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Many thanks to SWLing Post contributor, Pete Madtone, who shares the following recording of Cuban Numbers Station HM01 and notes:
Hi Thomas,
I was reading HF Underground earlier and a post on it mentioned that HM01 had gone a bit mad “10345 kHz is HM01 Cuban Lady with what sounds like a cuckoo clock“. Well I got up straight away and tuned in on VE7AV KiwiSDR and here it is in all it’s glory:
It almost sounds a bit reggaeish and even has what sounds like a little drum roll in parts.
If you’re feeling a bit down or tired today please have a listen as this’ll cheer you up!
All the best
Pete
Wow–thanks for sharing this recording with us, Pete! What a mystery behind this numbers station! Was the cuckoo intentionally or unintentionally added to the audio at the studio or transmitter level? What could that signify? Since the audio is tracking with the HM01 broadcast, it seems to be originating from the same transmitter.
Perhaps this adds more context or confusion: SWLing Post contributor Paul Walker has noted a number of audio “shenanigans” from Cuban broadcasts. Here are a few notes from his listening post in Alaska:
0320UTC Mon Aug 28 and Cuba is missing from 9700 for the 2nd time in a week, but instead of regular programming they’re broadcasting a horror movie of some kind. I can detect some kind of noise under the movie but it’s like a screech/hum, which is all I heard from 9700 last time it was on.
I should also add, after the first time i heard 9700 down on 9600, I subsequently heard it back on 9700 again…..so something’s up!
And now HM01 aka Suzie Cubana on 10345 is broadcasting……. along with Suzie counting down the numbers and the digital data bursts, theres a cuckoo bird cuckooing over the top of that audio.
In the 0500 UTC, Rebelde on 5025 kHz noted running TV audio too….some English language movie.
The domestic Radio Rebelde AM and FM web feeds appear to be running normal programming
Hi there, it’s been about three weeks now since I started DXing with the Eton Satellit and I thought it time to post an updated review, based on my experiences thus far, along with some recent catches. Noting that other radio hobbyists with a strong presence online have been posting neutral to negative reviews on this receiver, I would just like to point out, perhaps rather obviously, that no receiver is perfect and just as importantly, the criteria on which a portable radio is judged will be different from user to user, based on their listening habits. I am almost exclusively engaged in DXing with the Satellit, whilst others will be listening on the broadcast bands on a more casual basis. I know that for some, the ultimate quality and finish of a product is as important as performance and they would make their physical assessment in a very detailed manner. I on the other hand focus mainly on performance and as regards quality, I’m reasonably satisfied if it doesn’t fall apart in my hands, straight out of the box! That actually happened – and it’s sort of where I draw the line 🙂 I guess the point is, I try to respect everyone’s opinion, irrespective as to whether we are in agreement or not and I believe that’s healthy for the future of our hobby.
Ok, back to the Satellit. Firstly, I am able to confirm that in terms of ultimate sensitivity, this portable is very close to my Sony ICF-2001D – one of the most highly regarded portables ever made. The delta in performance between the two is most perceptible on the weakest of fading signals that intermittently deliver audio with the Sony, but can’t be heard on the Eton. On stronger signals, my experience is that either radio might provide the strongest and or highest fidelity audio. I have a series of comparison videos already in the can, which will be uploaded to the Oxford Shortwave Log YouTube channel soon.
In terms of selectivity, the digital bandwidth filters work very well, although I note that even on the narrowest setting (2 kHz) when operating in a crowded band, adjacent channel QRM can occasionally still sound quite pronounced, as compared to my Sony ICF-SW55 or ICF-2001D receivers. As regards synchronous detection, this is more of a hit-and-miss affair. Subscribers to my channel might notice that in nearly all of my reception videos featuring the Eton Satellit, I have not engaged the SYNC. That isn’t to say it doesn’t work, however, even with selectable sidebands, the SYNC mode often appears to increase the overall signal amplitude and noise floor, without positively influencing the SNR. However, it’s interesting to note that signals on the Satellit in AM mode often almost match the ICF-2001D in SYNC mode, in terms of overall SNR. More on that to come.
