HFU HF Underground

Loggings => Utility => Topic started by: Guido on December 15, 2016, 2318 UTC

Title: unknown STANAG4285 clear text
Post by: Guido on December 15, 2016, 2318 UTC

Just logged on 8735.8 kHz a STANAG 4285 signal in mode 2400 long.
I did not expect to get some clear text, but I was surprised when decoding with ASCII 8N1 !  (see picture)

Does anybody know who might be on this frequency or who is sending these number groups ?
(Remarkable is the start of the message with "A1B2C3D4E5F6G7H8I9J0")

 

Title: Re: unknown STANAG4285 clear text
Post by: Josh on December 16, 2016, 1524 UTC

Nice catch, will have to start looking more closely at the 2400 and 1200bd sigs.

Title: Re: unknown STANAG4285 clear text
Post by: Guido on December 25, 2016, 2152 UTC

Same Stanag is transmitting on same frequency again just at the moment.
I think I can identify it as a transmission of the Indian Navy:
From time to time I got "VTH DE GOLF UNIFORM" - VTH is listed as Indian navy in Mumbay.
Nevertheless this call and the number groups are quite rare, most of the time I don't see clear text when decoding with ASCII 8N1 framing.

Title: Re: unknown STANAG4285 clear text
Post by: Guido on December 25, 2016, 2213 UTC

Indian Navy just confirmed by this received weather report. (Port Blair on Andamanen near India)
I guess there is more clear text to be received, but a 100% decoding of a 2400bd signal from India over Twente SDR is difficult..