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Author Topic: M94 S. Korean Morse Numbers Transmission on 6330 KHz  (Read 7225 times)

Offline 4405486

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M94 S. Korean Morse Numbers Transmission on 6330 KHz
« on: October 10, 2010, 1820 UTC »
Here San Luis Obispo, California I have: M94  1400 - 1406 UTC  OCT. 10 2010 very weak signal through noise, could only copy bits and pieces. My best guess is that this is the first transmission of two. Hopefully will be a repeat transmission tomorrow at 1400 UTC. Main Page of this site has excellent article M94 with typical format. Article lists 4500, 5115, 5715 KHz as the frequencies; maybe, 6330 KHz should be included? at least for now, could all change after first of the new year. Main page Articles concerning Number Stations and what not, gets better and better. Cheers.

Offline Token

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #1 on: October 10, 2010, 1931 UTC »
Sorry, I have been meaning to update the V24 and M94 pages for some time now, both here and my own pages.  I also have a good and current schedule worked out.

The only freqs still in use by either V24 or M94 are 5715, 6215, 6330, and 6730.  V24 uses all four of those freqs but M94 only uses two of them, 5715 and 6330.  The 6330 freq was added to both the V24 and M94 line-up in either January or early February of 2010.

This mornings M94 you heard used ID 815.  Also, did you notice the audio drop outs that plagued the transmission?  The later V24 transmissions had even bigger audio drops.  Both of these stations do this occasiaonally, eventually the ops will fix the loose connection and all will be back to normal.

Tomorrow morning M94 will transmit again in the same time slot and frequency.

EDIT:  M94 page here updated to include 6330 and the fact that only 5715 and 6330 are currently in use by M94.
« Last Edit: October 10, 2010, 2000 UTC by Token »
T!
Mojave Desert, California USA

Offline 4405486

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #2 on: October 10, 2010, 2043 UTC »
No Problems, your beyond reproach- work is excellent. I had listed M94 on 6330 KHz some time ago elsewhere, and was wondering why this wasn't verifying- is now. Same Group I had listed tail end of CW transmission on a frequency that had once been used by Korea only it was North Korea! I might want to take that listing back!

I have noticed your YouTube Videos- Keywords: V24, M94, V13, V26, Chinese Robot... I Highly recommend; very well done. Also I have noticed the Video- Keywords: Secret numbers stations from film Der Westen Leuchet. Same Video is on Simon Masons Site, but seems to take forever to download. Particular Video is Somewhat creepy; however, is a good example of One-Time Encryption. Cheers.

Offline 4405486

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #3 on: October 11, 2010, 1751 UTC »
Briefly, in passing; Repeat transmission observed this morning. Unuseable signal some Morse copyed near end of transmission. Carrier was clearly delineated well before start time. Useing inexpensive compact portable with whip antenna. At times M94 is solid enough for good Code Copying Practice- even with the Rig I have. Cheers.

Offline Token

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #4 on: October 11, 2010, 2201 UTC »
lol...don't feel so bad.  M94 was having audio problems this morning.  Of the total 7 minute transmission from 1400 to 1407 (carrier was indeed up well before that though, as it normally is) there was about one minute of code sent, and it started very late (about 1404:16) in mid number and dropped out several times in the short part that could be heard (the cw ended in mid number at 1405:11).  There was one addtional dit at 1405:29, and at 1406:05 seven and a half additional numbers were sent, and that was it, the carrier dropped at 1407:00.

In other words, M94 had the problem this morning, probably not you.  If you heard any code at all that was as good as it got.  The signal was 20 over S9 here and I still only got a very short bit of code.  You cannot receive what is not sent.
« Last Edit: October 11, 2010, 2203 UTC by Token »
T!
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Offline 4405486

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #5 on: October 13, 2010, 1835 UTC »
It's all good with me. I don't have the equipment you do; and optimized at that; but I do have fun with it and will get around to doing some building one of these days. I could only copy bits and pieces. Second transmission was worse than the first- K Index was somewhat elevated. Did observe M94 on 5715 kHz About 1400-1408 UTC  this Morning poor, unuseable signal again. Are these transmissions Diplomatic in nature? Maybe South Korean Embassy in Japan? Any information appreciated.

