Monthly Archives: May 2021

Upcoming Test Transmission of VORW Radio International

Dear Listeners,

On Tuesday May 18th, 2021 there will be a special test transmission of VORW Radio International via radio station WWCR. The test broadcast will be 1 hour in length and will feature mixed music, the purpose of this broadcast is to determine propagation and gauge if there is any interference from neighboring stations.

Here is the time and frequency:

9350 kHz – 2300 UTC (7 PM Eastern) Tuesday May 18th, 2021 – 100 kW WWCR Nashville, TN

Listeners in North America, Europe and West Africa should be able to receive the broadcast.

Reception reports will be extremely helpful and may be sent to [email protected]

Happy listening!

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Guest Post: Listening to Comb Stereo on Shortwave

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Many thanks to SWLing Post contributor, TomL, who shares the following guest post:

Comb Stereo on Shortwave

by TomL

Comb Stereo is an old technique being implemented over shortwave by the main sound engineer (Daz) at Radio Northern Europe International (RNEI). It ONLY works on Comb Stereo broadcasts which currently are RNEI, This Is A Music Show (WRMI), and one of the KBC broadcasts. It works in real-time or for SDR recorded files, too. It does NOT need a special HD/DAB+ radio.

A number of pluses for Comb Stereo on shortwave compared to digital:

“The bandwidth is the same as mono – So the SNR should be about the same as mono.

Selective fading doesn’t affect the comb bands much, so the balance is largely unaffected by selective fading notches.

The Comb Stereo artifacts are much like typical music effects of echo, chorus, fast reverb or room reflections.”

You can read about it here on Daz’ web site: homepages.ihug.com.au/~daz2002/tech/CombStereo/

You can also read Roseanna’s comment on the SLWing.com blog post: https://swling.com/blog/2020/04/rnei-now-broadcasting-in-comb-stereo/

An enhanced version is broadcast on WRMI for the RNEI time slot on Thursday morning (01:00 UTC) on 5850 kHz. It sounds very good and is not a pseudo-stereo like in my previous article, Music on Shortwave. For one thing, pseudo stereo is not real two-channel encoding and shifts vocals to one side, depending on which channels are chosen for high and low filters, which might get annoying after awhile. What seems amazing to me is that I have been able apply some minor noise reduction in Audacity and the Comb Stereo stays perfectly intact. It also still works after converting the WAV file to MP3 and sounds much like a regular FM broadcast. Furthermore, it does not require a special patented transmitter or receiver chip. It is compatible with regular mono transmitters.

If you want to try it, go to the RNEI web site; download and install the two files listed (VB Audio Cable and CombStereo Pedalboard x64):

https://rnei.org/stereo/

It is slightly tricky to setup and use or you will not hear anything (most Windows systems default to 48000 Hz these days). Right-click on the lower-right taskbar Sounds settings. Make sure to setup Properties – Advanced in both the VB-Audio Virtual Cable (Playback and Recording) and your output speakers (Playback) to 24-bit 44100 Hz processing.

Now run the app Pedalboard BAT file which corresponds to the broadcast you recorded (in this example “Start Comb Stereo for WRMI.bat”). Set the Options – Audio Settings:

Since the VB-Audio Virtual Cable takes over your volume output, adjust the volume of your Speakers in Windows’ Sounds – Levels (or you can adjust the volume in the sound player you are using, too):

Play the mono WAV or MP3 file and you should be hearing stereo!

