a conversation on another frequency. But the more common use now is for shore-based marine broadcasters to pre-announce marine information broadcasts they are about to transmit on other frequencies.”

Just the other day, I brought up 2182 on my Satellit 800, but the atmospheric noise was pretty bad. I fooled around with a couple of different indoor wire antenna configurations but wasn’t able to achieve any substantial improvement. But in the midst of that messing around, I “rediscovered” my Icom IC-706 MkIIG on a shelf. It receives from 30 kHz to 199 MHz and from 400 to 470 MHz, and I used mine for over a decade to run the Commuter Assistance Network on two meters. I still keep the 706 as a back-up in case my main rig for running the net goes down.

But I had never used the 706 extensively on HF (weird, I know, but that’s the truth). Nevertheless, a little voice in the back of my head (probably one of the brain dudes) kept saying “Why don’t you give the 706 a try as an HF receiver?”

So I did. I hooked up the 706 up to my horizontal room loop through some coax and an LDG 9:1 unun (the same antenna setup I had been using on the Satellit 800). And – shazam – the 706 is substantially quieter on 2182 with that antenna than the Satellit 800.

That’s good, I thought, but what if the 706 appears to be quieter because it is less sensitive? So I did some comparative tests with the 706 and the Satellit 800 on the 80 and 40 meter ham bands and satisfied myself that the 706 is both quieter and more sensitive than the Satellit 800. I could just plain hear the signals better (and more pleasantly) with the 706.

The only substantial weirdness with the Icom 706 MkIIG is that, as a small unit, it has relatively few buttons on its face. As a result, it has no keypad for direct frequency access. There are buttons for jumping from one ham band to another and another button for changing tuning steps, so with judicious use of those buttons and the tuning knob, it’s fairly easy to get from one frequency to another, but it is not as fast as direct entry.

And, of course, the 706 does not have all the cool seek-and-store functions and the like that are available on today’s really slick shortwave portables.

Here’s the upshot: if you’ve been on the hunt for a better HF receiver with single sideband capabilities, an old dog, like an old ham transceiver, might be just what you need. And if you are already enjoying an old ham transceiver as a shortwave receiver, I’d like to hear about it.

So, have I heard any of those cool MW maritime stations? Not yet, but I’m sure I’ll have fun trying!

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Radio Waves: Maverick-603 SDR for FT8, EC-130J Commando Solo Final Broadcast, WRTH Survey, and Railways On The Air

EC-130J Photo By Staff Sgt. Tony Harp | An EC-130J Commando Solo aircraft from the 193rd Special Operations Wing performs a flyover during Community Days at the Lancaster Airport in Lititz, Pennsylvania, Sept.17, 2022. (Source: DVIDS)

Radio Waves:  Stories Making Waves in the World of Radio

Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!


RadioStack’s Maverick-603 Is a Fully-Functional Open-Silicon Software-Defined Radio for FT8 (Hackster.io)

Built using open tools and readied for manufacturing at SkyWater using the Efabless platform, the chip on this SDR is something special.

New Hampshire-based RadioStack is looking to launch a piece of amateur radio equipment with a difference: the Maverick-603 is powered by free and open source silicon, built using the Efabless platform at a SkyWater fab.

“Maverick-603 is the first affordable FT8 receiver board built around an RF receiver chip that was designed using fully open source tools and fabrication,” its creators explain. “It is capable of acquiring FT8 signals between 7MHz and 70MHz. With this frequency range, you will be able to receive signals from around the world with high accuracy. The use of our Low Noise Amplifier (LNA) will also give the chip the ability to amplify very low-strength signals, which is necessary for an effective FT8 receiver.” [Continue reading…]

EC-130J Commando Solo performs final broadcast (DVIDS)

MIDDLETOWN, PA, UNITED STATES
09.17.2022
Story by Master Sgt. Alexander Farver
193rd Special Operations Wing

Airmen from the 193rd Special Operations Wing here, who operate the only flying military radio and TV broadcast platform in the U.S. military, transmitted their final broadcast today to spectators at the Community Days Air Show at Lancaster Airport, Lititz, Pa., bringing to close a 54-year chapter in unit history.

The EC-130J Commando Solo mission has helped keep this Air National Guard unit’s aircraft and its Airmen at the tip of spear for nearly every major U.S. military operation since the Vietnam War. Before bombs dropped or troops deployed in the Global War on Terror following the attacks on Sept. 11, 2001, this specially modified aircraft was already over the skies of Afghanistan broadcasting to America’s enemies that the U.S. military was bringing the fight to them.