Also, noted your HF-GCS Video with the "Sky King" Preamble on YouTube Very Nice. I placed My HF-GCS Listing In The Spy Numbers section because seems to me some type or variation of One-Time Encryption is being used and I thought Folks interested in Numbers Stations would be the most likely to appreciate. At any rate an extraordinay system. I have an old Article (1959) called: Development Trends in USAF Global Communications Systems. Very technical I think the same as HF-GCS -will have to read and find out for sure.

I've been involved in some extremely rigorous interests and persuits the last several years; have not had that much time and energy left for Radio. Any Verifiable Observation- no matter the equipment, can be valuable- another Data Point, or so it seems to me. Cheers.
« Last Edit: October 13, 2010, 1903 UTC by 4405486 »

Offline Token

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #6 on: October 14, 2010, 0008 UTC »
It's all good with me. I don't have the equipment you do; and optimized at that; but I do have fun with it and will get around to doing some building one of these days. I could only copy bits and pieces. Second transmission was worse than the first- K Index was somewhat elevated. Did observe M94 on 5715 kHz About 1400-1408 UTC  this Morning poor, unuseable signal again. Are these transmissions Diplomatic in nature? Maybe South Korean Embassy in Japan? Any information appreciated.

This mornings M94 on 5715 kHz at 1400 (end time 1408:48) used the ID 1014, vs the ID of 815 used on the 6330 M94 you reported the other day.  This was the second day of this message, an identical message was sent yesterday in the same time slot on the same frequency.  It was not great but still OK in here this morning, at about 10 over S9.  It also had some audio dropouts as the 6330 signal did, although not quite as bad.

Tomorrow the 1400 time slot will be empty on all frequencies.  I believe the only M94/V24 transmissions tomorrow will be V24 at 1530 on 6730.  (EDIT  Ooops, I looked at the wrong line on the chart.  There will actually be several TX's of V24 today and possibly one M94.)

The nature of the signal is, of course, subject to some controversy.  It is highly unlikely it would be "diplomatic" in nature as there are other known links for that, and such communications tend to be two-way.  This type is, by its nature, one way.  The prevailing thought is that these are like many "numbers" transmissions, one-way communications with assets in the field.  Communications that do not in any way reveal the location or identity of the recipient.

V24 and M94 have been RFDF'ed to be originating in South Korea itself.  And it has essentially been confirmed that they originate from the same transmitter.  Since they originate in South Korea but V24 always uses North Korean lead in songs it is assumed that the recipients might be in North Korea.

Also, noted your HF-GCS Video with the "Sky King" Preamble on YouTube Very Nice. I placed My HF-GCS Listing In The Spy Numbers section because seems to me some type or variation of One-Time Encryption is being used and I thought Folks interested in Numbers Stations would be the most likely to appreciate.

There are many transmissions to be found on HF that fit the profile of encoded numbers or letters groups, particularly in CW mode today.  However, Spy Numbers stations are a specific breed.  GHFS is generally not considered a numbers transmission despite the fact that it may be of interest to people also watching numbers stations.  I made sure to specify that in my video just so that new people, possibly trying to find an example to compare to what they are hearing, would know that.

There have been a few people putting GHFS receptions in the Spy Numbers Database, and that can create incorrect data when people are trying to build prediction tables.
« Last Edit: October 14, 2010, 1302 UTC by Token »
T!
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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #7 on: October 14, 2010, 1807 UTC »
TNX VY for information. Nothing observed on 5715 KHz at 1400 UTC; therefore assumed yesterday was second of two transmissions. My reception has been so poor lately that I can't observe these Audio drop outs you describe; periodicaly seem to catch a lucky Hop and can copy a bit of the signal from time to time as it comes out of the noise. I was under the impression from material I had read sometime ago that V24/M94 recipients may be located in Japan- the reasons why escape me; and I don't want to tread on any possible sensitivities. North Korea would be the most logical choice; however, I would expect more jamming that being the case. I don't know about you; but once in a while I have observered a random, momentary "Toot" or some other type of nusance sound from some unknown source during these transmissions; but not full scale jamming. Although; I don't have nearly enough Data Points (take all I can get for V2, M8a, SK01) to draw any conclusions at all on a Equidistant Projection, the few I do have suggest a defined trajectory for M94/V24 as opposed to a omni-directional antenna; However, this is anecdotal at best. I have one V24 observation from Italy that could be explained as coming from the Backlobe of a directional antenna. Again this is just food for thought, fun to speculate- no conclusions can be drawn. For some reason, I keep thinking of 200-250 KW Transmitters with Curtain Array Antennas, but that's just me.