When you are done, close Pedalboard2 and then disable the VB-Audio Virtual Cable for Playback and Recording to get your Sounds back to normal:

I cannot demonstrate what it sounds like unless you have the VB-Audio Virtual Cable and the Comb Stereo app setup and working properly. Here are snippets from recent RNEI broadcasts captured by my noisy porch antenna:

Here are links to the artists’ YouTube videos for comparison:

Kari Rueslåtten – https://www.youtube.com/watch?v=SFN4O3YrUG4

Ani Glass – https://www.youtube.com/watch?v=T63QS9enT-A

What is nice is that I can create a space-saving MP3 mono file and this setup will decode the stereo when run from the computer (sounds really nice on a stereo system with a subwoofer). Unlike digital, this analog-friendly stereo seems mostly immune to fading, has a minimum of digital artifacts, and will not go silent and “drop out” like digital does for long, annoying periods of time. It is not perfect stereo but audio players with features like Stereo Widener or Windows Sonic for Headphones can overcome some limitations. Perhaps content providers should consider Comb Stereo for all their shortwave radio shows since it is perfectly compatible with mono AM transmissions!

Enjoying the Music,

TomL

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Mystery Ugandan Clandestine On Shortwave

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Hi everyone! Paul Walker here, some of you may know me through various hobby circles via email and Facebook groups. I used to post quite regularly when I lived in Galena Alaska back in 2016 and 2017. I’m back in Alaska again, working as the Program Director for KSKO 89.5 and it’s half a dozen or so repeaters in the interior.

Back on Monday May 10th at 0601UTC here in McGrath, Alaska I ran across an unknown station on 15220kHz. The man was talking in African accented English but would randomly start talking in another language, which I at the time thought may have been French but very well could’ve been Swahili or some other language spoken in Uganda, I’m not a language expert. (audio below)

The man was going on and on about Uganda, “our brothers, our struggle, the government”. The audio cut out a few times for several seconds a time, seemingly because this was a live broadcast being fed live over the internet from whatever studio location he was at to whatever transmitter site was being used.

Around 0623UTC, the host sounded like he put his phone up to the microphone and played a Ugandan song of some sort from his phone. After that was over, two studio quality songs played.. The Spice Girls “2 Become 1” and Gabriel Kelly’s “Faith”. Those songs sounded like they were being played out from the transmitter site, not from a computer over the internet. They were clear with no audio hiccups. The transmitter went off around 0629/0630UTC.

A friend I was chatting with as we tried to figure out what this was said he had a decent signal on a Kuwaiti SDR and based on some triangulation work using other SDR, it seemed this was coming from Europe, suggesting Nauen or Lampertheim.

The man reappeared on 15170kHz at 1500UTC on Friday May 14th. I haven’t even been able to try and figure out a schedule. Evenings one day and mornings the next. I pretty regularly scan the dials and have only noticed him these two times, with thanks to Mauno Ritola in the WRTH Facebook group for the spotting of him on 15170khz.

I do have audio of the 15220 broadcast at this link:

https://drive.google.com/file/d/1J54RGCb00mIAHQ96O86f31T0l0GH0wNG/view?usp=sharing

I would love to know who this is, what transmitter site they’re broadcasting from and any contact information. A google search using the phrase “Uganda Clandestine Shortwave” came up with one hit, Radio Lead Africa and someone in the ODXA email group suggested Radio Munansi.

For anyone wondering, I’m using a Tecsun PL880 with a 8D battery powered DXE PreAmp and 2 Doxytronics tunable loops.. The cross that supports the antenna is sitting a few inches into 5 foot tall 2 inch wide PVC pipe which is then put in a trash can and tote container and filled with sand. Gotta use what I have on hand here in rural Alaska.

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Radio Waves: More RCI Services Come To An End, Pirate Radio Sound Tour, Shortwave Guitar Pedal, and Voyager 1 Detects Plasma “Hum”

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Radio Waves: Stories Making Waves in the World of Radio

Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers. To that end: Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Many thanks to SWLing Post contributors Marty, Richard Cuff, David Iurescia, and Doug Katz for the following tips:

RCI English section: goodbye (Radio Canada International)

Canada’s international broadcast service from the English language team of Radio Canada International has come to an end.

RCI, (originally the International Service, CBC-IS) was initially created towards the end of the Second World War. The purpose was to broadcast news and information from home via shortwave to Canadian military personnel fighting in Europe. It also began providing reliable news and information to recently liberated countries and to Germans still in the war.

