High hdop and compass offsets

On my Pixhawk, I’ve got a dhop ranging from 2.1 to 3.4 and a z compass offset of 220. Is that way out of range? Doesn’t matter how many time I calibrate the compass I still get 220. Any thoughts?

What is your hardware configuration?

I would recommend you to try outdoors to avoid any interference, and to try the calibration dance:
youtube.com/watch?v=-_mjfPlHL9o

I tried the original and the dance lol. Both gave me the same results.

[quote=“RogelioN”]I would recommend you to try outdoors to avoid any interference, and to try the calibration dance:
youtube.com/watch?v=-_mjfPlHL9o[/quote]

Right now I’ve got a Pixhawk on a Tarot 650 quad just for testing. Trying to work out any bugs before it goes on a large mapping hex. Hardware is as follows:
Tarot 650 frame
Afro 30esc’s
1355 Tarot props
4s 5000mah batt
Pixhawk
3DR compass/mag 15cm above the frame
3DR power module
3DR radio

Have you done a compassmot? Might help your compass offsets, though I doubt it will help the hdop. I tend to get hdop values higher than 2 when indoors, and they’ll drop to around 1 once I walk outside.

Compassmot doesn’t do anything about the offsets! It only corrects for EMI through the drivetrain.
If you have bad offsets, you probably have something ferrometallic too close to the compass, e.g. screws or something like that. You should try relocating the compass on the frame.
HDOP is usually bad indoors. Additionally, we currently have a sun activity high, so at times, the GPS system can go a bit haywire. Check space weather and expected GPS precision for your location from the web.
Also, some electronics, such as the Hobby King Wing Camera 720p are jamming GPS with up to 15cm range.

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Well, I’m at a loss. Even though it’s not an issue the mot is 0%. And as you can see from the image, it’s nowhere near anything ferric.

Did you do the compass dance outside? Maybe try changing the place. In the docs is a list of minimum distances from all kinds of stuff for calibration.
I live in a typical Finnish wooden house and my first attempts on calibration 2 years ago failed miserably - in the garden. It took me hours to figure out the reason…:
Then, I had an old CRT TV in the living room, which was 3m and 2 wood layers plus a bit of rock wool away from my copter, and my then-girl-friend was watching TV. Those old CRT TVs have basically powerful electric magnets in them.
After pulling the power from the TV, calibration worked just fine.
Some LiPo warners have pretty strong magnets in the beepers/speakers. Those can also mess with the compass.