HFU HF Underground

Loggings => HF Mystery Signals => Topic started by: alleycat on March 30, 2021, 0143 UTC

Title: Amateur mode 7040kHz PSK variant?
Post by: alleycat 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 (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 (https://www.lutins.org/temp/radio/7040_digi.mp3) waterfall as shown below. Thanks for any assistance!
(https://www.lutins.org/temp/radio/7040_digi.jpg)