Has V13 changed schedule? Or is it just the propagation? Lately have not observed on 10522 KHz at 1200 and 1300 UTC. Hopefully, conditions improve and I can hear it again. Very Exotic sounding transmission. TNX.
« Last Edit: October 14, 2010, 1845 UTC by 4405486 »

Offline Token

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #8 on: October 14, 2010, 1955 UTC »
Yes, my chart shows nothing at 1400 on any freq today.  And yesterday was the second day for that M94 message at 1400 on 5715 kHz.  I am at work and my chart is not in front of me but from memory today there should have been several V24 transmissions on 6730, one on 6330, and one M94 on 5715.

The thing that might be driving your assumption about V24 and Japan is the fact that prior to me starting to watch it and report it was by far most often reported out of Japan.  Prior to my first reception of V24 at least 90% of all reports came out of Japan.  Someone may have assumed Japan was the target region from that.  Also, a Japanese group of hobbiest published a rather hard look at it in the late 90’s or early 2000’s.

However, I very much doubt Japan is the target region.

Think about the frequency and the time frame.  Korean Standard Time is UTC +9, that means local time for the 1200 – 1630 UTC window would be 2100 – 0330, well into dark.  The freqs used are best during dark hours or shortly after sunup.  This means they propagate best to places that have a dark path from Korea to the receive station.  When you look at that you will see that the best potential paths (disregarding antenna pattern) would be from Korea to the north, south, and east with poor paths to the west until the last part of the time window during the winter. 

Despite this the station has been reported from Europe many times, particularly when the European listeners are queued that the station is on the air at the time or will start in a short time.  It has been reported from Russia even more often.  And when I have listened for it on Australian based remote tuned SW receivers it has come in better there than here.  All of this would tend to weigh against directionality towards Japan.  Europe is simply a tough haul for that signal at that time, even if the antenna was pointed right at Europe intentionally.  And in the other directions there seem to be few numbers listeners until you get to Japan or the US and Canada.

I recently was contacted by a few people that seemed to have the idea that V24 and M94 (and the Vietnamese numbers station also, but that is a different story) were targeted at the US west coast.  When I asked them why they thought that they said because that is where it is most often reported being received so it must be targeting that area.  I explained to them that if one person is making a habit of reporting it often that does not mean that person is in the area it is pointed at, only that one particular person might be making a greater than average effort to hear and report it, skewing the data.

If you remove my reports and any reports from Japan you will see it has only been reported in the US only about twice as often as in Europe, despite Europe having an abysmal path and the west coast of the US having a pretty good one.

Remember the data for M94 might be a bit shallow, we only got that designator assigned in June of last year, despite the fact the station has been on the air for years.  Because so few European listeners can hear M94 it was not until I started reporting it to the Enigma group and clearly defined the habits that they felt comfortable assigning it an ID.

I do not think V13 has changed schedule.  The last time I tuned for it was this past Monday, and it was there at 1300 UTC on 10522 kHz.  I will check it tomorrow morning to make sure.
T!
Mojave Desert, California USA

Offline 4405486

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #9 on: October 15, 2010, 1820 UTC »
Thank You! Very much for the information. Food for thought- will chew on it. Just seems like an excessive amount of power in use for going from South Korea to North Korea; or even to Japan for that matter. Seat of the pants estimate- maybe 100-250 kw Transmitters or so it sounds like to me. I'm somewhat familiar with the sound of Radio South Korea- power levels sound comparable to me; again nothing factual, just a rough guestimate. Information I had read before was from individuals from Japan- if I can find the time May see if I can contact some of them, I have tried before. I like many people zip around the Internet without spending too much time at one location. I'll spend some time and take another look at this. When both North and South Korea were transmitting, I can understand the lack of jamming. My understanding, is that the North does not transmit anymore except on a rare ocassion; hence, they might have more incentive to jam the South- would'nt be out of character for them. Just more speculation on my part. I am pretty open minded, but will defer to hard evidence.


