Follow up to creating Seatalk Network

Jan 22, 2008
Catalina 380 16 Rochester NY
This is a follow up to answers I have received from a previous posst, follow ups from Raymarine and more researching and downloading of manuals, pictures, Youtube videos and more!

I have purchased Axiom 9 (E70366) and upgraded to i60 Wind Package (E70061 & E22078)

The Axiom did not come with sonar and I must use an external sonar module. (I have been told that the CP200 – E70366 is compatible with the Axiom 9 – E70366)

Boat currently has legacy Autohelm ST50 Depth and Speed control heads with transducers (Z091 & Z092)

Boat currently has SPX-10 Autopilot (E12198) with Fluxgate Compass (M81190) and Autohelm Rudder Sensor (similar to current Raymarine model). SPX-10 is connected to P70 AP Control Head (E22166)

I have enclosed diagram that I have updated after input from everyone.

Can I do the following:

Connect the legacy TXD’s for depth and speed AND new i60 Wind TXD from the iTC-5 (E70010) to the CP200 Sonar Module (E70266) and then connect them to Seatalkng 5 way (A06064)
Replace legacy transducers with new DST800 (A22154)

Is the DST800 compatible with the CP200?
If so, can I connect it to the iTC-5? And then to the CP200?

Can I connect the ST50 control heads through the D244 junction box to the Seatalk to Seatalkng Converter (E22158)
By doing so, will they receive the correct information from either the legacy TXD’s that are run through the iTC-5 and/or the CP200?

Will this information still also go to the Axiom 9?

The SPX-10 accepts the Autohelm Rudder Sensor and the Fluxgate Compass DIRECTLY into the CPU
It also provides for the option to be powered but I will set it up so that it does not power the Seatalk Network.
The Seatalk Network will be powered by the Axiom 9 cable that connects to the Seatalk Network

The SPX-10 is then connected to the Seatalkng 5 Way?

The wrench now is that the Axiom 9 I have doesn't allow for sonar without the external sonar module.

Is my diagram accurate?

Thanks for any help.



May 2, 2014
Hunter 30 St.Petersburg, Fl
I can't answer all your questions, I can just tell you I have an Axiom 7. ST60 speed and depth, which is connected to the st/stng adapter, and it does not send depth and speed to the axiom. Not sure those instruments put any info out onto the network? Sorry, that's all I have.
Oct 22, 2014
CAL 35 Cruiser moored EVERETT WA
At first glance I note that you are powering the backbone at one end (the Axiom) and you need to consider the power balance on the back bone. A carful read of the instructions will say to provide power in the middle of the backbone so that it is balanced. Each of the attaching displays has a value. The power needs to be distributed evenly.

I thought the iTC-5 also required a power connection. I know I have one and it runs the transducer that feeds depth info to the backbone.

Maybe one of the Seatalk wizards like @LeslieTroyer can add more detail.
May 20, 2016
Catalina 36 MK1 94 Everett, WA
I believe John is correct. The power cable for the Axiom just powers the axiom, not the buss. In order to be compliant with N2K it would need jumpers or some other way to NOT power the buss (line the EVO2 autopilot) Get a red/black cable and power up the buss.

also put black plugs into the open white plugs on the STng 5way and ITC5
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Jan 22, 2008
Catalina 380 16 Rochester NY
Ok, I think I can add the power supply anywhere.
I know the SPX10 allows for it to be powered but to not send power to the back bone. That's why I thought I'd keep that as a stand alone...

Everything I've read and received so far says that the Axiom will only receive data from the ST legacy transducers if it's through the iTC-5. It may not be accurate or have to be calibrated but it will receive the info.

That's why I upgraded to the i60 Wind package, so that the data is correct once it goes to the Axiom and SPX-10.

My other question is whether the external sonar module (I have the SP200) will accept data from the legacy transducers and transmit it correctly to the Axiom 9 either directly or through the iTC-5.

I have these same questions out to Raymarine, but their turn around on answering questions is about 5 days (usually the response is barely understandable in english...unfortunately) and their 800 hotline takes hours to get through to....

Thanks so far!!!
Sep 20, 2006
Hunter 33 Georgian Bay, Ontario, Canada
I can't answer all your questions, I can just tell you I have an Axiom 7. ST60 speed and depth, which is connected to the st/stng adapter, and it does not send depth and speed to the axiom. Not sure those instruments put any info out onto the network? Sorry, that's all I have.
I have the exact same set up and can get speed, depth, wind on the Axiom 7.
Oct 22, 2014
CAL 35 Cruiser moored EVERETT WA
It is said "we do not know what we don't know."

To help with the confusion Raymarine proprietary structuring of their system and connections lead us to misunderstand what seems normal/natural to do.

Here is a link that might help with the deciphering. Networking | Raymarine
There is a manual I found online titled "SeatalkNG" which provided clarity when I was trying to figure this stuff out.

"the Axiom will only receive data from the ST legacy transducers"
I do not read that in the manual. The Axiom (depending on which of the units you are considering), has a port for legacy transducer units.

Note that your sonar is more than the transducer on/in the hull of your boat. It includes the power system to send the signal down to the bottom and an interpretation computer module to decipher the signal and decide on how far away the bottom is from the transmitter. The iTC-5 provides the function and then puts it on the SeatalkNG backbone as a nmea2000 readable data stream. I am using this function from my iTC-5 unit to speak to my wifi gateway so that I can get the depth data on a wifi connected iPad.