That reliable news and information was considered of great value during the subsequent Cold War years, as several more languages were added to the service such as Russian, Ukrainian, Czech, Hungarian and Polish. Other languages sections included as Brazilian Portuguese and Japanese. With 14 language sections in 1990, and some 200 staff, the full English and French newsroom provided news of interest and importance for each language section specifically targeted to each of the various broadcast regions around the world.

Following a major budget cut of some 80 per cent in 2012, the shortwave and satellite service was terminated along with the majority of staff including the newsroom and some language sections. In recent years, only Chinese (Mandarin), Arabic, and Spanish remained along with English and French. RCI was transformed into a much smaller internet-based operation consisting of three people per language section.

In December 2020, the domestic public broadcaster CBC / Radio-Canada announced that the English and French sections of RCI would close for good in May. In their place curated stories from the domestic English and French public broadcaster will be provided.

A manager will now oversee the staff of eight who will adapt curated stories from the CBC and Radio-Canada into Mandarin, Arabic, and Spanish, along with Punjabi and Tagalog.

An effort was and is being made by the RCI Action Committee to preserve and even expand the service which has garnered great support from a former prime minister, former diplomats and many academics, but the end date has come. This is the last entry by the RCI English section.

From the English Section consisting of Lynn, Marc, and Levon, faithful and long-time popular replacement Terry Haig, and recently also Vincenzo Morello, and the many others over the all those years, we thank you for having shared our stories over these many years.[…]

The Pirate Radio Capital: A sound tour with David Goren, radio producer and audio archivist (CRJ.org)

In 2018, David Goren, a radio producer and audio archivist, created the Brooklyn Pirate Radio Sound Map to collect the sounds of dozens of pirated broadcasts from across the borough. Pirate stations earn their name by hitching a ride on already licensed radio frequencies that typically cost commercial stations millions of dollars to acquire and set up. Nowhere in the country are there more pirate radio stations than in New York, where they provide a vital service to immigrant populations.

Goren estimates that New York has about a hundred pirate stations, transmitting from rooftops and attics to listeners seeking news from around the city and back home, as well as

entertainment and religious programming. The broadcasts bypass socioeconomic barriers and provide a means to seize control of the flow of information. But they are now at risk of extinction: Before Donald Trump left the White House, he signed the Pirate Act, which increased the authority of the Federal Communications Commission to fight pirate operations through mandatory sweeps in cities with high concentrations of pirate radio use. Pirate stations today face fines of up to two million dollars. “The people running these stations, they don’t have two million dollars,” Goren said. Broadcasters that don’t make it onto his sound map could be lost forever.

Click here to read the full story and listen to the audio tour with David Goren.

Shortwave effects pedal (Recovery Effects)

Inspired by espionage devices used during World War II and the Cold War, Shortwave transforms audio into clandestine operations of the past; Russian number stations, mysterious sounds transmitted by radio, and eerie sounds stored on early portable recorders.

Choose between 2 types of noise and interference, and control it with the Exposure parameter. Velocity and Focus control the amount of pitch stabilization. Shortwave will add an interesting emotional response and atmosphere to dry, simple sounds, or destroy a signal like no other fuzz pedal can.

Hand-made in Seattle, WA. Shortwave operates on a standard “Boss” style 9vdc power supply (not included), but can also run at 18vdc for additional headroom. True bypass switching. Included a limited-lifetime warranty.

Enclosure size: 4.77″ x 2.6″ x 1.39″

In the emptiness of space, Voyager 1 detects plasma ‘hum’ (Cornell.edu)

Voyager 1 – one of two sibling NASA spacecraft launched 44 years ago and now the most distant human-made object in space – still works and zooms toward infinity.

As the craft toils, it has long since zipped past the edge of the solar system through the heliopause – the solar system’s border with interstellar space – into the interstellar medium. Now, its instruments have detected the constant drone of interstellar gas (plasma waves), according to Cornell-led research published May 10 in Nature Astronomy.

