[Snboard976]

I have a small black box with no identification that is connected to my radio and something else (I haven't traced the wires yet.) The boat has a Garmin 3210 chart plotter with no obvious connection to the box. It also has a Radar and Autopilot. The only obvious connection is the power for the VHF. Do you know what the black box is?

 

[sailingdog]

It looks as if it has a DB-9 serial port on it... Does it have any markings? Could it be an NMEA 0183 interface for a laptop setup at the nav console??

 

[Snboard976]

Could be, I have no clue and there are no markings. I think you are probably right and it is designed to hook a laptop into.

 

[PalmettoSailor]

That's a DSC VHF radio. Where does it get its postition data? SD Could be right and the box is a homemade interface to provide power and receive NEMA 183 for the DSC radio from laptop with a USB GPS.