“Any world event or crisis that our military has responded to in recent history, our 193rd Airmen – and Commando Solo – were likely key components in that response,” said Col. Eric McKissick, 193rd SOW vice commander. “As we prepare to open a new chapter in our history, we thank those who have enabled us to be among the very best wings in the Air National Guard.”
The genesis for this airborne information operations platform can be traced back to 1968 when the 193rd Tactical Electronics Warfare Group received its first aircraft, called the EC-121 Coronet Solo. In the late 1970s, the aircraft were replaced by the EC-130E before finally being replaced by the current aircraft in 2003. Throughout its history, it was instrumental in the success of coordinated military information support operations, earning the wing the moniker of “the most deployed unit in the Air National Guard.”

These deployments included: Operation Enduring Freedom, Operation Iraqi Freedom, Operations Odyssey Dawn/Unified Protector in Libya, Operation Inherent Resolve, Operation Resolute Support/Freedom’s Sentinel, Operation Secure Tomorrow and Operation Unified Response in Haiti.

Although this unique mission has earned the wing many prestigious accolades, Lt. Col. Michael Hackman, 193rd Special Operations Squadron commander, believes the mission’s success and legacy lies in winning the hearts and minds of adversaries and providing vital information to allies, refugees and victims in times of crisis.

“This capability has been an essential tool in our nation’s inventory, from the battlefields to assisting hurricane and earthquake-ravaged nations,” Hackman said. “During this time, thousands of Pennsylvania Air National Guard volunteers fulfilled their call to duty in this unique capacity, leveraging this capability against U.S. adversaries and supporting allies while always fulfilling the unit tenet of ‘Never Seen, Always Heard.’”

Aside from sporting an impressive operational record, the aircraft holds another distinction with having completed over 226,000 hours of accident-free flying.

“Having that many thousands of hours of accident-free flying is a testament to the excellence of our maintainers, to the operators and anybody who has touched that aircraft. Thank you for leaving that foundation and setting that example that we’re building from,” said Col. Jaime Ramirez, 193rd Special Operations Maintenance Group commander.

McKissick believes the success of the 193rd in operating the Commando Solo mission over the past few decades has led to Air Force Special Operations Command selecting the wing to be the first and only ANG unit to operate the MC-130J Commando II. The Commando II flies clandestine, or low visibility, single or multiship, low-level infiltration, exfiltration and resupply of special operations forces, by airdrop or airland and air refueling missions for special operations helicopters and tiltrotor aircraft, intruding politically sensitive or hostile territories.
“Today we honor the men and women, past and present, who have served this unit and mission with unparalleled distinction,” said McKissick. “The Airmen who came before us created an enduring culture and spirit of hard work, innovation and grit. We thank them for that, and we will do our best to carry this forward.”

The final broadcast of the EC-130J was transmitted to the ground and played at the Community Days Air Show at Lancaster Airport. In the transmission, the wing thanked the local community for their support over the past 54 years before broadcasting the Santo and Johnny song, “Sleepwalk.” The transmission ended with the phrase, “Commando Solo, music off.” [Read the full article here…]

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Railways On The Air (Southgate ARC)

The South Eastern Amateur Radio Group (EI2WRC) will be active from The Waterford and Suir Valley Railway station Kilmeaden, Co. Waterford for the ‘Railways On The Air‘ event on Sunday, the 25th of September.

WSVR is a community heritage project. The project has enabled the magic of rails golden age to be brought to life in Kilmeaden. A heritage narrow gauge railway runs along 17 kilometres of the abandoned Waterford to Dungarvan line.

The South Eastern Amateur Radio Group would like to thank the manager Maria Kyte and all the staff of The Waterford and Suir Valley Railway for all their help and allowing us access to the station to do this event again this year. For more information about the WSVR please see www.wsvrailway.ie .

The September meeting of the South Eastern Amateur Radio Group EI2WRC will take place on Monday, the 26th of September 2022 at 8.00 p.m. sharp at The Sweep Bar, Adamstown, Kilmeaden, Co. Waterford, Eircode X91 H588. New members or anyone interested in learning more about amateur radio or the group are as always very welcome to attend.

