Any Shortwave Radio Tips for a Noob Considering the Hobby?

[bd139]

Indeed. The older modes seem quite popular due to the simplicity as well. I ONLY operate CW which is older than AM

The glorious thing about this hobby is the scope and the fact you can escape back to the dark ages if you want to away from computation and complexity.

[edy]

I noticed something interesting with the Tecsun PL-310ET during the auto-scan ETM function. It normally starts at 2300 and then goes up by 5 kHz (at least on the display) until it gets to 21,950 kHz. However when I've looked at the display I noticed whenever it switches bands it "jumps" over a whole swath of frequencies. I recorded the scan on video and played it back in slow motion and found the following ranges are covered by the ETM auto-scan (the first label, e.g. "120m" is what is shown on the display as the band, and second range e.g. "2300-2550" is the range of frequencies is scans through):

120m: 2300-2550
90m: 3150-3450
75m: 3850-4050
60m: 4700-5100
49m: 7500-6300
41m: 7080-7600
31m: 9200-10,000
25m: 11,450-12,200
22m: 13,500-13,900
19m: 15,000-15,900
16m: 17,450-17,900
15m: 18,850-19,100
13m: 21,430-21,950

So basically it is skipping the following ranges of frequency when scanning (although I can tune in manually if I choose to):

2551 - 3149
3451 - 3849
4051 - 4699
5101 - 5699
6301 - 7079
7601 - 9199
10,001 - 11,449
12,201 - 13,499
13,901 - 14,999
15,901 - 17,449
17,901 - 18,849
19,101 - 21,429

Now I don't know enough about SW bands and frequency ranges agreed upon internationally for certain broadcasts, but that is a lot of spectrum that is being ignored by the ETM function, yet I can manually select those and scan through them. Any idea why this would be implemented this way?

I understand the Tecsun displays the "meter" bands strictly in these steps: 13, 15, 16, 19, 22, 25, 31, 41, 49, 60, 75, 90 and 120. However, within each range there is a big variation in wavelength anyways that is scanned. For example, from 2300- 2550 we have 130.3m to 117.5m whereas Tecsun labels it the 120m band. Similarly, for every other band we have a range. Yet the display doesn't say 17 or 18m bands. It will display 16m and then jump to 19m. Here is the display and strict wavelength conversion:

22m: 13,500 (22.21m) - 13,900 (21.57m)
19m: 15,000 (19.99m) - 15,900 (18.85m)
16m: 17,450 (17.18m) - 17,900 (16.75m)

So I understand 22m would be appropriate since 21.57-22.21 is centered around 22m. But 19m range has almost 20m, and the 16m range is mostly centered around 17m even!    Perhaps there is a convention or some kind of assigned "bands" that relate frequency to meters, and the Tecsun was programmed to those and to skip over sections that are "not allowed" to be used for broadcasts. It seems strange that they would implement it this way and that they wouldn't just calculate the wavelength and be more accurate when tuning... for example, write down 17m (instead of 16m) when I am tuned to 17450 kHz.

Here is what I found on "short-wave.info" website, and I quote:

Band       Frequency Range    Notes
120 metres   2300-2495 kHz   Only used in tropical areas. (Strictly speaking not a short-wave band but a medium wave one!)
90 metres   3200-3400 kHz   Only used in tropical areas.
75 metres   3900-4000 kHz   Not used in the Americas. Restricted to 3950-4000 kHz in Europe, Africa and the Middle East.
60 metres   4750-4995 kHz   Only used in tropical areas.
49 metres   5900-6200 kHz   
41 metres   7200-7450 kHz   Restricted to 7300-7450 kHz in the Americas.
31 metres   9400-9900 kHz   
25 metres   11600-12100 kHz   
22 metres   13570-13870 kHz   
19 metres   15100-15800 kHz   
16 metres   17480-17900 kHz   Highest frequency band in common daily use.
15 metres   18900-19020 kHz   Virtually unused!
13 metres   21450-21850 kHz   
11 metres   25670-26100 kHz   Little activity other than tests of local digital services.

So according to this chart, the Tecsun is basically scanning those ranges (with about 50 kHz additional bracket on either side). I guess there is nothing in between those bands so that is why it skips them.

NOTE:   It seems like the batteries in this Tecsun never die. I have been using the radio a lot over the past week, with NiMH batteries installed. It is still showing full bars on the battery meter. How long do these things last? I can't believe it!