Examining data slowly sent back from more than 14 billion miles away, Stella Koch Ocker, a Cornell doctoral student in astronomy, has uncovered the emission. “It’s very faint and monotone, because it is in a narrow frequency bandwidth,” Ocker said. “We’re detecting the faint, persistent hum of interstellar gas.”

This work allows scientists to understand how the interstellar medium interacts with the solar wind, Ocker said, and how the protective bubble of the solar system’s heliosphere is shaped and modified by the interstellar environment.

Launched in September 1977, the Voyager 1 spacecraft flew by Jupiter in 1979 and then Saturn in late 1980. Travelling at about 38,000 mph, Voyager 1 crossed the heliopause in August 2012.

After entering interstellar space, the spacecraft’s Plasma Wave System detected perturbations in the gas. But, in between those eruptions – caused by our own roiling sun – researchers have uncovered a steady, persistent signature produced by the tenuous near-vacuum of space.

“The interstellar medium is like a quiet or gentle rain,” said senior author James Cordes, the George Feldstein Professor of Astronomy (A&S). “In the case of a solar outburst, it’s like detecting a lightning burst in a thunderstorm and then it’s back to a gentle rain.”

Ocker believes there is more low-level activity in the interstellar gas than scientists had previously thought, which allows researchers to track the spatial distribution of plasma – that is, when it’s not being perturbed by solar flares.[…]

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Guest Post: Methods for discovering and recording online radio programming for later listening

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Many thanks to SWLing Post contributor, Bill (WD9EQD), who shares the following guest post:

Time Shifting Radio Programs for Later Listening

by Bill (WD9EQD)

There are quite a few programs on shortwave that I enjoy listening to for the actual program content. If I am lucky, I will receive a strong enough signal to really enjoy the experience. But all too often, I either can’t directly receive the program or conditions are such that listening is just not enjoyable. What I was looking for was good quality sound that I could listen to on my schedule.

I could always just go to the station website and listen to the live stream of the program. But what if there are two programs on different stations at the same time? I would have to choose which one to listen to. What I needed was a way to listen to the program on my schedule.

This write-up will be presenting several ways this can be accomplished.

Is the Program Streamed?

In many cases, it is possible to go to the program’s website and then listen to the latest program or even an archive of past programs at your convenience. Some examples are:

Hobart Radio International http://www.hriradio.org/

Radio Emma Toc https://www.emmatoc.org/worldserviceindex

VORW International https://soundcloud.com/vorw

AWR Wavescan http://eu.awr.org/en/listen/program/143

Blues Radio International: http://www.bluesradiointernational.net/

This is a Music Show https://thisisamusicshow.com/

Radio Northern Europe International: https://www.mixcloud.com/RadioNorthernEurope/

Alt Universe Top 40: https://www.altuniversetop40.com/links

International Radio Report https://www.ckut.ca/en/content/international-radio-report

World of Radio http://worldofradio.com/

The Shortwave Report http://www.outfarpress.com/shortwave.shtml

Lost Discs Radio Show https://www.lostdiscsradio.com/

Grits Radio Show https://archive.org/details/gritsradioshow2020

Le Show with Harry Shearer http://harryshearer.com/le-show/

Can the Program Be Downloaded?

All HRI programs are available on their Archive.org page.

Quite often, the program’s web site will also let you download the program for listening at a later date. Some examples are:

Hobart Radio International has an Internet Archive page where you can listen to and download their previous programs: https://archive.org/details/@hobart_radio_international

Radio Emma Toc has a button for “broadcast & internet relay services wishing to air our programme”.

But anyone can download the program.

