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Author Topic: Vietnamese numbers station, TX changes, September and early October, 2010  (Read 1778 times)

Offline Token

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It has been a while since I have reported on the Vietnamese numbers station (10255 kHz, USB, OM, Vietnamese, 5f).  That is because while I have been recording it on a daily basis I have not looked at the recordings in over a month, I simply have not had the time.  And when I did look at them yesterday I saw some odd activity.

My last report included up to August 31, 2010, so I will pick up on September 1, 2010.

From September 1, 2010, until September 14, 2010 the station did just what it has done for months.  It sent the same 42 group message it had been sending since April 22, 2010, this message is 3 minutes and 29 seconds long.  It sent three messages a day with the same timing trends it had been using for months.

September 14, 2010, was the last numbers transmission I heard from this station.

From September 15 to September 25, 2010, no transmissions were heard at my location.  This 11 day gap is by far the longest I have seen since I started watching this station, the previous longest period of no reception was 3 days.

Starting on September 26, 2010, and right on scheduled time for the numbers to start, a tone was heard.  This tone was a steady 970 Hz with no information on it at all, just a steady tone.  The tone lasted 6 seconds longer than the 42 group message would have.  At approximately the time the second 42 group message of the day would have started the tone again started, and it ran 6 seconds longer than the 42 group message would have been.  At about the time the third and final 42 group message of the day would have started the tone again started, and it lasted 8 seconds longer than the 42 group message would have.

From then through October 5, 2010, if any transmission was seen it was the tone, and the tone closely mimicked the habits of the 42 group messages.  The 42 group messages are either 3 minutes and 29 seconds, or 3 minutes and 30 seconds long, depending on when the second hand of the clock falls.  The tones were between 3 minutes and 35 seconds and 3 minutes and 38 seconds long.  As if the transmitter would have been turned on a couple of seconds before, and turned off a couple of seconds after, the 42 group message audio would have been sent.

On October 6, 2010, the tone durations reduced to between 2 minutes and 29 seconds to 2 minutes and 31 seconds in length.  All other habits remained the same. Still about the same spacing and still three transmissions a day.  This lasted for 3 days worth of transmissions.

Today, October 11, 2010, the tone duration increased, going to about 3 minutes and 45 seconds in length.  As I only have one days worth of samples, today’s three transmissions, I do not know if this is going to be the average or not.  All other actions remained the same, three transmissions, and about the same gaps between transmissions.

Tones of 950, 970, and 985 Hz have been observed on different days, but the tone is steady through a given day.  This might be a transmitter settling on a slightly different freq from day to day.

It is my opinion that the tones are being sent instead of the numbers transmission.  As the tone is steady and contains no information I believe this might be a failure or operator error.

Further, the change in timing on October 6 and again on October 11 might indicate that a different message is being sent, or at least would be being sent if the audio were present.

T!
Mohave Desert, California, USA

My logs, September 1, 2010, to October 11, 2010.  (complete trends can be seen on my VTN web page, http://token_radio.home.mchsi.com/VTN.htm )

September, 2010

- 09/01/2010  1557:30 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1602:07, 3rd msg start 1606:44
- 09/02/2010  No transmission heard</p>
- 09/03/2010  1557:29 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1602:07, 3rd msg start 1606:43
- 09/04/2010  1557:31 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1602:08, 3rd msg start 1606:46
- 09/05/2010  1557:30 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1603:07, 3rd msg start 1608:44
- 09/06/2010  1557:28 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1603:05, 3rd msg start 1608:41
- 09/07/2010  1557:27 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1603:04, 3rd msg start 1608:41
- 09/08/2010  No transmission heard
- 09/09/2010  No transmission heard
- 09/10/2010  No transmission heard
- 09/11/2010  1557:22 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1602:59, 3rd msg start 1608:36
- 09/12/2010  1557:21 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1602:57, 3rd msg start 1608:34
- 09/13/2010  1557:19 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1602:56, 3rd msg start 1608:33
- 09/14/2010  1557:18 UTC first msg, 42 grps, VT, OM, 5f, 2nd msg start 1602:55, 3rd msg start 1608:34
- 09/15/2010  No transmission heard
- 09/16/2010  No transmission heard
- 09/17/2010  No transmission heard
- 09/18/2010  No transmission heard
- 09/19/2010  No transmission heard
- 09/20/2010  No transmission heard
- 09/21/2010  No transmission heard
- 09/22/2010  No transmission heard
- 09/23/2010  No transmission heard
- 09/24/2010  No transmission heard
- 09/25/2010  No transmission heard
- 09/26/2010  No numbers heard, Tone, 970 Hz, 1557:05 – 1600:40 UTC, 1601:40 – 1605:17 UTC, 1606:17 – 1609:54 UTC
- 09/27/2010  No numbers heard, Tone, 970 Hz, 1557:06 – 1600:41 UTC, 1602:13 – 1605:49 UTC, 1607:20 – 1610:56 UTC
- 09/28/2010  No numbers heard, Tone, 970 Hz, 1557:04 – 1600:39 UTC, 1602:11 – 1605:47 UTC,   1607:18 – 1610:52 UTC
- 09/29/2010  No numbers heard, Tone, 970 Hz, 1557:04 – 1600:39 UTC, 1602:12 – 1605:46 UTC,   1607:18 – 1610:54 UTC
- 09/30/2010  No transmission heard

October, 2010

- 10/01/2010  No numbers heard, Tone, 985 Hz, 1557:02 – 1600:37 UTC, 1602:09 – 1605:44 UTC,   1607:15 – 1610:51 UTC
- 10/02/2010  No transmission heard
- 10/03/2010  No transmission heard
- 10/04/2010  No transmission heard
- 10/05/2010  No numbers heard, Tone, 950 Hz, 1557:02 – 1600:37 UTC, 1602:37 – 1606:14 UTC, 1608:14 – 1611:52 UTC
- 10/06/2010  No numbers heard, Tone, 950 Hz, 1556:58 – 1559:28 UTC, 1600:29 – 1602:59 UTC, 1604:01 – 1606:30 UTC
- 10/07/2010  No numbers heard, Tone, 950 Hz, 1556:58 – 1559:28 UTC, 1600:29 – 1602:59 UTC, 1604:00 – 1606:29 UTC
- 10/08/2010  No numbers heard, Tone, 970 Hz, 1556:56 – 1559:25 UTC, 1600:27 – 1602:56 UTC, 1603:57 – 1606:26 UTC
- 10/09/2010  No transmission heard
- 10/10/2010  No numbers heard, Tone, 970 Hz, 1556:52 – 1559:24 UTC, 1601:24 – 1603:55 UTC, 1605:56 – 1608:26 UTC
- 10/11/2010  No numbers heard, Tone, 970 Hz, 1556:51 – 1600:39 UTC, 1602:38 – 1606:23 UTC, 1608:25 – 1612:10 UTC
T!
Mojave Desert, California USA

Offline Sealord

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Helluva report Token - thnx!

I've had no luck hearing any of the asian services here in Fl., but still try off & on :)
Indoors: WR-G33DDC & TT RX-340_DX Eng. 4-Square Array / Outdoors: Belka-DX_Whip / Poolside: SMC HF-150_MMD-40 (D.O.G.) / Off Air/Studio Recordings