Simrad EVO2 Radar/Chartplotter Misalignment

[Bob Bradley]

My new 45C has Simrad EVO2 electronics. I've been experiencing a significant misalignment problem between the chartplotter course and the Radar Course To Steer line. In the following pics (sorry about the quality - I was running the boat while taking them) I have set a course to a point just east of the Lords Passage buoy off Fishers Island. That shows on the chartplotter screen. On the radar screen, I am navigating directly toward the buoy - it is the blip in my heading line. The course to steer line wants me to steer well to the left of the buoy, despite the fact that the waypoint is well to the right of the buoy. I have the latest software available installed and have done a hard reset of the system. Any suggestions other than the obvious one (call Scott and buy a Furuno system)?

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[Bob Bradley]

Later at the dock, I set a course to a waypoint across the river from me, at the foot of the dock at the marina there. The radar wants me to steer well to the left of the target. By the way, the radar returns are accurate. In the pic above on the first post, I am running directly toward the buoy and it appears properly on my heading. Here's the pics from at my dock:

The crosshairs on the radar screen are approximately where the waypoint on the charplotter is.

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[Avenger]

Probably a stupid question, but could this be a true North vs. magnetic setting issue? Or, chart datum set incorrectly?

[Bob Bradley]

I doubt that its a compass (T vs M) issue, and I'm not technical enough to know much about the chart datum.

[Boatsb]

You know the answer.

Although if you call I may know what needs to be changed.

[MadHatter53]

Maybe it’s the antenna or the elect compass. Move the antenna/compass until it lines up then see how it is in real-time.

[Pascal]

It doesn’t seem to be a compass or heading issue. It looks to me like your waypoints are not where they should be on your radar screen. It s pretty clear on the second example. I don’t think it’s a datum or offset issue as if that was the case you would notice your position would be off on the plotter.

Not familiar if you put your radar cursor on the waypoint shown on the radar screen, does it show the same coordinate as the WP on the plotter?

[Captain Ralph]

Was just thinking, Radar zero degree alignment not preformed?

[Bob Bradley]

The radar seems to pick up targets accurately. In the first pics I posted, the target on my heading is displayed where it should be. Only the waypoint is located incorrectly on the radar screen. When I run in overlay mode the radar returns appear away from the corresponding chart items.

[racclarkson@gmail.com]

Then I think you need to ensure radar bearing is perfect. After that, sounds like your flux gate needs re-initializing. A COG and heading disagreement will cause the problem you’re experiencing. The COG, most likely, will be correct as it’s generated by GPS. It’s possible your compass is picking up some ferrous metal or stray current. For example, I found a 13 degree flux gate swing just by energizing my port engine ignition circuit. Moved the compass and right on track.