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Author Topic: Vietnamese numbers station back to normal, 10255 kHz USB  (Read 2546 times)

Offline Token

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Hello all,

It has been a little while since I reported on the Vietnamese numbers station on 10255 kHz, USB.  Mostly this is because the VTN has been sending nothing but an approximate 1kHz tone for a few months.

To recap, the VTN most commonly sends three identical messages per day starting at about 1600 UTC.  Actual start times vary but typically the first message starts between 1557 and 1603, with 1600 being the most common.  The station was first reported in February of 2010 with a Vietnamese language YL and 5f format.  The message is read by human but recorded on a PC (PC error sounds have been noted in the audio).  From March of 2010 to September of 2010 all messages have been OM, although it was probably not all the same OM.   The station typically sent the same message many days in a row, so that in the period from February of 2010 to September of 2010 only 5 unique messages were actually noted, despite there being well over 100 individual transmissions.

The last numbers transmission I heard from this station was on September 14, 2010.  Starting September 26, 2010 an approximate 1 kHz tone was noted on the frequency starting within seconds of the anticipated start time for the numbers station.  This 1 kHz tone lasted about 5 seconds longer than the anticipated numbers transmission.  From September 26, 2010 to March 6, 2011 this activity continued, with the tone occasionally changing duration, as if the message length had changed.  These changes in length were about as frequent as changes in message length when voice was being sent.  It should be noted that the 1 kHz tone did not contain data, it was a simple 1 kHz tone.  My initial assessment the first few days was that a test tone had been accidently sent instead of the numbers audio.  I still believe that is the most likely case for the entire 6 month period, however I am at a loss to explain how such an error could go on so long and remain unnoticed by the operators.  Possibly there are other frequencies in use, and this is a backup, that might explain why they were so slow in fixing it or why it went so long undetected if that was the case.

On March 7, 2011, numbers again were noted on the frequency in a post to the E2K Group.  This time it was again YL in Vietnamese in 5f format.  I have no recordings of March 3 to March 6, 2011, so I am not sure exactly what day the numbers resumed, when the tone transmissions had gone on for so long I started recording only every few days instead of daily.  Interestingly, on March 8, 2011, the day after the report to E2K of voice, the tone again was sent, again a few seconds longer than the message on March 7 and since March 11.

Since March 11, 2011, the station has transmitted three identical messages each day.  The start time for the first message is about 1600 UTC.  All messages sent since then have been the same 30 group message with the same IDs being sent, each message is identical to all of the others and is apparently a single recording played three times a day.  The current 30 group message length is  about 6 minutes and 16 seconds.

03/11/2011, 10255 kHz USB, 1600:29 UTC 30 grp msg 1, 1607:06 UTC msg 2, 1613:44 UTC msg 3
03/12/2011, 10255 kHz USB, 1600:30 UTC 30 grp msg 1, 1607:08 UTC msg 2, 1613:43 UTC msg 3
03/13/2011, 10255 kHz USB, 1600:32 UTC 30 grp msg 1, 1607:08 UTC msg 2, 1613:44 UTC msg 3
03/14/2011, 10255 kHz USB, 1600:29 UTC 30 grp msg 1, 1607:05 UTC msg 2, 1613:42 UTC msg 3
03/15/2011, 10255 kHz USB, 1600:29 UTC 30 grp msg 1, 1607:05 UTC msg 2, 1613:41 UTC msg 3
03/16/2011, 10255 kHz USB, 1600:27 UTC 30 grp msg 1, 1607:03 UTC msg 2, 1613:39 UTC msg 3
03/17/2011, 10255 kHz USB, 1600:24 UTC 30 grp msg 1, 1607:51 UTC msg 2, 1615:17 UTC msg 3
03/18/2011, 10255 kHz USB, 1600:24 UTC 30 grp msg 1, 1607:49 UTC msg 2, 1615:15 UTC msg 3
03/19/2011, 10255 kHz USB, 1600:23 UTC 30 grp msg 1, 1607:50 UTC msg 2, 1615:15 UTC msg 3
03/20/2011, 10255 kHz USB, 1600:21 UTC 30 grp msg 1, 1607:47 UTC msg 2, 1615:13 UTC msg 3

Iíll get around to updating my web site (http://token_radio.home.mchsi.com/VTN.htm ) of this station shortly, but for now I have a pretty nice recording of the first message of the day on March 16, 2011.  http://www.token.hpathome.net/SharedFiles/VTN_2011_03_16_1600_25_10255USB.mp3

T!
T!
Mojave Desert, California USA

Offline moribund112

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Re: Vietnamese numbers station back to normal, 10255 kHz USB
« Reply #1 on: March 22, 2011, 1119 UTC »
Thanks for all your work Token, I for one am always happy to see updates from you on the various numbers stations.
I'll try listening for this from my location - I'm several hours away from Vietnam by car - so it should be a rather strong signal, shouldn't it?

Offline sat_dxer

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Re: Vietnamese numbers station back to normal, 10255 kHz USB
« Reply #2 on: March 28, 2011, 1651 UTC »
Anyone hear this on Sunday, March 27 from 1600 to 1621UT?


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« Last Edit: May 11, 2014, 1935 UTC by sat_dxer »
Most times & frequencies posted are only an approximation.

Offline sat_dxer

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Re: Vietnamese numbers station back to normal, 10255 kHz USB
« Reply #3 on: April 09, 2011, 1621 UTC »
Activity noted today @ 1600 to 1621UT


« Last Edit: May 11, 2014, 1935 UTC by sat_dxer »
Most times & frequencies posted are only an approximation.

 


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