[edy]

Just an update... It's been a prolific few days since I last posted! I got some help from a few radio/HAM YouTubers and received a few email replies from some folks who built antennas. I will post what I can here and then probably another post to add more photos later. Here is one of the articles in particular that I followed closely to calculate and build a loop antenna for LW range:

https://www.randombio.com/loopantenna.html

I have also attached an EXCEL spreadsheet I put together to help calculate the curves and figure out properties of various size loop antennas. I decided to go for a small antenna at this point due to storage/portability and not to upset the wife too much.  The dimensions are as follows... it is 26 cm diameter square, and 22 cm deep, with about 42 turns using 24 AWG stranded wire. This uses up about 43 m of wire, or 143 feet. I built the frame out of spare wood and dowels I had sitting around. I notched the dowels (made grooves) about 0.5cm apart so the windings of wire would sit in the grooves and not slide around as much:



Here it is with a few measurements:





Next I needed to plug all the numbers in and figure out what kind of tuning range capacitance I will need to get from about 153 to 513 (the LW tuning range of my Tecsun). Here is a graph showing this using the EXCEL spreadsheet I attached:



You will notice in the graph that I have a "meas" and "calc" for pF. That's because I had a theoretical inductance based on the equations for a loop antenna from that previous article, and I also measured the inductance using one of those cheap LCR meters I had around. It was actually not too far off, I was surprised:



So based on the calculations I needed to be able to vary my capacitance from about 200 pF to about 2500 pF. Not having a convenient source nor the budget to get a proper broadcast gang air dielectric variable capacitor, I decided to use a bunch of trimmers from the local electronics shop and switches to make something that I could tune into that wide range of capacitance. I bought a prototype "Schmart" board and tried to figure out how to use it, as this was MY FIRST TIME prototyping on a PCB!!! (I always cobbled stuff together before on a breadboard). 

Here's what I was thinking to do:



So with both switches OFF (at the far right) and the trimmers all set to their lowest (8, 15, 15, 15), I have about 53 pF. The calculations also showed I have a distributed capacitance in the loop of 15 pF, so now I'm up to about 68 pF. So I figured if I add a 151 pF cap (the beige colored cap seen below) it will set the "floor" base capacitance to 219 pF.

Now, when I am playing around with the trimmers I can go up to a maximum of 160 pF on the 3 larger green trimmers, and 40 pF on the smaller white one. So that gives me a range of about 520 pF of variability in the trimmers. So with all trimmers to full, I get up to 686 pF without invoking any of the "switchable" caps. So far so good?

Now, I want to go into the next range, I dial all my trimmers back to the lowest values, switch in my 561 pF cap (the single blue one in the middle and you can see one of the switches is lined up with it), and now I am at 780 pF and can trim up to 1247 pF. Unfortunately this means I have a "dead spot" between 686 pF and 780 pF. I would need to add another trimmer in here to bridge the "gap" between my ranges. Either that or make the jump to the next range smaller (instead of 561 pF, I can get 2x221 pF or 442 pF jump). Either way, I would need components I didn't have. I can always modify later. Adding a trimmer (another 40-160 pF) in parallel to the circuit would solve this problem if I need, I would just lower the "base" floor cap down so compensate for the extra 40 pF on the lowest end of the newly added trimmer.

In any case, if I turn off the 561 pF switch and invoke the other switch instead (hooked up to 2 parallel 561 pF or 1122 pF... you can see the pair of blue caps next to the other switch) then I can tune my next range from 1341 pF to 1808 pF. Then if I invoke BOTH switches, I'm basically now adding 1683 pF (3x561pF) so 1887 pF and reach a maximum of 2369 pF. So my ranges are as follows:

219-686 pF
780-1247 pF
1341-1808 pF
1887-2369 pF

Dead zones:  686-780,  1247-1341, 1808-1887. I can fix that by adding another trimmer or making my steps smaller and use another switch.

So I started working on this and I apologize in advance for the dog-food appearance of the wiring on the back and solder joints. As I get more practice and proper wiring I'm sure I will be able to route the connections better and have a nicer layout and better soldering job. My soldering iron is also one of those pencil-style mini dollar-store pieces of crap and I'm using telephone wire to make the connections.    Anyways, as long as it does the business that's good enough for now.



