Simrad/Navico MARPA problem

[tanglewood]

In another thread I promised to provide details on the Simrad/Navico problem with its radar MARPA function. Here is a posting with all the details, including a couple of easy test to see if your radar has the same problem. This was readily reproducable on my boat with both a 4G radar and a 10kw open array. Both were controlled by a Simrad NSO EVOII, and used an HS70 sat compass for position and heading. What you see is very broken.

[tanglewood]

By the way, I'd be very interested to hear if others can reproduce these results. I've spoken with 3 other Simrad owners who I know, and two others who I don't know personally, and they all have the same problem. Most of them though it was normal until they realized how it should work.

[Dockhead]

I had a very frustrating problem with radar heading, but I don't think it was the same one.

Once I had two heading sources on the network, the radar would stubbornly grab the wrong one, no matter how I set up sources in the network controls. Which would of course ruin MARPA, overlay, and radar bearings. I had a devil of a time figuring out what was going on in the first place. When I figured it out, there was no cure. So I had to take the device off line (a Simrad GNSS receiver with built in compass). This was all happening over the course of a 3000 mile cruise -- PITA.

I finally got qualified tech support from Navico who frankly admitted that it was a bug. It was cured with a software update for the radar control.

We'll see if there some other bug which is degrading the MARPA performance. Could be that this was cured by the same software update. I'll see as soon as I can get the vessel to sea.

[44'cruisingcat]

Simrad does seem to release some buggy software.

[tanglewood]

Originally Posted by Dockhead

I had a very frustrating problem with radar heading, but I don't think it was the same one.

Once I had two heading sources on the network, the radar would stubbornly grab the wrong one, no matter how I set up sources in the network controls. Which would of course ruin MARPA, overlay, and radar bearings. I had a devil of a time figuring out what was going on in the first place. When I figured it out, there was no cure. So I had to take the device off line (a Simrad GNSS receiver with built in compass). This was all happening over the course of a 3000 mile cruise -- PITA.

I finally got qualified tech support from Navico who frankly admitted that it was a bug. It was cured with a software update for the radar control.

We'll see if there some other bug which is degrading the MARPA performance. Could be that this was cured by the same software update. I'll see as soon as I can get the vessel to sea.

FWIW - stripping my network to the bare minimum, including a single heading source, was one of the experiments that Navico engineering asked me to do. They originally exected this to be a source selection problem. The issue reproduced with nothing but the NSO, 10KW radar, OP40 control panel, and HS70 on the network. So not a source selection problem.

Also, all sw revs were reviewed by Navico and confirmed to be the latest and greatest of everything.

The N2K bus was also gone over with a fine tooth comb and passed inspection with flying colors.

They ultimately agreed there was a problem that they needed to fix, and that it wasn't a simple source selection issue as they had originally hoped.

[Dockhead]

Here's one problem I know the answer to:

"Problem # 6:

This is another ARPA problem. If you lock onto a target, then shut off the autopilot, the ARPA vector swerves off about 90 deg from the actual course of the target. These two systems should have nothing to do with each other. Why turning off the AP impacts ARPA is beyond me, but it does. A friend tried the same experiment on his Simrad equipped boat and got the same results."

The pilot is capable of making all kinds of navigational calculations including TWA, TWS, COG, SOG, and many others. This is a relic from the days when the pilot was the only smart device on board, and probably continues so that it is possible to run a network without a plotter on it.

I also had different problems from the pilot making these calculations differently from the MFD, including a persistent and annoying "wind shift" alarm when using the pilot in wind mode.

The cure is to shut down those functions in the pilot setup menu. I'm sure that's what this problem was, although I guess it doesn't matter to you anymore since you've gotten rid of that equipment. Maybe useful for someone else.

[tanglewood]

Originally Posted by Dockhead

The cure is to shut down those functions in the pilot setup menu. I'm sure that's what this problem was, although I guess it doesn't matter to you anymore since you've gotten rid of that equipment. Maybe useful for someone else.

Very interesting. How do you turn those things off? I'm not remembering how to do that.