You will need to locate your power to the backbone (SeatalkNG system) somewhere in the middle of the backbone. You cannot put it on one end then hope that all of the spurs are evenly getting the power form the system that they need to run.

Good Luck.
Jan 22, 2008
Catalina 380 16 Rochester NY
Hi John

It's also said 'that the sum total of what I know that others don't know would stun a team of oxen in their tracks'!!!!
Sadly, in my case it's the sum total of what I DO NOT KNOW!!!!

But, this has been very helpful.
I can easily put the power source in the middle and it may have been more of a matter of convenience as I was making the schematic....something I can fix.

I have seen those links, downloaded them and researched them, I just want to be sure I have all the right parts and tools.
The picture of the Axiom you have is very close to mine. Unfortunately, my model E70366 does not have a transducer/sonar female plug. It is a blank cap because this model didn't come with an internal graphic cpu for depth or 'fish finding'. The E70366 needs an external sonar module or something along that line for depth.

I have access to the CP200 external sonar module, but the only transducer that works with it is the CPT200 transducer, which is a stern mounted version. That won't work....

So here are the 2 responses from Raymarine. They were VERY fast this time and their response came the same day. I must have hit them at a bad time before!

First response to my question (which was similar to my first post)

Good Morning
You can connect the old transducers to the ITC5. But the calibration will have to be done by Axiom and not by the displays.
The CP200 must connect it to the AXIOM via Raynet cable and use its dedicated transducer (CPT200 - A80281)
The DST800 is not compatible with the CP200
It can use the D244 and all data will be present on the Axiom and the ST50
Compass and rudder must be connected directly to the SPX. The power supply can be turned off on the seatalk line
The attached diagram is correct.
The CP200 module can only be connected via Raynet network and must only use its dedicated transducer (CPT-200)

Best regards

Alessandro Lazzarini

I then followed up with:
First THANK YOU for the fast turn around on the answer.
So I leave out the CP200 all together, the legacy ST50 transducers can connect via the iTC-5 and will then talk to the Axiom 9 and ST50 control heads.

If I wanted to upgrade to the the DST800 transducer in the future, what external sonar module would I need to communicate with the Axiom 9?
Thanks again

And their final response was:

The DST800 connects directly to the StNg line or at ITC5 ( depend to the model )
You don't need a module, you will see the data on the Axiom.
This transducer, however, gives the depth data alone (it does not have a fishfinder type graphic display)

Alessandro Lazzarini

So the DST800 is out...for now.
It appears I can use my old depth and speed transducers and lose out on temp and any type of pictorial rendition of the seabed

And...aside from making sure the power setup is right, all else should work.

I will know in about 4 weeks!

Please, let me know if I've missed something. I wanted to include Raymarine's responses for folks like me that might search in the future.



Oct 22, 2014
CAL 35 Cruiser moored EVERETT WA
I now better understand which Axiom you have and you are correct about the lack of internal sonar systems.

As Raymarine indicated, you can use the old transducer (likely a 200kHz - shallow depth or a 50kHz - deep depth), with the iTC-5 unit. That is what I did. Works great. My old transducer can recognize up to about 275ft. Then it returns - - - - . I figure with my boat anything beyond 5 ft is golden. The iTC-5 puts the depth message into the SeatalkNG (NMEA2000 - N2K) backbone for any N2K reading MFD to display.

That is why you can do away with the CP200.

This link my share additional insight into SONAR functions....

Ward H

Nov 7, 2011
Catalina 30 Mk II Barnegat, NJ
Looks like you are closing in on your system. Here are a few of suggestions.
1. Replace the i60 with i70S and buy the wind transducer seperate. The i70S will give you calibration function of the wind and legacy depth and speed transducers. i70S has multiple screens (10 I believe) you can scroll thru, including one that mimics the screen of the i60. Pricing will be close.
2. Connect your STng power supply to the ITC spur connection. Run one backbone from the iTC5 up your pedestal and put the 5 way connector in the instrument pod. Your Axiom, P70 and i70S will connect to the 5 way. Run your other backbone from the iTC5 to your SeaTalk connector. That puts the power supply just about in the middle of your system.
3. I believe you were hoping to use the ST50s as displays below decks. Without reviewing the previous thread I believe they are not listed as supported but someone posted they will work with the ST to STng convertor. Give it a try and if they don't work budget in a i70S for below. A cheaper route might be to install a Yacht Devices WiFi Gateway and use an old iPad or other tablet to as a display in the cabin.
4. If you really want water temp, replace your old speed transducer with E26031 ST800/P120 Speed Temp transducer. It can be found for under $60. Easy replacement but you will have to install the new thru hull tube that comes with it. I remember it has fitting the same hole.

Note - There is a package offered that contains the i70S, iTC5, Wind Transducer and DST800 Speed/Depth/Temp. The only thing I don't like with the DST800 is that many pull the Speed Transducer between sails to keep the paddle wheel clean from growth. With it out you can't check the depth.
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May 2, 2014
Hunter 30 St.Petersburg, Fl
Yes I do see the converter, but no depth or speed? There is power to it as well.
Jun 3, 2004
Catalina 34MKII 1717 Merritt Island, FL
I am having the same issue. Raymarine told me to get a replacement converter. I will be receiving it today. Please let me know if you have solved the issue...gary