VORW International: https://soundcloud.com/vorw

(Note: You will have to sign into Soundcloud to be able to download the files)

AWR Wavescan: http://eu.awr.org/en/listen/program/143

Your Weekend Show: https://open.spotify.com/show/2RywtSHWHEvYGjqsK6EYuG

International Radio Report https://www.ckut.ca/en/content/international-radio-report

World of Radio http://worldofradio.com/

The Shortwave Report http://www.outfarpress.com/shortwave.shtml

Lost Discs Radio Show https://www.lostdiscsradio.com/

Grits Radio Show https://archive.org/details/gritsradioshow2020

Le Show with Harry Shearer http://harryshearer.com/le-show/

WBCQ has a link to an Archive of some of their programs. Just click on the Archive link and you will go to Internet Archive where there are a lot of programs that can be streamed or downloaded. The programs include:

Adventures in Pop Music
Analog Telephone Systems Show
B Movie Bob
Cows in Space
Godless Irena 1
Grits Radio Show
Lost Discs Radio Show
Radio Timtron Worldwide
Texas Radio Shortwave
The Lumpy Gravy Show
Zombies in your Brain
Vinyl Treasures
Plus many, many other programs…

Does the Program Have a Podcast?

Check to see if the program has a podcast. Many programs do and this makes it easy to always have the latest program updated into my favorite podcast program.

AWR Wavescan is available on a number of podcasting platforms

Some programs that have podcasts:

Hobart Radio International
AWR Wavescan
Blues Radio International:
Your Weekend Show
International Radio Report
World of Radio
The Shortwave Report
The Lost Discs Radio Show
Le Show with Harry Shearer

Directly Record the Stream While It Is Being Broadcast

This method is a little more difficult and requires some setup. The method is to record the program directly from the internet stream of the station as it is broadcasting the program. Once set up, the procedure is completely automatic and will continue to capture the program until it is disabled in the scheduler.

Let’s walk through a typical program that we want to record. I like Alan Gray’s “Last Radio Playing” program on WWCR. It is broadcast weekly on Wednesday at 6pm Central Time on 6115. While I can receive the program over the air, it’s not very good reception, so I usually just stream it off the internet.

What I want to do is to set up an automatic computer program that will connect to the stream on Wednesday night, record the stream for one hour and then disconnect. I use the program StreamRipper which can run on either Linux or Windows.

http://streamripper.sourceforge.net/

Since I have a spare Raspberry Pi 4 computer, I chose to use the Linux version. The following description is based on Linux. A similar method I’m sure could be done with the Windows version.

Fortunately, StreamRipper is in the current software repository for the Raspberry PI and I could just install it with having to do a compile. I’m sure other Linux distributions probably also have it in their repository. It was a simple matter to install it. In Linux, Streamripper is run from the command line in a terminal window.

A typical command line for SteamRipper is:

streamripper station_URL_stream –a “filename” –A –d directory_path -l seconds

where

station_URL_stream is the http address of the audio stream. Determining this can sometimes be challenging and some methods were recently discussed in a SWLing Post:

https://swling.com/blog/2021/04/robs-tips-for-uncovering-radio-station-stream-urls/

–a says to record the audio as a single file and not try to break it up into individual songs.

“filename” the filename of the resultant mp3 file goes here in quotes

-A again says to create a single file.

-d tells it the directory path to store the mp3 file. Place the full directory path after the –d

-l specifies how long to record. Enter the number of seconds after –l.

(note: this is lower case letter l)

For Last Radio Playing, the command line is:

streamripper http://67.225.254.16:3763 –a “Last Radio Playing” –A –d /home/pi/RIP/wwcr –l 3600

when executed, this would connect to the URL stream, record for 3600 seconds (60 minutes) and then disconnect from the stream A file called “Last Radio Playing.mp3” would be in the wwcr1 directory.

Save this command line to a shell file, maybe wwcr.sh. Then make this shell file executable.

Last is to enter a crontab entry to schedule the shell file wwcw.sh to be run every Wednesday at 6pm ct.

At the command line, enter crontab –e to edit the cron table.

Add the following line at the end:

0 19 * * 3 /home/pi/wwcr.sh

then exit and save the crontab file.

This line says to execute wwcr.sh every Wednesday at 1900 (my computer is on eastern time).

