Fast heading output from Raymarine EV1

[Douwe Fokkema]

Earlier I had a Raymarine 150/400 autopilot. This autopilot had a NMEA183 fast heading output. This provided heading information at a rate of 10* per second. This was connected to my chart plotter (PC with OpenCPN) and this stabilized the radar overlay and ARPA targets on the radar image. Radar is a Lowrance 4G.
After all Raymarine displays were stolen I upgraded to an Evolution autopilot with EV1 heading sensor. This autopilot is excellent, good and stable course keeping. I connected the Seatalkng (NMEA2000) to the radar interface for the heading. Raymarine states that the EV1 provides fast heading info over the Seatalkng. But the radar stabilization is poor. I checked with an Actisense how fast the heading is refreshed on the NMEA2000, this is once in every 1 to 4 seconds. Not good enough as "fast heading output".
I asked Raymarine support (NL) about the update frequency of the heading from the EV1, they say it is fast enough for their radar but refuse to communicate any further. I have no access to the Raymarine USA forum. Could any one ask there about the heading update frequency of the EV1? Any one having similar experiences with the EV1?

[Douwe Fokkema]

Just received additional information from Raymarine support (they do communicate!). For the heading they use the regular PGN 127250 and they confirm that the update rate is 10* per second.
I will further verify this.

[rgleason]

Douwe, This is not good news. I was thinking I would update my 23 year old Autohelm ST4000 Wheelpilot and fluxgate (nmea0183) with an Evo1 Wheelpilot and the new heading sensor. Our current B&G 4g radar overlay is slow when turning, but works, sort of. I hope this gets resolved. Don't know how many x's I can rebuild the autopilot control.

[Douwe Fokkema]

Hi Rick,

It seems to me that the fast heading output from the EV-1 really is there, but I haven't seen it yet. Reason to believe it is there is both the confirmation of Raymarine (prev. post) and Actisense that is adapting their NGW-1 for it, see https://actisense.desk.com/customer/...on-to-nmea1-83.
But I still have problems getting the fast heading reliably in the radar. I made some special logging for it in the pi, the heading is getting there with short interruptions and not faster than once a second. I found a bad RTNG 5 way connector, bad this is not all of the problem. I am waiting for some other components now and will test further next week.

Douwe

[Douwe Fokkema]

I did some further analysis on of the NMEA2000 network using Actisense NGT-1 and the Actisense NMEA reader software. My initial conclusions are:
- The Raymarine EV-1 does transmit a fast heading message PGN 127250 every 0.1 second
- This is the only source of the PGN 127250 on the network (according to NGT-1), so there should not be a "multiple source" issue
- The Simrad RI10 only accepts this message now and then, with 1 - 4 seconds interval. Useless as fast heading
- However the Simrad HDS7 shows under networks/source selection 2 sources of heading from the same device (E70096 == EV-1) where the first one is shown as "invalid" and the second one does not function

Attached a picture of the HDS7 screen.
On the screen the device E70096 with device id 0740277 is selected. Simrad considers this source invalid. But this is the device that Actisense NGT-1 shows. Selecting the other device with id 1160678 does not help, it gives no heading and the NGT-1 does not see this device.

My preliminary conclusion is that Simrad does not want to accept a heading from Raymarine.
Is there anybody that can give a hint on how to make this work?

[rgleason]

Very interesting. Is there any way to check the formats of nmea2k? It is seen as invalid. Maybe there is a shorter path for connections, because perhaps there is a time delay that is checked or maybe a connection that is bad?
Its all new to me, so I am not much help. Sorry. Great sleuthing. Thanks

[seandepagnier]

why don't you get an mpu9255 for $4?

It can easily output 10hz inertial data. In fact it can do 100hz. It's supported by openplotter.

I average the 100hz output to 10hz to reduce noise, and this drives my autopilot.

[Douwe Fokkema]

Originally Posted by boat_alexandra

why don't you get an mpu9255 for $4?

It can easily output 10hz inertial data. In fact it can do 100hz. It's supported by openplotter.

I average the 100hz output to 10hz to reduce noise, and this drives my autopilot.

Yes, I looked at that. But it requires some additional packaging and interfacing. But the main reason I don't use it is that I do not want two different sources of heading in my system, they will always be different.

So now I made a little interface program that reads the PGN 127250 from the EV1 on the NMEA2000 network through an Actisense NGT-1 and outputs a HDM NMEA183 message on another port. Works fine. That is actually what an Actisense NGW-1 should do, but doesn't.

[Douwe Fokkema]

The new firmware for the Actisense NGW-1 (still beta version?) does handle the fastheading output (PGN 127250) from the Raymarine EV-1 at 10 Hz. This requires that the NGW-1 is configured for that with the new Actisense configuration program ("Toolkit"). I have tested this setup and am getting a nice 10 Hz heading in as HDM sequence from the NGW-1. Finally!