Wrong Way Corrigan

[kas919]

I rarely get out of site of land, but I am noticing that my Garmin MFD and my Ritchie Compass are not reading the same heading. I would say it may be off as much as +/- 20 deg. I was thinking the other day that I should probably figure out who to believe. Of course we all assume that GPS is never wrong right? Should I have the compass professionally calibrated? Any thoughts or wisdom would be greatly appreciated. Thanks

 

[JJF]

Depending on the model of your compass, there could be adjustment screws on it.

 

[kas919]

Depending on the model of your compass, there could be adjustment screws on it.

 

[JJF]

Compensator Module (SR-CM2) - Ritchie Navigation

SR-CM2 Easily installed (see instructions) Provides up to 15 degrees of compensation Exclusive 5 Year Ritchie Warranty Made specifically for the: SS-PR2 (standard) and SR-2 (optional) Approx. Shipping Weight: .5 lb. Warning: This product may contain Cables, Printed Circuit Boards, Brass...

www.ritchienavigation.com

 

[JJF]

There appear to be three sub-models of the SR-2. Each has its own manual.

Venture
SR-2	SH-0221, BK-0023, BK-0042
SS-PR2	SH-0221, BK-0029, BK-0042

 

[DennisG01]

First check to see if you have your Garmin set to read "magnetic" as opposed to "true north".

Second... do you have any speakers/etc (sources of magnetic disturbance) close to the compass?

With the boat in your slip, does turning the wheel affect the compass? Does using/turning on any nearby electronics affect the compass?

The, yes, follow the compensation procedure (plenty of info out there about this). Look for two brass (usually brass) screws on the back side. This is a normal thing to be done based on where someone boats.