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Author Topic: 502 KHz UNID?  (Read 536 times)

Offline DeepBlue

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502 KHz UNID?
« on: November 09, 2022, 0400 UTC »
Seems to be constantly repeating the same 2 tone type signal approx 10 sec duration over and over. I can't seem to find much if anything on 502KHz stations.  This is not CW. Maybe some new format for beacons I am not familiar with?

Hearing it at S7 in central Ohio, SRRPlay RSP2pro and RF Systems DX10 active antenna, 0358 Nov 9, 2022


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Offline ~SIGINT~

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Re: 502 KHz UNID?
« Reply #1 on: November 10, 2022, 0132 UTC »
Have you tried 518 kHz? That is an international NAVTEX frequency (shore to ship). It's narrow, only about 40 kHz wide, but if you are using a wide filter on the receiver you might be picking it up.


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