There are a number of ways to tune the radio; manually using the tuning knob (and this has a decent feel/ resistance to it), direct frequency input which requires pressing the ‘AM’ button to engage, automatic search and access to 700 memory locations, via 100 screen pages. In the real world – and by that I mean ‘my world’ which is most often in the middle of a field, or the woods, all of the above tuning options are as ergonomic as most of my other portables. With regard to SSB reception, there are fast, slow and fine tuning options with a maximum resolution of 10 Hz and this works very well to reproduce natural sounding speech in LSB and USB modes. The tuning speed/fine options are engaged by pressing the tuning knob inwards towards the set – quite a neat idea. With SSB and SYNC there’s always a little pause whilst the electronics engage – a set of chevrons appear on the screen to indicate the receiver is actually doing something. It’s similar to the Sony ICF-SW77 where you effectively toggle between SYNC USB and LSB and wait for lock. Not an issue for me, but it might annoy some, particularly those who have experience with the ICF-2001D, where SYNC engagement is instantaneous, if the signal is of sufficient strength. A small point, but worth making.
So, overall, a brilliant little radio that in my opinion is completely worthy of the ‘Satellit’ branding, at least in terms of ultimate performance. As I mentioned previously, one of the most experienced DXers I know, with more than 3 decades of listening to the HF bands and an owner of a number of vintage Satellit receivers noted that the Eton Satellit outperformed them – and by some margin. To further demonstrate this, I have included links to recent reception videos. In particular, I copied three of the regional AIR stations with signal strength and clarity that had never previously been obtained. I also copied HM01, the Cuban Numbers Station for the first time on the 11 metre broadcast band, Sudan and Guinea on the 31 metre broadcast band (a whopping signal from Guinea) and Polski Radio 1 on longwave. I hope you find them interesting. Since featuring the Satellit on my channel, one of two of my subscribers have purchased this radio and thus far have been very happy indeed with it’s performance.
Ultimately, I have to strongly recommend this portable to anyone interested in DXing and in particular those that embark on DXpeditions. I just hope that should you decide to buy one, you receive an example that performs was well as mine. Embedded reception videos and text links follow below, In the mean time and until my next post, I wish you all great DX!
Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.
Interest in shortwave numbers stations seems to wax and wane. We’re currently going through a period of increased interest (again) as I’ve been receiving quite a few messages from new readers asking where to find spy numbers and what type of shortwave radio is needed. Truth is, there are fewer and fewer numbers stations still on the air, though some are still quite reliable (like HM01).
The following article by Shane Harris at The Daily Beast is one of the better, more detailed, articles I’ve read in the popular press.
The Stupidly Simple Spy Messages No Computer Could Decode
by Shane Harris
When I was 10 years old, I found a shortwave radio in a crumbling old leather trunk where we kept family photos and other memorabilia.
As I spun the dial, tinny, modulating noises, like the song of an electronic slide whistle, emanated from the radio’s small speaker. Staticky cracks and pops competed for airtime. The sounds swished and swirled, unintelligible and unremarkable. But then, emerging through the clamor, was a voice.
I might have run right over it with the dial, but the voice’s rhythmic, steady pacing caught me up short. It wasn’t a deejay. Nor a commercial. And he wasn’t singing. He was just speaking. The same line, over and over again.
“7…6…7…4…3.” Pause. “7…6…7…4…3.”
I don’t remember if those were the exact numbers. But they were numbers. A repeated sequence which had no obvious meaning, and was entirely devoid of context. To find him here, amidst the screeches and howls of the shortwave frequencies, was like coming upon a man standing in the middle of a forest, talking out loud to no one.
How long had he been here? Who was he talking to? He had that officious tone of the recorded telephone operators who chastised you for dialing a wrong number. “Please hang up, check the number, and dial again.” And the same distracting static I’d heard in those messages filled the background. I wasn’t sure if he was speaking live, or if he’d been recorded and set loose to play into the air.
But there was an urgency to his tone. And a purpose. As if he were talking to me. Imploring. Listen. Hear me now. 7…6…7…4…3. Did you get that? 7…6…7…4…3.
While band scanning last Sunday (September 8, 2014) I stumbled upon the Cuban numbers station HM01 on 11,530 kHz at 17:30 UTC.
It’s always intriguing to hear shortwave numbers stations, but I prefer those that stick to pure vocal number strings; HM01 has numbers with digital bursts between number sets, which is a more fatiguing listening experience. Nonetheless, I kept it playing in the background as I tooled around the radio room Sunday afternoon, putting away supplies from my recent three week road trip.
Several times during the HM01 broadcast, I heard the audio (not the AM carrier) drop in the middle of numbers sets and digital bursts. This isn’t the first time I’ve heard hiccups on HM01 (see this post from last year, for example), so I wasn’t terribly surprised. Then, close to the top of the hour, HM01 audio dropped for a minute or so, then switched back to five-number sets with no digital bursts between; though I wasn’t copying the message, I suspected that someone in the studio intentionally, perhaps in frustration–or else accidentally–started the broadcast from the beginning again.
At this point, I started recording. The five-number sets continue for about a minute, then the carrier unexpectedly drops:
Since it was near the top of the hour, and HM01 broadcasts only tend to last one hour, I didn’t expect to hear the broadcast repeat–and it didn’t, at least on 11,530.
Via a little band scanning, I discovered that HM01 had unexpectedly migrated 105 kHz higher, to 11,635 kHz. This broadcast audio also begins a little awkwardly. You’ll hear the audio drop; I scan for a few seconds, then return to 11,635, and HM01 comes back. And this time, the numbers set sounds cleaner, with fewer problems. Here’s the recording:
I couldn’t help but chuckle over this…
Evidently, this message had some important content–otherwise they wouldn’t have re-broadcast the entire set the following hour, 105 kHz up from the original frequency (most likely protocol after technical difficulties). I imagine spies huddled around their radios, cursing at the interruptions and frustrated they had to listen for an additional hour; and I imagine the confusion at the broadcast site as they tried to diagnose the problem in a live broadcast. It’s during these little mistakes that numbers stations inadvertently tell us who they are (Radio Havana Cuba content has accidentally been played before on Cuban numbers stations).
Even if you’re not a Cuban spy, you too can receive secret messages sent by Havana to its spooks in Miami, Washington and around the world.
Every week, one short wave radio station in Cuba broadcasts 97 messages coded in fax-like tones. A computer program easily available to the public changes the tones into numbers, and the Cuban spies then decode the numbers into words.
A second Cuban spy station transmits 16 messages per week in the dots and dashes of the 175-year-old Morse code – secret messages to Havana spies who may be older or less technologically savvy.
[…]The busiest Cuban station these days, and the only spy station in the world that uses the fax-like tones, has been baptized as HM01 by amateur eavesdroppers who run Web pages like Spooks List, Spynumbers, ShortwaveSchedule and Enigma2000.
It transmits 11 to 14 messages per day, a total of 96 per week, on the same schedule each week but using a dozen different short wave frequencies, said Chris Smolinski, 41, a Maryland software engineer who monitors the spy stations as a hobby.
Each message almost always has 150 five-digit groups, so that eavesdroppers cannot measure the true length of the text. And some of the 10-minute transmissions are phonies, designed to mask the real number of spies receiving them.
Anyone can hook up a radio receiver to a computer, where the DIGTRX program – widely used by ham radio aficionados to send and receive lengthy texts, turns the tones into numbers. Spies then use secret computer programs to turn numbers into text.
“HM01 is an ideal system because you don’t have to teach any to anybody. The computer does all the work,” said Smolinski.
For the less computer-savvy spooks there’s the M08a station, which broadcasts 16 messages in Morse code, developed for the telegraph in 1836, on a set weekly schedule and on many of the same frequencies as Hm01.
On occasion, I hear the Cuban numbers station HM01 on 5,855 kHz on weekday mornings.
It seems that many of the mornings as I listen, I hear HM01 making mistakes or at least experiencing “technical difficulties” (click here for a recent case in point).
Though I don’t often record HM01, I did record it on the morning of September 20, 2013––and, yet again, I heard what seemed to be HM01 tripping over its own tongue.
Instead of the broadcast starting with numbers to identify the transmission, then implementing intermittent RDFT data bursts as per usual, this broadcast begins in the middle of a data burst, then shuffles awkwardly into a “normal” broadcast. I imagine an operative in the field scratching his or her head…
I’m always amazed by the remarkable talents and extraordinary knowledge of SWLing Post readers. Dirk Rijmenants recently commented on one of our Cuban spy numbers station postings:
[T]hanks for your work on this fascinating blog.
I have additional information on how and who used these Cuban numbers stations. I composed a paper based on FBI and court documents. “Cuban Agent Communications” can by found in the Papers section of my website.
I’ve read Dirk’s paper, which does, indeed, shed light on the process of receiving and decoding numbers. Most of all, it exposes the vulnerability and fallacy of using anything other than one-time decryption keys and single-use pads. Why? Most of what the FBI has learned about Cuban numbers came from laptops that were used to help decrypt coded messages–an unnecessary procedure when numbers can simply be decoded on note pads that can then be burnt or destroyed.
Many thanks to SWLing Post contributor, Pete Madtone, who shares the following recording of Cuban Numbers Station HM01 and notes:
