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Author Topic: UNID digital sounding QRM 6955-85 2250u  (Read 1283 times)

Capt. Radio

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UNID digital sounding QRM 6955-85 2250u
« 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?
« Last Edit: December 02, 2013, 2316 UTC by Capt. Radio »

Offline ChrisSmolinski

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Re: UNID digital sounding QRM 6955-85 2250u
« Reply #1 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
Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
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