4021 kHz MARS net heard @ 8:40 to 9:00 am PST (16:40 to 17:00z) on 12/2/21. Received in Portland, Oregon. Fairly good copy on seemingly every participant, as though they’re all in the same general area. California would be my guess, but could be Washington or Idaho. About a dozen stations heard. Occasionally one station would transmit a message to another in a brief digital signal. Signal sounded like perhaps a PSK type such as MIL-STD-188-110 Serial. I don’t see this 4021 frequency listed for MARS in the list I have. It was mentioned during the net that it’s a new frequency for them as of 2021.
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