For anyone that wishes to find out more about the South Eastern Amateur Radio Group and their activities you can drop them an email to southeasternarg /at/ gmail.com or please feel free to go along to any of their meetings. You can check their website www.searg.ie and you can also join them on Facebook and follow them on Twitter.


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Radio Waves: BBC Transmitter Audio Feed, New DRM Receivers Showcased, QSO Today Virtual Ham Expo, and New German Class “N” Ham License

Radio Waves:  Stories Making Waves in the World of Radio

Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!


How the BBC (still) sends audio to transmitter sites (Hackaday)

Running a radio station is, on the face of it, a straightforward technical challenge. Build a studio, hook it up to a transmitter, and you’re good to go. But what happens when your station is not a single Rebel Radio-style hilltop installation, but a national chain of transmitter sites fed from a variety of city-based studios? This is the problem facing the BBC with their national UK FM transmitter chain, and since the 1980s it has been fed by a series of NICAM digital data streams. We mentioned back in 2016 how the ageing equipment had been replaced with a modern FPGA-based implementation without any listeners noticing, and now thanks to [Matt Millman], we have a chance to see a teardown of the original 1980s units. The tech is relatively easy to understand from a 2020s perspective, but it still contains a few surprises. [Continue reading at Hackaday…]

Receivers Introduced At Pre-IBC Event To Be Seen At RAI On Sep 10th (DRM Consortium)

This year’s IBC DRM virtual event, held on 6th September, was very well received by many participants world-wide. The much-awaited session on DRM receivers gave the listeners and viewers the opportunity to learn about new, hot off the press, receiver products and solutions in this sector.

A new cost-effective DRM solution developed by CML Microsystems in conjunction with Cambridge Consultants in the UK, is just one example. Their product is a multi-band broadcast DRM receiver module that makes it quick and easy for manufacturers to build DRM radio sets. The module supports DRM and analogue reception in the AM and VHF bands. Applicable IP royalties are included in the module price. The module also supports a remote controlled mode and thus can serve as the basis for full-featured DRM radio sets. The module is scheduled to be available to industry partners from Q1 2023.

Gospell from China presented their entire range of well-established and full-featured DRM receivers consisting of desktop and pocket radios, with support for EWF Emergency Warning Functionality and Journaline text service. In addition, Gospell unveiled their new car radio for easy integration, the Stereo Digital Radio Receiver GR-520. All models provide DRM reception across all DRM broadcast bands.

The Swiss company Starwaves announced three upcoming DRM receiver solutions: A complete and full-featured DRM and analogue AM/FM receiver module available to receiver manufacturers, with automotive-grade tuning and fast scanning across all DRM frequency bands and support for EWF Emergency Warning Functionality and Journaline text service. A first consumer receiver model built on this DRM module will be the W2401 desktop radio priced at €79. An even more advanced receiver at 99€ will in addition feature a built-in WiFi hotspot for web browser access to the DRM content. All Starwaves receivers can be enhanced with DAB+ functionality if required by a local market.

Starwaves also offers the DRM SoftRadio App for Android phones and tablets, which upgrades any device by connecting an analogue RF SDR dongle to a full-featured DRM receiver. The app is available in major app stores including Google, Huawei and Amazon.

Exciting DRM receiver solutions for professional applications and device manufacturers were presented by Fraunhofer IIS (Germany), such as the automotive receiver kit software SDR, and the DRM MultimediaPlayer Radio App as the basis of professional and consumer-grade radio implementations.

NXP, the leading, global semiconductor manufacturer, showcased their complete portfolio of automotive qualified suite of DRM chipsets for car receivers for all DRM broadcast bands.

Other companies from India, such as OptM and Inntot, as well as the South Korean manufacturer RF2Digital contributed to the pre-IBC DRM virtual event with videos presenting their solutions for DRM use in desktop radios, mobile phones and in cars.

CML Microsystems/Cambridge Consultants, Gospell, Starwaves and Fraunhofer IIS will also be present in Amsterdam during the IBC expo on the 10th September together with other key DRM members, such as BBC, Encompass, Nautel and RFmondial. IBC visitors participating in the two DRM sessions at the Fraunhofer IIS booth and at the Nautel booth will experience live demonstrations of the new DRM receivers and modules.

Selected news from the presentation on September 6th including from the DRM receiver section are available as a free download: https://s.drm.org/KJr9.

[Click here to read the full article.]

QSO Today Virtual Ham Expo is this weekend!

[The] QSO Today Virtual Ham Expo kicks off this Friday evening, September 16th at 1800 Pacific.

The Expo officially opens on September 17 2022 at, 01:00 UTC or September 16th at 6:00 PM Pacific.

To attend, all you need to do is go to the following website: https://qsotoday.vfairs.com. Simply login using the same email address that you used to purchase your ticket. No password is needed. You can test in advance to see that it works.

Click here to purchase your ticket and attend!

Germany: New Entry-Level license class ‘N’ on its way (DARC via Southgate ARC)

DARC reports on the planned introduction of an entry-level amateur radio license, it will be limited to just 10w EIRP in the 144 and 430 MHz bands but they can build their own equipment

A translation of the DARC post reads:

Today [June 7], the Federal Ministry for Digital Affairs and Transport presented the draft of a new amateur radio regulation that will bring some innovations for all radio amateurs.

The chairman of the DARC e. V. and the Round Table Amateur Radio (RTA), Christian Entsfellner, DL3MBG was pleased: “The new regulation implements long-standing requirements of the DARC and the Round Table Amateur Radio. Remote operation will finally be allowed in the future. The Ministry has also implemented our demand for a beginner class, which has existed since 2008.

This makes it much easier to get started with amateur radio.” While the existing classes E and A are raised in level due to the introduction of new topics from digital technology, class N focuses on operational knowledge, regulations and basic knowledge of the technology.

Holders of the new Class N will be allowed to transmit on 2m and 70cm with a maximum power of 10W EIRP. “The new entry-level class should offer access to amateur radio in particular to young people and older people in accordance with international requirements,” explains board member Ronny Jerke, DG2RON. The legally stipulated self-build right is not restricted, so even beginners can develop, set up and put into operation radio devices or hotspots themselves.

The exam will follow a cumulative system, e.g. B. is known from the US amateur radio test. First of all, the exam for class N is taken, which already contains all questions from the areas of operational knowledge and regulations. The technical test for class E and then for class A can then be taken.

“The examination catalogs developed by the DARC for the three classes are structured in such a way that the content and questions are not repeated, i. H. Content that has already been examined in a lower class no longer plays a role in the examination for a higher class. So all future radio amateurs go through the exams of class N, through E to class A. It should be possible to take all the exams in one day.

The previously unregulated remote operation has been included in the new amateur radio regulation. Holders of license class A may in future operate amateur radio stations remotely and also allow other radio amateurs to use class A. Another important innovation concerns the training radio operation, which will be possible in the future without a separate training call sign. Instead, adding the prefix “DN/” makes any Class E or Class A callsign a training callsign.

The RTA now has 4 weeks to comment on the draft regulation. The board and the departments of the DARC have already started to examine the text of the ordinance in detail and will report promptly.

The press release from the Federal Ministry for Digital Affairs and Transport can be found at
https://bmdv.bund.de/SharedDocs/DE/Pressemitteilungen/2022/065-kluckert-amateurfunkverordnung.html

Attached to the press release is a draft of the second ordinance amending the amateur radio ordinance. This can be found as a PDF file at

https://bmdv.bund.de/SharedDocs/DE/Gesetze-20/zzwei-verordnung-aenderung-amateurfunkverordnung.html

Source DARC https://darc.de/

 


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Giuseppe Demonstrates his homemade “Minimal Long-Distance Dipole”

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

Dear Thomas and Friends of the SWLing Post,

I’m Giuseppe Morlè from Formia, central Italy on the Tyrrhenian Sea.

This time I want to show you 2 QRP connections made with minimal antenna over long distance and very few watts of power…

The antenna is a simple dipole, 5 meters per arm, 1/4 wave for 20 meters, on a bnc / banana socket directly on the Icom 705. You’ll see that the ROS is really optimal.

I wanted to experience this very simple antenna, easy to prepare in this location surrounded by greenery, Monte Orlando Park in Gaeta on my favorite DX bench;
this location is at 120 meters above sea level and facing south / west following the long path.  A suitable place for the extreme right made especially for a receiver like the Icom 705– fantastic modulation and without any kind of noise.

In the first video the contact with VK2GJC, Greg from Australia who struggles a little to listen to me but immediately understands my name. As you can hear Greg’s voice is without any imperfection even if his signal is not that high:

In the second video, another link with Australia, VK5AVB, Tony from Kangaroo Island.
Tony had a hard time understanding my name but with the help of Nicola, IU5EYV from Tuscany, in pure Ham Spirit, he finally managed to log me:

As you can see, even with very minimal antennas hoisted on nearby trees, not even high from the ground, you can listen and contact over long distances … that’s why I love this place so much!

