Category Archives: News

Patrizio seeks information about mystery signals he’s discovering across the HF bands

Many thanks to SWLing Post contributor, Patrizio Cardelli, who has discovered some interesting signals on the HF bands and is seeking information about them.

A little background: Patrizio asked me about these signals a few weeks ago and based on a quick glance at the spectrum and waterfall images I assumed it was DRM (Digital Radio Mondiale). I was wrong, of course. Had I looked at the actual frequency and bandwidth, I would have immediately realized is was not DRM. My email load has been so heavy as of late, and my time to reply at such a premium, I rushed through the reply–my apologies, Patrizio!

Patrizio followed up with this message:

Hello Thomas,

I hope this message finds you well. I wanted to share my recent radio exploration based on your advice. I followed your suggestion and investigated a sample signal within the 60-meter band, specifically settling on the one at 4.962 kHz.

I attempted to decode it using the Dream software but encountered no success. It seems this isn’t a Digital Radio Mondiale (DRM) transmission. To rule out local QRM (interference), I tested various Kiwi SDR receivers across Europe, both to the south and north of my QTH. Interestingly, I managed to pick up this signal everywhere, with a stronger intensity noted in the northern locations.

I’m eager to publish this article to find out if other Shortwave Listeners (SWL) have been able to decode this transmission. Additionally, I’d like to mention that similar signals, either continuous or intermittent, are present on various HF frequencies.

I look forward to any insights or experiences others in the community might have regarding this intriguing signal.

Audio sample:

While I recognize these signals now, and I’m sure most of you who cruise the bands have seen/heard these as well, Patrizio is a relatively new SWL, turns out, and I thought it might be fun exploring just what these signals are.

Readers: If you know what these signals are, please comment. Indeed, I’m sure there are a number of SWLing Post readers who have hands-on time with generating these signals as well in a past life or current career. Let’s explore!

Checking out BHI’s HP-1 and NCH headphones for DXing

10 Replies

By Jock Elliott, KB2GOM

As an oldster with a bit of hearing deficit, I am a big fan of anything that helps me to hear better when I am trying to tease out hard-to-hear signals, whether medium wave broadcast, shortwave broadcast, or single-sideband signals on the HF ham bands.

Toward that end, headphones help a lot. They deliver the audio signal directly into the ear canal while reducing distraction from external sounds. I had some inexpensive headphones from a big-box store, but I wondered if there were headphones that would be better suited for DXing.

So I contacted the folks at BHI to see if they had any headphones that would help with medium wave DXing. BHI is the British company that manufactures really effective noise cancelling products.

In response, the folks at BHI sent me their HP-1 Wired Stereo Headphones and their . . . NCH Active Noise Cancelling headphones . . . free of charge.

BHI describes the HP-1 Wired Stereo Headphones as “Comfortable Folding dynamic stereo headphones for Radio Communications,” and, in my view, they are just that. I found the HP-1 to be highly useful for medium wave and shortwave DXing. To my ear, they sound like they are biased toward high frequencies, with lower bass response than on the headphones I bought from the big-box store years ago. Because of the lower bass response, I find it easier to tease out faint signals on the airwaves, and the ear cups are comfortable for long-term listening. The cable is 1.9 m long and is terminated with an integral 3.5mm stereo jack plug. The HP-1 headphones are supplied with a 1/4″ stereo to 3.5mm stereo adapter.

The NCH Active Noise Cancelling headphones are a bit of a different beast: they are NOT designed to cancel noise on the broadcast signal you are listening to. Instead, they are designed to reduce external noise. According to the BHI website:

“The bhi NCH active noise cancelling headphones (ANC) do not work like our other DSP noise cancelling products but effectively reduce external ambient background noise enabling you to concentrate more and enjoy your listening experience when listening in a noisy environment. The over-ear style NCH headphones also give good passive audio isolation from external noise.”

These headphones are powered an AAA battery. There is a switch to turn the noise-cancellation circuity on and off, and there is an LED that lights when the unit is activated. The NCH headphones have a 1.25m detachable cable with 3.5mm jack plug (both ends).

So I tried out the NCH headphones while mowing the lawn with a gasoline-powered lawnmower and listening to an audio book on my digital recorder. Bottom line: they really work to significantly reduce (but not totally eliminate) an external noise source and make the listening experience more pleasant. And when they are not turned on, they work really well as ordinary headphones for DXing. Like the HP-1 headphones, they are comfortable and biased toward high frequency.

