"Akura" ("Shark") aka Щука

[FWBStEUSchw]

Kann jemand mit diesem Modem etwas anfangen bzw. hat weitere Infos dazu?

73 Tom

Screenshot: https://1drv.ms/u/s!ArVninh21A3Cgv0Kq_U5qw5C9v0CtA?e=M045Y2
Audio (WAV): https://1drv.ms/u/s!ArVninh21A3Cgv0LLolYPuGggjoZug?e=oVuuHw

[FWBStEUSchw]

Oh sorry, I've asked "Can anyone do anything with this modem or have further information about it?" Meanwhile I'vo got the note that this is "Akula" (russ.), i.e. "Shark" in Englisch. More infos at

https://i56578-swl.blogspot.com/2015/07/cis-navy-shark-akula.html

[Josh]

Hallo und danke fur das sovieten uboot signalen.

This is classic fsk Akula, sometimes they send a burst of bpsk prior to the fsk, missing in this instance, and from your screen grab has a cf of 7116, nicely in the digital portion of the 40m HAM band lol. A date and time to go along with the catch?

Most likely source will be Russian subs followed by Russian navy surface asset recon reports, regardless of source Akula use is the highest priority hf traffic as far as Russian Navy HQ is concerned. Dunno about the surface ships output power but the subs can send on hf with substantial power, tens of kw. 20kw or more to a floating or even near surface long wire hf antenna can be heard around the world if conditions are right, if surfaced and using a vertical it'd be hard not to hear them. I feel Antonio has compiled the most open source info on the mode so far and has some info on the 30khz wide psk version of Akula;
http://i56578-swl.blogspot.com/search/label/Akula