HFU HF Underground

Loggings => HF Mystery Signals => Topic started by: KA8BRK on August 08, 2024, 1440 UTC

Title: 28189.500 USB Digital Signal
Post by: KA8BRK on August 08, 2024, 1440 UTC
I have been hearing this digital signal on 28189.500 USB for more than a week now.  It is about S4 - S7 right now.  And, no other signals are being heard on 10 meters.  Also hearing it on several websdr / kiwisdr in west central Ohio.  So, I don't believe it is local.  Also, it exhibits some QSB, further evidence it is not local.  Any one have any idea of the purpose or source of this signal?
KA8BRK
Title: Re: 28189.500 USB Digital Signal
Post by: UtilitySeattle on August 09, 2024, 0002 UTC
In ham band. Could you provide a recording?
Title: Re: 28189.500 USB Digital Signal
Post by: KA8BRK on August 09, 2024, 1324 UTC
Yes, in ham band.  I am not hearing it this morning.
If I hear it again, I will record and post it.
KA8BRK
Title: Re: 28189.500 USB Digital Signal
Post by: KA8BRK on August 15, 2024, 2346 UTC
Unknown signal on 28189.500 USB is back.  Strong signal about S7 or so on the 706 using a 140 foot inverted vee to receive.
Also, decent signal using the kiwisdr at W8RKO, (nippynet.org:8073).
I have .wav files, no way to post.
KA8BRK
Title: Re: 28189.500 USB Digital Signal
Post by: UtilitySeattle on August 16, 2024, 0836 UTC
You can upload to https://vocaroo.com/ and share the link with us.
Title: Re: 28189.500 USB Digital Signal
Post by: KA8BRK on August 16, 2024, 1634 UTC

30 second .wav file at:  https://voca.ro/1eOKM3cP1pI0
2 screenshots at:  https://imgur.com/a/fYd6enP
The first was taken after several minutes of monitoring with WSPR.
The FT8 signal is n4wlo calling w4wlo or maybe vice-versa.
The second is from the kiwisdr at w8rko (nippynet.com:8073).
KA8BRK
Title: Re: 28189.500 USB Digital Signal
Post by: UtilitySeattle on August 16, 2024, 2332 UTC
You can look here for audio samples:

https://www.sigidwiki.com/wiki/Signal_Identification_Guide (https://www.sigidwiki.com/wiki/Signal_Identification_Guide)

I think it might be FDMDV:

https://www.sigidwiki.com/wiki/Frequency_Division_Multiplex_Digital_Voice_(FDMDV) (https://www.sigidwiki.com/wiki/Frequency_Division_Multiplex_Digital_Voice_(FDMDV))