FA-50 + IF-NMEA2K2

[Jacob_DK]

I have an old FA-50 which I need to connect to my Raymarine backbone and display the data on an Axiom 9 RV. I have unsuccessfully used an Actisense NGW-1 to convert the NMEA0183 data to NMEA2000 (two units as I had the first replaced) but the Actisense devices were defective (input data had an amplitude of approximately 10 Vpp and output 3 Vpp). Do anyone have an idea as to what could cause the drop in amplitude if it is not the Actisense device ?

So, I am considering buying an IF-NMEA2K2 instead. As I read the manual, I should cut the PPL wire to set the data speed correctly.

But will it work ? Before I invest in yet another converter, I would like to make sure it will work.

BR,
Jacob

 

[Johnny Electron]

Without a magic wand to know if the system has a power grounding issue or just a bad or wrong converter, it is hard to say if buying a different converter would work. When using Actisense, it is normally the NGW-1-ISO-AIS unit used to convert AIS, not their normal converter. Have you spoke to Actisense support to see what they said?

 

[Jacob_DK]

Originally I bought a NGW-1-ISO but had the data speed increased to 38400 as required for AIS. So it is set to the correctly for AIS.

I have measured the input and output signals as shown in the attached photos. I guess the input amplitude (10 Vpp) is fine for a 12V system but the output of 3Vpp is not enough for the 12V system to detect the output signal.

So I am pretty sure that the converter is defective. However, the local sales office will not replace it as they believe the error is in my system. I have measured the 12V supply and it looks fine and stable (no ripple or spikes).

That's why I am considering the Furuno IF-NMEA2K2. Not too good experiences with the NGW-1 and th IF-NMEA2K2 is the same brand as my AIS and it seems easy to convert to running an AIS.

 

[Johnny Electron]

RS422 NMEA 0182 will be a 5 volt differential signal with one side going positive while the other goes negative, providing a total of 10v difference between the positive and negative when the signal is output. RS232 on the other hand will have only the positive line go positive and the negative is at signal ground. It is important that both devices are bonded to the same ground level. You might want to check with Raymarine to ensure that it accepts AIS in certified NMEA 2000 as they have in the past done some proprietary things like "Seatalk" and other special communications that require that you use their devices.

 

[Jacob_DK]

The image with a signal amplitude of 10V is the output from the FA-50 into the Actisense. That seems ok to me ?!

It is the output of the Actisense I am concerned about. An amplitude of 3V does not seem ok to me.

I will just ask Raymarine support thanks for your input once again.