HFU HF Underground

Loggings => Other => Topic started by: Capt. Radio on December 02, 2013, 2258 UTC

Title: UNID digital sounding QRM 6955-85 2250u
Post by: Capt. Radio on December 02, 2013, 2258 UTC

Hearing powerful "interference", wideband roughly 6955-6985khz at S-5 to S-7 signals... sounds digital. really wipes out everything between those freqs here in Indiana. Not steady, comes and goes.

Maybe that same signal that was reported on 5140 a few posts earlier but has moved up in freq?

Title: Re: UNID digital sounding QRM 6955-85 2250u
Post by: ChrisSmolinski on December 03, 2013, 1230 UTC

Noted here on the SDR recording, and I have noticed it many times in the past.  I believe this is MIL-188-110C.

I found some information about it here: http://www.hfindustry.com/meetings_presentations/presentation_materials/2011_jan_hfia/presentations/11_GREGORY_110CAppDDigitalVoiceDataRates.pdf
and here: http://www.shoc.ch/protocols/articles/mil-std-188-110c-appd.html