I do think plotting points on a projection or the like is a valid technique and given enough observations from enough locations I would expect patterns and usefull inferences to emerge after taking into account propagation conditions which could tend to temporarily change the typical signal path direction and even enhance or attenuate signal strength. This is a complex process, with a lot of variables, and is frequency dependent. Someone with Antenna and Propagation Modeling could have fun with this. I'm just a Hobbyiest and don't have that kind of expertise- but do find this interesting.

Paul Harden- NA5N wrote a very good 8 page article a couple of years ago: "Solar Acticity & the Solar Physics behind HF Propagation"
Geared towards QRP Operators with Tips on taking advantage of changing conditions. ShortWave Listeners might find it educational.

 RE: V13 Must be my cheap receiver! will try again. Was not having a problem receiving V13 untill recently. Cheers. VY TNX 73 ..
« Last Edit: October 15, 2010, 2053 UTC by 4405486 »

Offline Token

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #10 on: October 16, 2010, 1647 UTC »
Just seems like an excessive amount of power in use for going from South Korea to North Korea; or even to Japan for that matter. Seat of the pants estimate- maybe 100-250 kw Transmitters or so it sounds like to me. I'm somewhat familiar with the sound of Radio South Korea- power levels sound comparable to me; again nothing factual, just a rough guestimate

If your receive target is using a small, inconspicuous, run-of-the-mill portable commercial SW receiver with a whip antenna there is no such thing as too much power.  And if you look in that frequency region you will see many BC transmissions from North and South Korea, aimed at each other or the general region, running powers from 50 to 250 kW.  When the Voice of Hope, The Voice of The People, or KCBS Pyongyang transmits in Korean it is not meant for anyplace else, but those are the power levels they use.

However, one has to be careful with relative or received power levels, they can be very deceiving, especially on HF.  For example, day-to-day variations can make a huge difference, but seasonal variations are even larger.

It is essentially impossible to tell an HF skywave 100 kW station from a 200 kW station using relative spot checks performed at different times, you simply can not pin down a skywave received power on HF to within 3 or 6 dB without some significant effort, they are far too up and down on average.  And 6 dB is the difference between a 200 kW station and a 50 kW station.  When we work in microwave, with direct line of site and practically no propagation variation we generally consider the error of measurement for any single measurement to be +/- 2 dB (unless on an instrumented range), and HF skywave is much worse than that.

This morning I did a direct comparison, for what it is worth.  One of the nice things about an SDR is that it can display a wide range of freqs simultaneously, and record them for review, making simultaneous measurements easy.  Using a 150 kHz bandwidth and starting at 1500 UTC and for the duration of the V24 transmission I recorded both V24 on 6215 kHz and KCBS out of Pyongyang DPRK on 6100 kHz in a single file, from a single antenna, pretty much making all variables on my end identical.  The two stations are close enough in frequency that propagation differences (other than instantaneous) should be negligible.

KCBS Pyongyang is listed with a transmitter power of 125 kW and a non-directional antenna.

V24 on 6215 kHz was peaking at a level of –54 dBm (S9 +19 dB), with occasional fades down 20 to 30 dB from that.  KCBS on 6100 kHz was peaking at about –48 dBm (S9 +25 dB), also with fades 20 or 30 dB down from the peaks.  On average I would say KCBS showed MORE fading than V24, but not deeper fading, and KCBS consistently showed a higher peak.  The signal level differences between these stations were indistinguishable by ear, in fact, if anything, the V24 sounded slightly stronger, with the female voice (KCBS was mostly music and male announcer) punching through better.

On the surface this data would suggest that, disregarding transmit antenna patterns, KCBS is transmitting 6 dB more power than V24.  We know KCBS is at 125 kW.  6 dB down from that would be 31.25 kW.  It would be easy to draw a possible conclusion that if both stations are using non-directional antennas and KCBS is at their published 125 kW, then V24 must be about 30 kW.

However, I would be very leery of making any conclusion from one set of measurements, no matter how hard a person tries to keep it an apples and apples kind of thing.  For example, what if V24 is running 250 kW, but with a directional antenna and I happen to be in a null, a sidelobe, or just on the edge of the main beam, that is 10 dB down?  That would produce pretty much the same results.

