Radar Overlay Problem

[Dockhead]

I have a weird problem with the radar overlay on my new system (2x Zeus plotters and 4G radar). It started to occur after I updated the software on the plotters and radar.

What happens is this -- the radar displays perfectly on the radar screen. The bearing line is perfectly aligned with the bow of the boat. Radar blobs correspond exactly with AIS symbols. Only . . . the heading shown on the compass ring in the radar screen is wrong -- 18 degrees off, consistently.

On the chart screen, the radar picture is skewed by the same 18 degrees.

I tried changing the "adjust bearing alignment" in the "installation" setup menu, and I could in that way get the radar picture to line up, but then the radar screen is off.

When I open "radar status", I see that there is a line for "heading on radar", where it says "yes, mag: 345 degrees mag". This is the false heading -- the real heading, according to my heading sensor and also according to my regular steering compass, is 18 degrees different from that.

It also says "Heading on network: valid", and "error codes -- none", and "radar overlay status -- ok".

Why would the radar have its own heading, and why would it be so far off the heading on the sensor? Does the radar have its own heading sensor? I don't think so, and I can't find any place to set it up anywhere.

Anyone have any clue? Seems really weird to me.

[zboss]

Occasionally, I have an same issue but with Garmin equipment. I found that I solved it by going through the autopilot setup, which basically has you driving around in circles until all the systems can recalibrate.

[smac999]

sounds like you have a mag vs true heading issue. set everything to the same

set the radar bearing offset using the radar only. heading doesn't effect this. sounds like you had it right.

if the land aligns with the radar picture then everything is good. if it is not aligning then your heading is wrong.

if just the vaule is wrong. it's probably showing true vs mag. I dont' know what it is over there. but here it's about 19 degrees difference (different everywhere in the world)

[Dockhead]

Originally Posted by smac999

sounds like you have a mag vs true heading issue. set everything to the same

set the radar bearing offset using the radar only. heading doesn't effect this. sounds like you had it right.

if the land aligns with the radar picture then everything is good. if it is not aligning then your heading is wrong.

if just the vaule is wrong. it's probably showing true vs mag. I dont' know what it is over there. but here it's about 19 degrees difference (different everywhere in the world)

Variation is less than 2 degrees here, so that can't account for it.

Everything in my system is set to magnetic.

Anyone else have any ideas?

[ColdEH]

If it was good with the last software , maybe you could go back to it . My Simrad NSS 7 came with the latest software , I wonder if it will have the same issue when I install 3G .

Have you sent Navico the question?

Regards

[Dockhead]

Some more clues:

When the new software installed, I somehow got two radars: Broadband 4G - 2901 A and Broadband 4G - 2901 B. I can't see how to remove one of them. I can choose either one in the Installation menu, and they both work the same. (Of course there is only one physical radar).

I have tried "Reset device ID" but this does nothing; also "Reset radar to factory defaults."



Yes, I've sent this info to Navico; waiting for their response. I thought maybe someone else had run into this.

Another clue: When the radar power is off, the correct heading is shown on the (empty) radar screen. It flips over to the wrong heading when the radar starts transmitting.

[Lodesman]

Are you certain the radar antenna is aligned correctly?

[Dockhead]

Originally Posted by Lodesman

Are you certain the radar antenna is aligned correctly?

Yes.

And I use the radar screen always in "Heading Up" mode, and the heading line corresponds to what is directly in front of the boat, even though the numbers on the heading ring are wrong.

The numbers on the heading ring are right, as long as the radar is not transmitting.

[ColdEH]

So, it was all fine with the old software? If it was then it is a software issue for sure . What version did you install , I haven't been on the Simrad site in a while but I will check my version that I have installed . Did you try reloading it . Also, this wasn't a Beta version was it ?

Regards

[Dave Lochner]

Originally Posted by Dockhead

Yes.

And I use the radar screen always in "Heading Up" mode, and the heading line corresponds to what is directly in front of the boat, even though the numbers on the heading ring are wrong.

The numbers on the heading ring are right, as long as the radar is not transmitting.

It sounds like something is interfering with the fluxgate compass. Are any of the wires for the radar near the compass? Any part of the radar located near the fluxgate compass?

Is the 18 degree error consistent across all boat headings?

[ColdEH]

Dockhead , did you get her fixed up ??


Regards

[Dockhead]

Originally Posted by typhoon

Dockhead , did you get her fixed up ??


Regards

No indeed

First advice from Navico tech support was to do a master reset to both Zeuses. Other than losing all my setup and settings, this did nothing. Waiting for the next suggestions from Navico. I'll post a follow up as this thing progresses.

[tartansail]

Are you also using a Navico AP or do you use a different one with its own fluxgate compass? I still have my Raymarine AP. When I was getting the Zeus set up, the tech mentioned that some of the Zeus functions will read heading off the Ray compass. If I saw strange headings, I should look there. Unfortunately, I wasn't paying close attention since I was working on something else and the headings were aligned. However, if you've got more than one compass on the network, you might look into that possibility.

[Dockhead]

Originally Posted by tartansail

Are you also using a Navico AP or do you use a different one with its own fluxgate compass? I still have my Raymarine AP. When I was getting the Zeus set up, the tech mentioned that some of the Zeus functions will read heading off the Ray compass. If I saw strange headings, I should look there. Unfortunately, I wasn't paying close attention since I was working on something else and the headings were aligned. However, if you've got more than one compass on the network, you might look into that possibility.

That's a good idea!!! The problem started when I updated the software in the two Zeuses and the radar. However! I also installed a new Simrad GPS/heading sensor at the same time!!! The heading sensor in the Simrad GPS is not used and has not been set up, but possibly the radar is grabbing that data for some reason. Great idea!!!

What I'll do is just disconnect it and use a different source for position (built in GPS in the Zeus). I'll post the results. Ha, thanks!

[Dockhead]

Originally Posted by tartansail

Are you also using a Navico AP or do you use a different one with its own fluxgate compass? I still have my Raymarine AP. When I was getting the Zeus set up, the tech mentioned that some of the Zeus functions will read heading off the Ray compass. If I saw strange headings, I should look there. Unfortunately, I wasn't paying close attention since I was working on something else and the headings were aligned. However, if you've got more than one compass on the network, you might look into that possibility.

I owe you a beer!!!

Disconnected the GS25 and the problem disappeared! The radar was grabbing heading data from the GS25 (heading sensor is unused and therefore uncalibrated). Contrary to the network configuration.

I have written to Navico tech support to ask why.

Hope this helps someone else with a similar problem.