Thanks to you all, a cordial greeting from Italy.

Many thanks, once again, Giuseppe for showing us just how much fun we can have by building our own antennas and hopping on the air with very little power. I must say: you certainly play radio in a beautiful part of the world! Thank you!

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Treetop Antennas: Featured with my friend Wlodek (US7IGN) on BBC Radio 4 Short Cuts

I’m very honored to be featured with my good friend Wlodek (US7IGN) in a short radio documentary on BBC Radio 4 today.

Wlodek is long-time reader and subscriber here on the SWLing Post and QRPer.com. Wlodek lives in Kiev, Ukraine and we keep in touch these days over email. Like me, he is passionate about field radio work and before the Russian invasion, you’d often find him in nearby forests experimenting with some pretty impressive field antennas.

Sadly, when Russia invaded Ukraine earlier this year, it very quickly brought an end to all of that for Wlod. Not only were amateur radio operators not allowed to transmit under the state of emergency, but it’s no longer safe to venture into nearby forests.

Radio producer, Cicely Fell, learned about our love of all things field radio and put together an audio piece that airs today on BBC Radio 4:

BBC Radio 4 Short Cuts

From the forests of North Carolina, USA to the city of Kyiv, Ukraine – two ham radio enthusiasts seek each other out and a voice from the past prompts a dialogue on listening between a rabbi and a radio producer.

Click here to listen via the BBC Radio 4 website (note that the audio can be streamed shortly after the program airs today).

Many thanks to Cicely and her talented team at Falling Tree Productions for spending a little time with us in the forest and on the air! Truly an honor.

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A photo tour of the 2022 Shelby Hamfest

On Friday, September 2, 2022, I had just enough time in my schedule to visit the Shelby Hamfest for a couple of hours.

The Shelby Hamfest–referred to, locally, as “The Grand-Daddy of them All”–has long been regarded as one of the largest outdoor hamfests in the southeast US.

Shelby Photo Gallery

Weather was ideal for the hamfest: clear skies, sunshine and very dry. It was quite hot, though! Attendance was much lower than I’ve ever seen at the Shelby Hamfest in the past, but then again this was also my first Friday attending; typically I visit on Saturday which is historically the busiest day.

Continue reading

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Small Unidirectional Loop Antenna (SULA) Part 3: Questions & Answers

Many thanks to SWLing Post contributor extraordinaire, 13dka, who brings us Part Two of a three part series about the new SULA homebrew antenna project. This first article describes this affordable antenna and demonstrates its unique reception properties. The second article focuses on construction notes. This third and final article will essentially be a Q&A about the SULA antenna. 

This wideband unidirectional antenna is an outstanding and innovative development for the portable DXer. I love the fact that it came to fruition via a collaboration between Grayhat and 13dka: two amazing gents and radio ambassadors on our SWLing.net discussion board and here on the SWLing Post. So many thanks to both of them!

Please enjoy and share Part 3:


Part 3: SULA Q&A

by 13dka

Q: Where can I ask questions, discuss all aspects of the the SULA or collaborate in its further development?

A: There is a thread dedicated to the SULA in the new SWLing.com message board: https://swling.net/viewtopic.php?t=55

Q: Since the antenna is “lossy”, what’s the point of having a “beam”?

A: The answer is once again “SNR”: First off, remember that the LNA is there to make up for most of the losses. Secondly, this is all about the noise pickup, 20dB less gain/more losses outside the main lobe means also a reduction of atmospheric/cosmic/whatnot QRN and of course everything manmade from all these sides. The wide horizontal lobe is more or less one hemisphere horizontally, but the flat-ish vertical pattern makes that only a slice of it. In other words, there will be less QRN and QRM pickup from the back and the top. The idea is that the SNR will ideally increase more than the preamp’s noise figure will cost and it often sounds like this is what actually happens. Of course it’s also nice that you can turn an unwanted signal down using the more or less pronounced notch in the backside pattern up to 21 MHz – also very helpful for direction finding.

Q: Do I need a rotor?

