Originally Posted by louiseevans
We have a Comar AIS multi receiver/splitter unit; They recommend wiring it up to the VHF radio, but we're going to use it in conjunction with the chart plotter (Raymarine C Series), not the computer and not necessarily have the VHF on. Does the antennae need a power source from the VHF to make it work? Or can we wire the AIS directly to the chart plotter, use its power rather than the VHF as a power source?
2) Is there a dedicated Raymarine jack plug and lead that i have to use, can't find one in Budget Marine catalogue? (Curacao)
It depends on the antennas design. Some antennas are just an antenna with a coax that leads directly to the GPS
unit for satellite
signal processing. Other GPS
antennas process the satellite
signals at the antenna and output a NMEA
sentence which can be sent to whichever device will accept a NMEA
sentence. The latter type of antenna needs to be powered by 12 volts DC. The former is unpowered.
Your VHF radio does not require an AIS or NMEA connection to function as two-way radio. It does require a NMEA position sentence for the DSC
function to work. If it is also an AIS type of VHF radio that displays basic AIS information, then obviously it needs an AIS signal for that function to work...unless it has its own built in AIS signal processing, which it probably does. You can always have your VHF on with the sound down so you do not have to hear the noise
, then you can still use the AIS out of the VHF.
You can split an AIS or NMEA signal between two or more receiving devices since the signal travels only one way.
Use the boats 12 VDC as the power source for your AIS receiver so you are not reliant on the VHF being turned on in order for your AIS receiver to function. You want to avoid daisy chaining power sources in case one fails it does not cause another to not function. I run some of my nav equipment
to a common bus bar, which is fused. Each nav instrument still has its own inline fuse.