There are many ways to enhance the shell script. For example, I have added the date to the mp3 file name. My wwcr1.sh shell script is:

NOW=$(date +”%Y-%m%d”)

# WWCR1 Last Radio Playing

# Wednesday 7-8pm et

streamripper http://67.225.254.16:3763 -a “$NOW Last Radio Playing” -A -u FreeAmp/2.X -d /media/pi/RIP/wwcr1 -l 3600

This will create a MP3 file with the date in the file name. For example

2021-0505 Last Radio Playing.mp3

Note: I named the file wwcr1.sh to denote that WWCR transmitter 1 was being streamed. Each of the WWCR transmitters have different stream URL.

Most radio streams work fine with the default user agent but WWCR required a different user agent which is why the –u FreeAmp/2.X is added. Normally, –u useragent is not required. The default works fine.

For each program, just create a similar shell file and add it to the cron scheduler.

Streamripper is very powerful and has many options. One option is for it to attempt to divide the stream up into individual files – one for each song. Sometimes this works quite well – it all depends on the metadata that the station is sending over the stream. I usually just go for a single file for the entire show. Some stations are a little sloppy on whether the program starts on time – sometimes they start a minute early and sometimes run a minute over. The solution is to increase the recording time to two minutes longer and then specify in the crontab file that the show starts a minute early. It’s easy to adjust to whatever condition might be occurring.

Recording the BBC

I have found that the BBC makes it more difficult to use this procedure. For one thing, they have just changed all their stream URL’s. And they have decided NOT to make them public. When they did this some of the internet radios broke since they still had the old URL’s. Of course it didn’t take long for someone to discover and post the new stream URL’s:

https://gist.github.com/bpsib/67089b959e4fa898af69fea59ad74bc3#file-bbc-radio-m3u

I have tested the Radio 4 Extra stream and it does seem to work. For how long is anyone’s guess.

I found that while streamripper did seem to work on BBC, all the mp3 files came out garbled. So the method above doesn’t seem to work with the BBC.

I went back to the drawing board (many hours on Google) and discovered another way to create a shell script that can be scheduled to record a stream. This involves using the programs mplayer and timelimit.

First step is to install the programs mplayer and timelimit to the Linux system. mplayer is a simple command line audio and video player. timelimit is a program that will execute another program for a specific length of time.

First I created a shell script bbc30.sh:

#!/bin/bash

NOW=$(date +”%Y-%m%d-%H%M”)

# BBC Extra 4 – 30 minute program

timelimit -t1800 mplayer http://stream.live.vc.bbcmedia.co.uk/bbc_radio_four_extra -dumpstream -dumpfile /media/pi/RIP/$NOW-bbc.mp3

Note: The bold line above is all on one line in the shell file.

This script will execute the timelimit command. The timelimit command will then execute the mplayer command for 1800 seconds (30 minutes).

The mplayer command then connects to the http stream; the stream instead of playing out loud is dumped to the dumpfile /media/pi/RIP/$NOW-bbc.mp3

The crontab entry becomes:

30 23 11 5 * /home/pi/bbc30.sh

In this case, the program on May 11 at 2330 will be recorded.

Summary

In conclusion, Podcasts are the easiest way to get the programs. But automatically recording directly from the station stream is really not that much harder to do. Just be careful. It’s very easy to accumulate much more audio than you can ever listen to in this lifetime.

One final note. The use of a Raspberry Pi makes this a very easy and convenient method. I run the pi totally headless. No keyboard, mouse or monitor. It just sits on a shelf out of the way and does it thing. I either log in using VNC when I want the graphical desktop, Putty for the command line, or WinSCP for transferring files. The Pi stays out of the way and I don’t end up with another computer system cluttering up my desktop.

Besides recording several shortwave programs, I use Streamripper to record many FM programs from all around the United States. It’s great for recording that program that is on in the early morning hours.

Bill WD9EQD

Smithville, NJ

Thank you for sharing this with the SWLing Post community, Bill! This weekend, I’m going to put one of my RPi 3 units into headless service recording a few of my favorite programs that aren’t available after the live broadcast. Many thanks for the detailed command line tutorial!

