ST50+ might not be working

Jan 22, 2008
Catalina 380 16 Rochester NY
As I reported, I believe I have successfully installed RM network that allows communication between:
Axiom 9 MFD
i60 Wind transducer and Control Head
SPX-10 Autopilot
P70 Autopilot control head
GX2000 VHF radio with Camino 108s that provides AIS to radio and Axiom 9
Old Autohelm ST50+ Depth and Speed control heads with their original transducers.
The speed, depth and wind transducers are connected to an ITC 5
The ST50+'s are connected to a D244 junction block and then that is connected to Seatalk to SeatalkNG converter block

Everything has been connected and installed.

The Camino sends out my AIS data (people have seen my boat on their AIS receivers)
The GX200 and the Axiom 9 receive the AIS data and the Axiom 9 shows other AIS boats in my area.

The i60 control head shows wind and direction. It isn't right, but I have not calibrated the instrument or moved the boat at all.
It was put in the water this week and all I did was motor over to my slip.

The wind speed and direction show up on the Axiom 9

I am not sure about the SPX-10 autopilot. The P70 control head shows rudder sensor data, correct heading (well at least it is showing that my boat is pointed 300 degrees north at the moment)
I will mess around with all that when I get on to open water.

My question is about the ST50+ Depth and Speed.
On the ITC-5, the lights are blinking for the Depth and Speed, the light is steady for the WInd.
On the ST50+ gauges, the Speed is showing 0.0, the Depth is blinking 0.0

When I go into the Axiom 9 Network Settings, it will allow me to 'calibrate' the speed by setting ST50+ indicated speed to whatever the GPS on the Axiom 9 shows (I think)
However, the depth option is grayed out and I cannot hit it.

I just don't think the transducers are not working.

Am I missing something? Or is there something I should be looking for?


Toole'n Around
Catalina 380 #16
Rochester, NY


Oct 22, 2014
CAL 35 Cruiser moored EVERETT WA
Perhaps it is communication issue.
The ITC-5 outputs NMEA2000 data streams (Raymarine calls it SEATALKng) from NMEA0183 transducers. Your ST50Plus uses NMEA0183 data from the transducer and can not understand SEATALKng, just like I cannot understand Greek even if I am being yelled at.

Raymarine iTC-5 Instrument Transducer Converter
Transducer signals are easily converted to SeaTalkng
The link provides connection data. Raymarine iTC-5 Instrument Transducer Converter
Note the way the ITC-5 is attached to the "I50" displays. They understand SEATALKng. Note the termination plug for the ITC-5.
  • Helpful
Likes: JamesG161
Jan 22, 2008
Catalina 380 16 Rochester NY
I noticed the termination plug in the one diagram, yet in the other that uses two ITC-5's the terminal plugs are elsewhere.
I was told that the ITC would allow the old Autohelm control heads to act like 'repeaters'

I'm going to take the boat out tomorrow for first time and see if actually getting the speed wheel to turn will activate the speed transducer and also swing the boat to calibrate the compass for the wind instruments.

I will report back my findings.

  • Like
Likes: jssailem
May 20, 2016
Catalina 36 MK1 94 Everett, WA
If you use the ITC5 to process wind, depth,& Speed your old display heads are not going to work at all. The ITC5 is not a repeater. It can be part of a backbone using the two blue connections - or a standard device using the white connector - not both

If you connect the old heads to the appropriate heads, and use a ST-STng converter youll

Ward H

Nov 7, 2011
Catalina 30 Mk II Barnegat, NJ
Transducers do not use either NMEA network. (unless you buy the new Smart transducers which plug into the network as a device).
Either a display head or the iTC5 are needed to "drive" the transducers and interpret the signals returned.
The iTC5 needs a STng display head or i70 multi screen display head to calibrate the depth and speed transducers. The Axiom will not do the calibration.
Then what @LeslieTroyer said.
Jan 22, 2008
Catalina 380 16 Rochester NY
Thank you.
I was told by Raymarine that using a D244 to connect the 2 ST50+ control heads together and then running a Seatalk spur from the D244 to the Seatalk to SeatalkNG connector AND also running a spur from the ITC-5 which is connected to my wind, speed and depth transducers would allow the 2 old Autohelm ST50+ to act like repeaters.

I will say that I am getting depth and speed on the Axiom 9 and the Axiom 9 and my P70 Autopilot control head are receiving wind information from the new i60

Is it possible that I have mixed the wiring up on the ST50's? I had to splice those to connect them together to the D244 and there wasn't a good diagram for wiring, although I thought I had done them correctly.