Now, if three or more people did the same test, synchronized but from geographically disperse areas, all yielding the same or similar results, then I would start to say V24 was at 25 or 30 kW.  But I am not sure there are three or more people even looking at V24 on a given day.

I do think plotting points on a projection or the like is a valid technique and given enough observations from enough locations I would expect patterns and usefull inferences to emerge after taking into account propagation conditions which could tend to temporarily change the typical signal path direction and even enhance or attenuate signal strength. This is a complex process, with a lot of variables, and is frequency dependent. Someone with Antenna and Propagation Modeling could have fun with this. I'm just a Hobbyiest and don't have that kind of expertise- but do find this interesting.

If you can take the propagation for each individual intercept and the individual receive station variations (such as what receive antenna was used, its orientation, what feedline was used, what was the performance limitation of each receive station) into account then plotting reception to determine a possible radiation pattern might be valid.

Merely saying the signal was received by station X at S7, Y at S5, and Z at 20 over S9, while station R did not receive it at all, or worse yet, no signal levels, just it was received by X, Y, and Z, but not R, tells you nothing, even if you know the locations of each station.  Factoring in the propagation for each specific and individual reception by each station starts to narrow it down, but still leaves the individual receive station performance factors in question.

If you have large enough pool of individual receive stations, and you have reports from those stations on other signals of interest, then maybe performance differences might start to average out and be less important.  You could identify the “flyers”, the stations that are always reporting everything as 40 over S9 could be identified, as could the stations that struggle to hear what should be power house signals.
T!
Mojave Desert, California USA

Offline 4405486

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #11 on: October 16, 2010, 1739 UTC »
More to chew on! Thank you Sir! Pressed for time- will study and digest this when I can get to it. I do agree that relative or perceived power levels can be very deceiving. Iv'e noticed that while listening to the various power levels used by the International Beacon Project; but from 30 kW to 150-200 kW? I guess I'll just accept this. The way Human Hearing works is a factor in this as I recall; as well as, of course seasonal and daily variations in propagation. My Internet use is very limited, as such I don't follow propagation variables closely- It is "seat of the pants" relative guestimates with me. As stated, I'm just a Hobbyiest and do recognize some of the"complexities" and variables involved; as stated someone with Propagation and Antenna modeling expertise could have fun with this. I listened for V13 on 10522 KHz at 1200z and 1300z. For all practicle purposes could not receive; with exception of the briefest moment or two- and this only because I knew what to expect. In terms of equipment, I'm out classed for sure; I'll give most people that. I was curious to see what factors were contributing to this; as I had been receiving V13 fairly well and we are moving into good winter conditions- Grey Line imediately comes to mind, will check into it when have the time.



VY TNX for very interesting and educational Thread 73 KG6QNK ..
« Last Edit: October 16, 2010, 1928 UTC by 4405486 »

Offline 4405486

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Re: M94 S. Korean Morse Numbers Transmission on 6330 KHz
« Reply #12 on: October 17, 2010, 1817 UTC »
This one is getting beat to death; or so it seems to me; however, after pondering the 30 kW power out Token comes up with- that does sound reasonable and conceivable to me. Given the ratios involved and the power that could be expected to be used up in the form of heat and so forth at 150 kW; 30 kW or even less could sound comparable to a 150 kW signal and still get into Texas in the Winter.

I'm useing a somewhat tired compact portable with whip antenna (go all out, and hook up an auxilary length of wire). This Radio has seen heavy use and was what I used for a year as a Deutsche Welle Technical Monitor (I was a Data Point); good enough for them, good enough for me. Unfortunately, sometime back I lost quite a bit in the way of homebuilt Rigs, parts inventory, tools and so forth. While not attempting to put on airs or pretenses (I'm no Wes Hayward); I do have some Marine Corps, Navy, and Air Force Technical Training; some of which is still relevant, to fall back on- good enough for them, good enough for me. In addition, I have passed all the Amateur tests (and play strictly by the rules). Therefore, I feel more than qualifyed to be an Amateur Hobbyiest. I'm gravitating more towards the "simple"; General coverage RCVR and QRP. That having been said, I try to promote and encourage all aspects of Radio. There is a lot to be said for these SDR's with the various types of displays- those so inclined, go there.

 

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