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WRTH A21 season broadcasting schedule updates available as free download

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Many thanks to Sean Gilbert, with the World Radio TV Handbook, who shares the following announcement:

WRTH is pleased to announce that the A21 (Summer) season broadcasting schedules for International and Clandestine/Target broadcasters are now available for download, free of charge.

This file is in PDF format so you will need software capable of reading the Adobe PDF format (such as the free Adobe Acrobat reader, amongst others).

Not only do you get the full schedules, extras included with the file are:
Broadcasts in Selected Languages (English. French, German, Portuguese, and Spanish); International DRM broadcasts (yes, there are still some around); International Broadcasting Frequency list; International Transmitter Sites, with lat/long; WRTH Target Areas and religious stations cross-reference table (You can find out which country each station is based in and where to find their schedule as that is not always as obvious as it may seem).

Please visit www.wrth.com and follow the links to the download page.

We hope you find this a useful file, both as a stand-alone product and as an accompaniment to the printed WRTH volume.

Feel free to pass this information on to all your radio friends and your social media groups, etc.

73 and happy listening from the WRTH Editorial Staff.

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The Chameleon CHA RXL amplified wideband loop antenna

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A few weeks ago, Chameleon Antenna sent me a pre-production model of their new wideband magnetic loop antenna called the Chameleon CHA RXL.

I’ve evaluated and reviewed a number of Chameleon’s ham radio antennas (primarily on QRPer.com). I find that the quality of their products are second to none. Price-wise, they tend to be at the top of the market, but keep in mind they machine and manufacture all of their antennas here in the US and they’re incredibly rugged; indeed, military-grade. And in the spirit of full disclosure, I’m proud Chameleon has been a sponsor the SWLing Post and QRPer.com since last year. My sponsors are by invite only and focus on companies I trust with our radio community’s business.

When Chameleon shipped the CHA RXL to me, it wasn’t from their factory, it was directly from the field: Fort Irwin, to be exact.

(Source: NTC Operations Group, Ft. Irwin)

This CHA RXL sample had been used by NTC Operations Group Fort Irwin (who, incidentally, won QRPX this year–click here to read the PDF report).

I was told that the condition of the antenna could be very rough after the QRPX because it had essentially been sandblasted in the desert winds. I was also told that someone accidently transmitted 5 watts into it at some point but it didn’t seem to harm it (for the record, like all amplified receive-only loops, it’s not designed to take RF).

Tony (W0NTC), who was one of the Ft. Irwin radio ops, sent me this note as he dropped off the shipment at Fort Irwin’s FedEx:

“Had a blast with [the CHA RXL], and it was absolutely critical while I was operating in the Army HF Low Power Competition (think tons of high powered MARS stations piling up and drowning out the 20W or less competitors). It absolutely crushed some localized RFI from a huge building I operated behind, and the receive on it I can only describe as “layered” in that I could hear stations somewhat clearer than usual if they transmitted simultaneously. Receiver I used was the IC-705 with default Auto Notch and Noise Reduction.”

Tony volunteered all of this info–I never asked him how it performed.

A few days later, I wasn’t sure what to expect when I opened the box although I knew that my operating locations were nowhere near as cool as its position next to a Humvee at Fort Irwin in the photo above!

I pulled the CHA RXL out of the box and it looked cosmetically flawless to me.

Frankly, there’s not a lot to get damaged. The 36 inch diameter loop is made of rigid aluminum and has a Navy gray powder coating. The preamplifier unit is completely sealed and made of a high-impact plastic/PVC type material. The steel loop is attached to the preamplifier loop flanges with wing nut connectors.

The only potentially vulnerable part of the antenna system is the Bias-T box which would normally be located in your shack close to your receiver.

If I mounted the CHA RXL permanently outdoors, I would use Coax Seal around the BNC connection point, of course.

Although the CHA RXL has a supplied mounting bracket for permanent installations, I love the fact that the preamp box has a 1/4” x 20 threaded camera socket on the bottom. This makes for a brilliant portable loop because it can so easily be mounted on a standard heavier-weight tripod! All antenna manufacturers should give us tripod mount options when possible.

