Thanks for the reply, seems like “open COM4 and start reading, decoding as per the protocol” is the way to go.

anyone interested in this, take a look at “Capturing AIS NMEA messages from Quark Elec QK A021 AIS Receiver USB dongle” https://github.com/freerange/ais-on-sdr/wiki/Capturing-AIS-NMEA-messages-from-Quark-Elec-QK-A021-AIS-Receiver-USB-dongle

And verify your decoding against this online decoder https://www.aggsoft.com/ais-decoder.htm

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