You can see above the "base" cap in beige, and then the switchable either single blue cap, or the 2 blue-caps (associated with the switches, respectively at the far right edge of the board). My 3 green large trimmers and smaller white trimmer. The easiest way to compensate for the "dead" zones is to add another green trimmer and then take 40 pF off my beige cap (I can use a 68 pF instead of the 151 pF). If I do that, my low end will be 68 (floor)+15(loop)+8(small trimmer)+4x15(green trimmers)=151 pF. My highest end would be 68(floor)+15(loop)+40(small trimmer)+4x160(green trimmers)+1683(both switches on)=2446 pF. So I would improve my range 151 pF - 2446 pF and eliminate the dead zones! 





So once again I whipped out my LCR cheap-o eBay meter and tested it on my PCB and lo-and-behold I was able to tune in various ranges, from a low of about 216 pF to a high of about 2342 pF as you can see in the following photos:





So I went ahead and tried searching for some signals in the LW tuning range of my Tecsun, which was 153 -513 kHz. Unfortunately all that work for next to nothing!  There is not much activity in my area it seems, or at least I can't seem to find it. The loop antenna did help, I was able to find some signals but mostly just beeps and buzzes and strange noises. I found what I thought was MORSE CODE beeping at around 400-405 kHz and I tried to decode it:

- - . . / - / - - - / _______

Dash Dash Dot Dot (Space)  Dash  (Space)  Dash Dash Dash (Space) ... a very very long Dash ......  repeats!

I figured out it was morse code for "ZTO" and probably some kind of radio beacon. I don't know what the long beep at the end is, but probably to indicate end of the message, start again. I did a Google search for ZTO and it turns out it was listed on http://dxinfocentre.com/ndb.htm with the following information:

ZTO  Frequency: 403 kHz
CAN, ON, Toronto - Woodhill
Power: 50
Coordinates: 43°44'18", -79°42'11"

So back on Google maps I went and look what I found!!!!!





That must be what I was listening to! I'm only about 20 minutes drive away, about 20 km or so but barely could make it out on my radio (lots of static and was playing with the tuning). So far I'm not too impressed with the LW aspect of the radio. Seems like nothing interesting is coming in and I while I had fun doing it and learning, it was a lot of work building that antenna and tuner just to pick out a radio beacon 20 km away (and I had to turn my antenna to point to it also). 

Any ideas as to the state of LW signals in Toronto? Is that range fairly dead or am I just not having any luck with reception?

[Lord of nothing]

Hi
I still looking for a good SW Radio for me at home.
But sadly I could not found any who support:
- DRM Radio or even a 10.100khz SSB Output
- NFM on CB Channels

[james_s]

Most of what you'll find in that range are NDBs https://en.wikipedia.org/wiki/Non-directional_beacon

Canadian NDBs have a steady tone during the interval and US NDBs have a gap. Most aircraft navigation uses other means these days but a bunch of the beacons are still around.

[edy]

Most of what you'll find in that range are NDBs https://en.wikipedia.org/wiki/Non-directional_beacon

Canadian NDBs have a steady tone during the interval and US NDBs have a gap. Most aircraft navigation uses other means these days but a bunch of the beacons are still around.

I picked up 3 NBD's so far... the furthest is 47 km away. They are ZTO, ZLP and OO. About 50 W transmitting power each as follows (according to the dxinfocentre site):

403 kHz, ZTO, CAN, ON, Toronto - Woodhill, Power: 50, 43°44'18", -79°42'11" (21 km away)
341 kHz, ZLP, CAN, ON, Toronto - Meadowvale, Power: 40, 43°37'40", -79°43'52" (30 km away)
391 kHz, OO, CAN, ON, Toronto - Oshawa, Power: 50, 43°55'15",-78°54'1" (47 km away)

They are barely audible but enough to pick up morse code and I can decode it. Lots of static but I get better reception turning antenna (very directional). Should I be getting stronger signals or is my antenna just too piss-poor to do the job?  Other than that haven't found anything else interesting yet. Although with the SW mode I've been able to pick up Cuba (11760), Madagascar (11610 Chinese), Romania interfering with Algeria (7375) and I think even Greece (9420).... but I am just using the wire. Next I want to build the MAGLOOP out of coax and see if that improves reception. 

[edy]

I just turned on the radio around 11pm Eastern Time and hit the ETM auto-programming button. After scanning the 2300-21950 kHz range it picked up 2 to 3 dozen stations! Basically the airwaves lit up like a Christmas tree!!!    However, upon closer inspection I tuned through all the channels and it was actually the same program, in various states of clarity, with many frequencies seeming to be overlapping other stations in the background!        Did my Tecsun have a stroke? Or was one of those religious stations (I believe it was WBCQ out of Monticello, Maine) spamming the entire spectrum and on top of almost every other station out there. I could hear nothing else but this ominous symphonic music!

Is this something that you've seen before, or was I having a strange glitch on my radio? After I scanned again I still had this happening although it seems to have subsided somewhat after 11pm. Here are all the frequencies on which I was tuning and hear the exact same music and lady talking about religious stuff:

3150
3170
3205
3215
3330  (on top of the time signal in Canada... could hear it in the background)
3410
3880
4050
4840
5040
5085
5830
5850
5890
5910
5920
5935
6000
6030
6090
6105
6125
6280
7505
9205
9265
9390
9455
11670
11700
13575
13820
15085
15220
15240
15265
15330
15435
15445
17650
17800
21675
21875

       Was this some kind of Shortwave Armageddon?     I couldn't hear any other station without this one on top of it. And there were probably a dozen other stations on the air that were faintly heard in the background. If this really happened (and not a glitch in my radio) how did it overlap all these stations by accident? And if it is a glitch in my radio, why this particular channel?

[bob91343]

Intermodulation could cause this.  The offending station is very close and very strong and is modulating every signal you receive.

That's why some radios include an rf attenuator, to reduce these very strong signals sufficiently to abate the problem.

[james_s]

I pulled out one of my radios several times over the last week or so and I've hardly been able to pick up any NDBs, usually I can hear at least 3 or 4 of them. I think atmospheric conditions are just not favorable right now for that band. Either that or they've decomissioned the beacons.

[vwestlife]

Any ideas as to the state of LW signals in Toronto? Is that range fairly dead or am I just not having any luck with reception?

Longwave has never been used for broadcasting in North America, unlike Europe, Asia, and Africa. During the Cold War the U.S. government had plans to set up a network of longwave stations to broadcast warnings about incoming nuclear attacks to the public, but only one transmitter got built, and (luckily!) all it ever did was transmit time announcements: https://en.wikipedia.org/wiki/WGU-20

But in the Very Low Frequency (VLF) range, you can pick up the signals from military transmitters communicating with submarines, using only a long piece of wire connected to your sound card's microphone input!

[edy]

That video was very interesting. I need to start downloading some of that software and get myself a SDR dongle. Meanwhile, I've been continuing to refine my antenna. I managed to add another trim pot so now I've got overlap between my capacitance "tuning" range and my steps (that I toggle using switches). Before my trimmers only gave me about 40-400 uF range, but I would be able to switch in groups of capacitors that jumped me 500, 1000, 1500 uF. As you can see, I would have a few "dead" spots because I couldn't fully tune up to the next range. I added another trimmer and now it is broader (50-600 uF range) than the steps, so I can actually overlap some regions with different settings (e.g. trimmers tuned all the way up, with no step, or trimmers tuned all the way down, with first step switched on will cover the same range which overlaps by about 50 uF).

The other thing I did was added some wire "taps" to my loop at different numbers of turns. For example, at 1, 2, 3, 4, 6, 10 and 20 turns (and my full loop is 42 turns). Because of this, I have different inductances in my loop depending on which wire I hook into my capacitor-tuner. I made the calculations and printed up a table so I am now covering a large range of frequencies that should be able to resonate in my antenna depending on the "tap" I use, and the range of capacitance I tune in with my trimmer-cap/switch board. I've tried it and I feel that I do get some improvement with certain stations, but then I try my clip-on simple wire (strung across to the end of the backyard through my window) and get decent reception from that too without any fidgeting of capacitors and swapping of tap wires.    However I know the antenna is doing something because I can hear the difference when I turn my trimmers or when I rotate as it is directional.

The other thing I noticed that I may have mentioned previously is that the ETM function (Easy Tuning Mode) on the Tecsun is not picking up every station. It misses quite a few even moderately stations, definitely skips weak ones. I have built up a list and also slowly manually scanned through the frequency range and find other stations that I now dial into and find weak but obvious signals for, which ETM completely misses. For example, even 5000, 10000 and 15000 are clock signals which I pick up. Sometimes I'll find some HAM AM transmissions on 3885, and there are various other spots I've noticed signals that are weak but discernable. So while ETM is great at the beginning, once I am familiar with a few stations I should be able to dial them in and find them. There are also station lists that I am downloading from a DXing digest/forum that I've signed up for, so I am getting reports daily from others.

Now I had the idea when the weather improves to fly up an antenna on a kite... I can just let out 100 foot easily and as long as the weight is not too great and the wind is good, it should hopefully pull up my wire along with the kite string and give me a big antenna. Has anyone tried flying up a wire antenna on a kite? Is there any advantage or more trouble than it helps?

[Bud]

Has anyone tried flying up a wire antenna on a kite? Is there any advantage or more trouble than it helps?

Marconi did, 120 years ago    Guess it gave him some advantage.

[bsfeechannel]

Any ideas as to the state of LW signals in Toronto? Is that range fairly dead or am I just not having any luck with reception?

Longwave has never been used for broadcasting in North America, unlike Europe, Asia, and Africa. During the Cold War the U.S. government had plans to set up a network of longwave stations to broadcast warnings about incoming nuclear attacks to the public, but only one transmitter got built, and (luckily!) all it ever did was transmit time announcements: https://en.wikipedia.org/wiki/WGU-20

But in the Very Low Frequency (VLF) range, you can pick up the signals from military transmitters communicating with submarines, using only a long piece of wire connected to your sound card's microphone input!

Amazing. The Tubular Bells VLF interference is quite a revelation to me. It reminded me of this scene



Very interesting channel by the way.

[edy]

I finally got around to making a video of my Tecsun this morning and I think I picked up India on 11560 kHz! Is it really coming from that far away (I'm in Toronto),  or am I being duped by a closer station or a repeater of some kind? Hopefully I'll have time to make a video of my loop antenna build in the upcoming weeks.  I'm itching to work on more antennas but just didn't have any time.

[fourfathom]

I finally got around to making a video of my Tecsun this morning and I think I picked up India on 11560 kHz! Is it really coming from that far away (I'm in Toronto),  or am I being duped by a closer station or a repeater of some kind?

There's no reason to think that you weren't directly receiving the India station.  When the conditions are right ham operators can talk to the other side of the planet (and sometimes further, via the long path), and they can do it with 100 Watts (or even 10 Watts), and using receivers that aren't any more sensitive than the Tecsun.

I'm glad you're hanging in there! 

[Lord of nothing]

The Indian have a good Digital Radio. Hopefully when I can mount the Antenna Outside I get the with more power. Sadly the fad out often.
You can try out Radio Romania to.

[edy]

You may well have received India but it's worth listening for a while as many stations are repeated and the repeater may throw in a station ident which gives the game away.

You can also google the frequency and station name to find the location of the transmitter.

It was fairly choppy as you can hear in the video, and since then I haven't been able to receive that signal. I guess I need to wait until the proper time of day and conditions. I will try to listen longer to some stations to see if I can make out any repeater ID specs. I did use a site called www.short-wave.info to ID the station. I need to work on a better antenna.

There's no reason to think that you weren't directly receiving the India station.  When the conditions are right ham operators can talk to the other side of the planet (and sometimes further, via the long path), and they can do it with 100 Watts (or even 10 Watts), and using receivers that aren't any more sensitive than the Tecsun.

I'm glad you're hanging in there! 

The conditions must have been just right because I didn't receive anything on that frequency before (at least using the auto-tune search function) and haven't since. I also don't typically listen at that time of day... so I may try tuning in again during the mornings and seeing if I get it again. The auto-tune does miss a lot of stations so I find myself also finding stuff using DXing logs (I am subscribed to one for my local area) and just sometimes manually scanning each frequency. I've picked up radio Romania and also Greece... but Europe is a lot closer than India! Once I picked up Chinese but it happened to be a repeat out of Cuba! That's why I was skeptical.

Using manual tuning I stumbled upon fairly regular HAM shortwave AM activity which I can make out on 3885 kHz (and around there). The auto-tune search completely missed it. I haven't been able to figure out where they are though. They are audible and it is not using any SSB. Part of my limitation is I have a non-SSB capable radio, and I believe there is a lot of activity using weaker signals on SSB. I definitely need to work on my antenna options!

[ADDED:]

I've included a couple of PDF's provided by my local group which gives listening guides by country and English broadcasts.

[bob91343]

You have found the AM nets on 75 meters.  Here in Southern California there are AM nets on Monday and Wednesday around 8PM Pacific time on 3870 kHz.  There are some on 40 meters also but I haven't listened; I think above 7200 kHz.

Check out the SDR on the web; try first KFS.  They offer great radios you can tune from your keyboard and listen to many modes.  You select the frequency.  I think KFS is near San Francisco bay.  There is one in Arizona, and a few others.  You only need a computer, not a radio or antenna.  The display is selectable also.

http://69.27.184.62:8901/
http://websdr1.utahsdr.org:8901/
http://www.i1wqrlinkradio.com/antype/ch121/chiave77.htm

[vk6zgo]

You may well have received India but it's worth listening for a while as many stations are repeated and the repeater may throw in a station ident which gives the game away.

You can also google the frequency and station name to find the location of the transmitter.

It was fairly choppy as you can hear in the video, and since then I haven't been able to receive that signal. I guess I need to wait until the proper time of day and conditions. I will try to listen longer to some stations to see if I can make out any repeater ID specs. I did use a site called www.short-wave.info to ID the station. I need to work on a better antenna.

There's no reason to think that you weren't directly receiving the India station.  When the conditions are right ham operators can talk to the other side of the planet (and sometimes further, via the long path), and they can do it with 100 Watts (or even 10 Watts), and using receivers that aren't any more sensitive than the Tecsun.

I'm glad you're hanging in there! 

The conditions must have been just right because I didn't receive anything on that frequency before (at least using the auto-tune search function) and haven't since. I also don't typically listen at that time of day... so I may try tuning in again during the mornings and seeing if I get it again. The auto-tune does miss a lot of stations so I find myself also finding stuff using DXing logs (I am subscribed to one for my local area) and just sometimes manually scanning each frequency. I've picked up radio Romania and also Greece... but Europe is a lot closer than India! Once I picked up Chinese but it happened to be a repeat out of Cuba! That's why I was skeptical.

Using manual tuning I stumbled upon fairly regular HAM shortwave AM activity which I can make out on 3885 kHz (and around there). The auto-tune search completely missed it. I haven't been able to figure out where they are though. They are audible and it is not using any SSB. Part of my limitation is I have a non-SSB capable radio, and I believe there is a lot of activity using weaker signals on SSB. I definitely need to work on my antenna options!

[ADDED:]

I've included a couple of PDF's provided by my local group which gives listening guides by country and English broadcasts.

For your information:-
The slang term for Amateur Radio Operator is written either with a leading upper case letter ("Ham"), or in all lower case, ("ham").
It is not an acronym, so is not writen as "HAM".

[edy]

I was on late last night ~2 am and found some strange signal of what sounded like a lady speaking numbers in Spanish on 9330 kHz followed by fax/modem noise!!!!! First time I've ever encountered this! I started looking it up on the web searching for "spanish lady numbers" and WOW! This is basically what I was hearing on my radio:



Now, I have no idea how to decode the fax/modem noise. Is it possible to record it on an iPhone and run it through some software? Should I try recording straight to the computer? I doubt that the signal is regular or on the same frequency so chances I will encounter this again are probably slim and definitely will not have the right recording setup available when it happens. Anyways, thought I'd share as it was very strange! Anyone know how to decode this and why the lady says numbers followed by the "noise" (which I assume is some data signal although no idea how it is encoded).... and then repeats this over and over.

[Lord of nothing]

Well you dont want to decode that much since its some Station for Spying and so on. 

[vwestlife]

Now, I have no idea how to decode the fax/modem noise. Is it possible to record it on an iPhone and run it through some software? Should I try recording straight to the computer? I doubt that the signal is regular or on the same frequency so chances I will encounter this again are probably slim and definitely will not have the right recording setup available when it happens. Anyways, thought I'd share as it was very strange! Anyone know how to decode this and why the lady says numbers followed by the "noise" (which I assume is some data signal although no idea how it is encoded).... and then repeats this over and over.

Whatever you could decode would be meaningless anyway, because the data is encrypted.

[edy]

OK I think I figured out it is HM01 and this page lists the schedule which would make sense:

http://priyom.org/number-stations/digital/hm01/schedule

Kind of odd to hear that with today's level of technology this is what spies use? I can't believe it. Must be something else surely!

Wait... I found this article describing number stations. Fascinating!!!!

http://priyom.org/number-stations

[xrunner]

uno dos cinco ocho ocho
seis siete uno dos tres
...

Been going on for decades on the shortwave bands.