On the air

One of the reasons amplified receive loop antennas have become so incredibly popular over the past couple of decades is because they do an amazing job mitigating radio frequency interference (RFI) a.k.a. “QRM.” If you live in a neighborhood with significant radio interference, you really should consider some form of loop in your antenna arsenal.

Ironically, at home, I live in pretty much an RFI-free zone. I’m surrounded by tens of thousands of acres of national forest, so I’ve only used amplified loop antennas in the past for mediumwave DXing–mainly, when I wanted to take advantage of their amazing ability to null out unwanted signals.

Many years ago, I purchased a Pixel Loop Pro antenna (now under a different name via DX Engineering), mounted it outside where it lasted almost a year before a bear decided to pull it down and chew through the coaxial feedline. He/she did so with enough energy that it ripped down the loop and damaged the connector end of the Pixel’s pre-amp. This all happened when our family was travelling for two months in Canada. Why bear, why?!? But I digress…

The CHA RXL version I was shipped has one single rigid loop–the “EU” version’s loop comes in two pieces (for easier shipping/transport)–but I had no problem fitting the entire assembled loop in the back seat of my Subaru or my truck (as long as no one was sitting back there at the time). If you plan to travel with your loop a lot, consider the “EU” version!

I’ve taken the CHA RXL to my parent’s home a couple of times and enjoyed doing a little mediumwave and shortwave listening. Inside the house, the loop would attenuate RFI nicely, but when outside it would all but eliminate many sources of RFI.

At their house, I primarily used my Icom IC-705 for cruising the bands (being careful, of course, to disengage the transmit function).

Listening time in my hometown, though, was very limited. Since the CHA RXL is so portable, I decided to set it up at home on our porch for a few days, giving me an opportunity to test both the Sangean ATS-909X2 and Tecsun H-501x with an external antenna.

I’ve especially appreciated using the CHA RXL on mediumwave. Even from our screened-in porch, I can rotate the loop and use its excellent nulling properties to pick out multiple station IDs on crowded frequencies.

I’ve spent time on shortwave, too, and found that it certainly gave these two portables a signal boost.

In fact, it was by using the CHA RXL that I discovered the audio level difference between AM and SSB on my ATS-909X2 is very minimal when an external antenna is connected.

I’m sure you’ll hear the CHA RXL in action when I post audio clips and recordings in upcoming reviews.

Summary

If I owned a CHA RXL loop, one of the first things I’d do is build a power cord for it with an in-line fuse and terminated with an Anderson Powerpole connector. Since the operating voltage of the Bias-T is 12-14 VDC, it would pair perfectly with one of my Bioenno LiFePo4 batteries, offering a power source with longevity in the field–ideal for a group LW/MW/SWL DXpedition.

It’s difficult for me to truly comment on the loop’s performance because I don’t have another loop at present for comparison. I can say that it’s amazing on mediumwave, where I’ve spent much of my listening time this past week. I believe shortwave reception has been at least on par with my former Pixel Loop, if not better. It’s hard to say, in truth, because propagation conditions have been so poor lately. The CHA RXL loop does effectively mitigate noise!

I’m not sure if the CHA RXL is currently on backorder or not, but I would suggest you check out the product page on Chameleon’s website and possibly contact them if you’re interested. They’ve a number of options and accessories to consider.

Click here to check out the CHA RXL at Chameleon Antennas ($490 US).

One thing for sure: this must be one of the most rugged and durable RX loop antennas on the market. In addition, that Navy gray powder coating helps this rigid aluminum loop disappear against the sky. I believe you could strategically mount this loop and the friendly neighborhood association may never notice–it’s pretty stealthy. Speaking of which…

Josh’s CHA RXL install and demo video

Josh over at Ham Radio Crash Course recently installed a CHA RXL on his house and tested it on several bands, comparing it with a number of his external antennas: