Full Version: GPS & Compass
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I have the Moitessier HAT. I had an issue with no GPS data that has been resolved by removing my SSD. This, in my opinion, is a step backwards. Secondly, the compass in the HAT is unreliable. It rotates around wildly due to the RF interference in my project.

The compass I. Opencpn gets its data from the Hat's compass, OT from the GPS heading, doesn't it? 

Due to this, I'd like to move my GPS (or GPS antenna) and compass outside of my project and I don't really know where to start.  I tried a cheap $10 Amazon GPS antenna attached to the HAT and it had poorer performance than the antenna from the HAT.

So, any guidance will be greatly appreciated.
The compass in the Moitessier HAT, as any compass, needs to be calibrated or you will get wrong data. You should be able to calibrate even when it is placed close to metallic objects but if you put the HAT close to speakers or any big magnetic interference you will not be able to calibrate any compass.

We recommend this active antenna to be connected to the Moitessier HAT, it works like a charm: for cases when the built-in antenna is not enough. but most cases do not need an external antenna.

"The compass I. Opencpn gets its data from the Hat's compass, OT from the GPS heading, doesn't it? "

Sorry I do not understand this question, could you be more specific?
Can you point me to directions of how to calibrate the compass? The only button that I can get to do anything in the pypilot calibration is the one to set the boat to level.

I switch to the other tabs, accelerometer, compass, etc and none of the other buttons seem to do anything. When I rotate my project, you can see the yellow dots appear I. The blue globe as it spins.
Turns out I was calibrating the accelerometer and compass correctly.  Same as I used to do in my drone building days. 

I must have had a bad external GPS antenna because the GPS never connected to a satellite when using it.

I went back to Amazon and bought a Garmin marine GPS antenna and am really happy with the performance.  Even inside my house, the OP GPS will lock onto 12 satellites within seconds, then bounces around between 8-12.  Outside is even even better.  I was a little worried that this antenna would be compatible, but turns out it is. 

[Image: OP-GPS-View.jpg]

[Image: Garmin-GPS-Antenna.jpg]

[Image: Amazon-Garmin.png]