Ok, thanks.. I think they both have NMEA2000 so maybe the GPS could share the signal off the VHF radio if needed. But, as you say, it likely isn't needed for high accuracy on the plotter in recreational use. Relative to the VHF, I may be in waters with commercial vessels from time to time so want to make sure I have AIS with good accuracy so I will go with the remote antenna on the VHF radio at least. That antenna is $90 for the Standard Horizon GX2400.
How long have you been boating?
Your way over thinking this
The government commits to broadcasting the GPS signal in space with a global average user range error (URE) of ≤7.8 m (25.6 ft.), with 95% probability.
Actual performance typically exceeds specification, but there is no guarantee of it being better. Using a remote antenna isn't going to make it any better. Save your money and put it towards a larger display on the combo unit noted below
I boat in some of the busiest shipping lanes in world. Unless running in adverse conditions, visibility of an approaching vessel is upwards of 10 to 15 miles. Certainly don't need AIS to alert you to an approaching vessel that your "watch" can see.
Besides, If you don't have a chart plotter, where are you going to display the AIS data?
To keep cost down, I suggest a Fish finder/ Chart plotter combo. I would look at the Garmin EchoMap series. Should be some decent sales as they roll out next years models over the next couple of weeks.
Buy the biggest screen size you can afford.
I would then go with a Standard Horizon GX1400G VHF to say some money. Can get the GPS signal from the combo via (hardwired) NMEA 0183.
If you want to get fancy and spend a bunch more money, you can install a NMEA 2000 backbone ($100) then go with GX1850 VHF. Feed the GPS signal to the VHF via NMEA 2000. A lot of money to spend unless your going with a full blown NMEA 2000 network system in the future.
A CB is useless on the water.
Have never used a hailing speaker in all my years on the water.
