Contemplating upgrading the electronics in my KK39 for coastal cruising and in the near future going to the Bahamas. Below is a list of the current electronics, any recommendations to upgrade or add at this time would be appreciated?
Garmin GPSMap XSM chartplotter (2018)
Garmin Fish-finder 240Blue depth-sounder
Simrad AP28 autopilot
Standard Horizon VHF (2)
Matrix GX 2150 AIS
Flybridge
Chartplotter:Lowrance (portable)
Standard Horizon VHF (1)
For capability, I would recommend adding an AIS transceiver (transmit and receive) and RADAR, as well as autopilot control from the flybridge.
Lots of ways to get there…it may make sense to add a Garmin MFD to the flybridge, then add a Garmin RADAR that will display at both MFDs. Essentially most AIS transceivers will network in with the MFDs. Finally, another autopilot control is easy to add.
Your current stuff sounds OK.
The Garmin XSM could be current, one, or two generations old... I think. Ours is a 7612xsm possibly installed circa 2015. Since then, Garmin has replaced that series with an 86..xsm, and then I think a 12..xsm or 16..xsm or something like that.
We can still get Garmin chart updates, so I guess that'd be true on the newer ones, too. The newer models may also offer an advantage (?) of using some newer Navionics charts since Garmin acquired them. (Ours won't.) Garmin charges for annual chart updates though -- unlike Furuno for annual NOAA chart updates.
I'd tend to agree with Irene, though. Add radar and add AIS. Work out how to display radar at both helms -- which suggests another Garmin MFD.
I'd also add AP control on the flybridge.
And I'd add another depth sounder, partly for redundancy, partly to see a different opinion about current depths. 50/200 Hz and 235 Hz sound sounders seem to co-exist easily enough.
There's a thing about charts. I've read a) Navionics charts for the Bahamas aren't great, and b) Explorer charts for the Bahamas are the bee's knees. Garmin won't do Explorer charts, as far as I know. I think Explorer charts are included in some C-Map packages. That could influence your choice of second MFD, although I think radar at both stations is maybe more important... especially because you could probably solve the Explorer charts with a separate tablet solution... which would also add another layer of redundancy anyway.
-Chris