In the end, I found both these headphones worked well for their intended purpose, and I am happy to recommend them.

Video: Carlos receives Navtex from Argentina’s Navy, NOAA Radiofax, and Voice Forecast via USCG.

2 Replies

Many thanks to SWLing Post contributor, Carlos Latuff, who shares the following video and notes:

Receiving navtex, Radiofax and voice broadcasts in Rio de Janeiro, Brazil…

Click here to view on YouTube.

Wow, Carlos! What an amazing spot to play radio! Thank you for sharing!

Radio of the imaginary kind

Radio Exterior de España suspends shortwave service Dec 4-5 due to power cuts

Temporary suspension of shortwave emission

We inform you that the next few days December 4-5 Radio Exterior de España will be forced to suspend its shortwave broadcasts.

The reason: a cut in the electricity supply, beyond our control, which will affect the shortwave emitting center that Radio Exterior has in the town of Noblejas. The break is due to work that the Unión Fenosa company has to do in the electrical substation from that Toledo municipality and that will affect our facilities.

Consequently, shortwave emission will be suspended next Monday, December 4 and will last until Wednesday, December 6, which will be when the signal resumes.

We apologize for this incident, completely unrelated to the will of Radio Exterior de España.

Multiple CMEs and “Almost” X-Class Flare Incoming

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Many thanks to SWLing Post contributor, Troy Riedel, who shares the following item from Spaceweather.com.

MULTIPLE CMEs ARE COMING: At least three CMEs are heading for Earth following a series of magnetic filament eruptions (#1, #2 & #3) earlier this week. Their collective arrival could spark G2-class geomagnetic storms with mid-latitude auroras on Nov. 30th and Dec. 1st. This forecast does not yet take into account a possible CME hurled toward us by today’s almost-X class solar flare. Keep reading!

ALMOST-X CLASS SOLAR FLARE: Sunspot AR3500 erupted on Nov. 28th (1950 UT), producing an M9.8-class solar flare–only percentage points below category X. NASA’s Solar Dynamics Observatory recorded the blast:

A pulse of extreme UV radiation blacked out shortwave radio communications across the South Pacific Ocean and parts of the Americas: map. Mariners and ham radio operators may have noticed loss of signal at frequencies below 20 MHz.

This explosion almost certainly hurled a CME toward Earth. Confirmation awaits fresh data from SOHO coronagraphs. Stay tuned.

Click here to check out this news and much more on Spaceweather.com!

Radio Reminiscences . . . A Reader Participation Post

34 Replies

By Jock Elliott, KB2GOM

The other night, at 10 pm Eastern Time (0300 UTC), I was listening to Zoomer Radio from Toronto, Canada, on 740 kHz (medium wave) when a program called “Theatre of the Mind” came on. This wonderful program airs Monday through Friday and presents “Old Time Radio” programs from back in the day when radio dramas were a regular part of on-the-air fare.

As I listened, I got sucked through a hole in the space-time continuum. Instantly, I was no longer an official oldster with eight decades in his sights . . . now I was a grade-school kid on Saturday morning in the early 1950s looking forward to Big John and Sparky and Space Patrol coming up on the radio. Programs like that were a regular staple of my childhood.

It’s weird, but I can’t recall the content of any specific episode, but I can easily remember the joy I felt as the familiar strains of “The Teddy Bear’s Picnic” (Big John and Sparky’s theme) were broadcast.

Theatre of the Mind is a great moniker for radio dramas, because your mind is forced to fill in the details of the drama. The dialog, narrative description, and a few sound effects provide the clues, and, in the magic of your imagination, you provide the rest of the scenery and the setting, and it is great fun.

The power of the mind’s eye was brought home powerfully to me, in a funny way. Space Patrol was not just a radio program; it was also a television program. My family did not have a TV until I was in fourth grade. As a result, I never saw Space Patrol on TV until I saw it at a friend’s house. (Remember this was in the infancy of TV.) When I did, my overwhelming impression was: this is lame. The program that was wonderful in my mind on radio was considerably less so on live TV.

Later in grade school, I was given a germanium diode radio for Christmas. It became my tool for secretly monitoring “The Hawthorne Den” (jazz after midnight) under the covers. It was Big Time, Big Deal adventure for a boy my age . . . does it get better than that?!! It actually did, when my Dad brought home a Zenith Transoceanic.

So dear reader, check out Zoomer Radio on 740 if you can and enjoy Theatre of the Mind.

And now it’s your turn: what are your favorite radio reminiscences (modern or ancient like mine)? Please post them below.