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Loggings => HF Mystery Signals => Topic started by: Ramonthebiker on May 07, 2019, 2013 UTC

Title: frequency hopping set of repeating pulses
Post by: Ramonthebiker on May 07, 2019, 2013 UTC
Looking around 80m on my SDR I saw what looks to be a beacon of some sort and I wonder if anyone can confirm?

It seemed to start as a short pulse at 3,310khz then repeats 10 or 20khz higher before repeating the whole pattern approx 700khz higher a few seconds later, and a weaker repeat 780khz higher 5 seconds after that.

I am near Oxford and a contact of mine up in the North of England can also see this signal sequence - the waterfall pattern looks like this:

         I
        II
       II
       I
     
Any idea?

73, Ramon
Title: Re: frequency hopping set of repeating pulses
Post by: Token on May 09, 2019, 0109 UTC
Let me preface with, I am not sure, but I suspect:

This looks like it may be STANAG 4539 out of UK DHFCS.  This should be sequencing, frequency hopping, through 20 channels.  In sequence: 2082, 2088, 2097, 2501, 2688, 3312, 3318, 3327, 4022, 4028, 4037, 4782, 4788, 4797, 5742, 5748, 5757, 7807, 7813, and 7822 kHz.

T!