A: It depends. If you are one of the lucky few still having a low-QRM-environment at home and you want to put it in the backyard, you really may want to be able to turn it remotely. If you’re using it portable you can simply rotate the mast manually. If you have local QRM or can’t mount it very far away from your or other houses, you may want to rotate the back of the antenna towards that source, leave it at that position forever and enjoy what’s coming in on the pretty wide main lobe of the antenna. The horizontal lobe covers more or less half of the horizon, depending on your stations of interest and location you could get away with never turning the antenna at all.

Q: Is it better than the XYZ loop?

A: Hey, that’s exactly what I wanted to ask you! 🙂 Even though the SULA is very similar in appearance and performance to a good SML working in ideal (ground conductivity) conditions, the SULA is a pretty different animal with a different behavior: Regular small loops, besides being bidirectional, can lose quite a bit of their low angle sensitivity over “poor” ground while the SULA is supposed to be retaining its properties better over any type of ground. Also, while many SMLs are tuned for VLF through the lower portion of the shortwave, the SULA complements those with quite uniform (good) properties up to 30 MHz and beyond.

Q: I have an end-fed random wire or dipole strung up from the house to a tree etc. – can the SULA beat that?

A: That’s quite possible. To get low takeoff angles from horizontal wire antennas you need to string them up at least 1/2 wavelength high, that’s 20m/66ft on 40/41m, 10m/33ft on 20m and so on. If you can’t do that, the SULA may be your ticket to listen farther beyond the horizon. Also, wire antennas are often strung up to match space restrictions or avoid QRM vectors and that way you may end up with some directionality in directions you don’t want, or no directionality at all when the wire is too low. Another noteworthy point is the ground: For most horizontal antennas, better ground means a considerable higher takeoff angle so the dipole needs even more height for low angles. The SULA’s takeoff angle benefits a little from the better ground and only gets a little worse over poor ground.

Q: Do I really need an LNA?

A: I hope so? Of course it depends… if you are going to try this antenna in a very noisy environment, the LNA may have little to no benefit. The noise is limiting your “radio horizon” to very loud signals anyway and for those you may not need an LNA, ever. On the other hand, the antenna is very lossy and in a quiet environment where noise is not an issue at all, weak signals may drop below the sensitivity threshold of your receiver without the LNA. The less noise you have, the more you’ll be able to benefit from an LNA. You will also need one when your radio isn’t all that sensitive, similar to the requirements to run a YouLoop. Andrew kept the loop impedance as constant as possible in order to allow any low impedance coax preamp to work behind the Balun. Any LNA with 20dB of gain should do, as per usual, better stuff may bring better results.

Among the sparse offers for decent shortwave LNAs, the NooElec LANA HF seems to be the only decent LNA sold via Amazon. It’s comparatively low-cost and unlike the other offers on Amazon, ready to be powered via Bias-T or even via Micro-USB and therefore happy with 5V. Since I also had the balun from the same company I could simply connect that all with a couple of these cute little SMA plumbing bits and it worked. The downside is its unknown but perceivably low resilience against intermodulation (low 3rd-order intercept point), this is usually not a problem with such a small loop but it can be in the presence of nearby transmitters.

If you do have nearby transmitters and don’t mind sourcing an LNA from Europe, Andrew recently pointed me to preamps from here. They offer a moderately priced preamp with a 2N5109 transistor (based on the W7IUV design) for a high IP3 value and low noise, which is also available in PCB-only and fully assembled versions including a compartment. They also offer Bias-T boxes.

Another alternative would be https://www.sv1afn.com/en/product-category-5/-6.html – the design (using a GALI-84 MMIC) is promising more headroom than the LANA HF (which seems to use the lower voltage GALI-39), but needs 12V power like the W7UV preamp above. This LNA is available in a ready-to-use box as well.

Q: What is special/different about this antenna? There are already very similar designs!

A: It’s supposed to be simpler and more compact/portable, and it seems to deliver more consistent results over the entire coverage range in different usage environments than similar designs. The SULA was designed to be made with things that are particularly easy to obtain, or which were already obtained — many of us SWLs have some of that Nooelec stuff in our drawer anyway, even when (or because) we’re not habitual antenna builders and balun winders. Now making a better balun and buying a better preamp is not hard and could even bring better results but the point is that you don’t have to. In summary, this is not meant to be a miracle antenna, just number of compromises re-arranged to create a particularly uncomplicated, small, unidirectional loop antenna that aims for DX, for apartment dwellers and DX nomads like me.

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