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HF Mystery Signals / Amateur mode 7040kHz PSK variant?
« on: March 30, 2021, 0143 UTC »
I'm seeing 2-minute long narrowband (roughly 75 Hz wide?) digital QSOs on 7040 kHz that I can't identify (apparently nothing similar at SigIdWiki). I think it might be some variant of PSK based on the resources at http://www.w1hkj.com/modes/index.htm, but I ran through all these modes in MultiPSK to no avail. Audio at https://www.lutins.org/temp/radio/7040_digi.mp3 waterfall as shown below. Thanks for any assistance!
