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RadioReference.com Forums
Stumbled on this doing a slow band scan. Thought at first it was an image of a strong AM broadcaster but I looked at the audio waterfall then listened and decided thatss a weird one. Did some searching on google and found it is STANAG 4285 PSK or JET XJT. could be USA or New Zealand. No clear information.
I didn't bother trying to decode it. All it will be is encryption anyway.