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Compass Mod Values

Discussion in 'Phantom 2 Vision Discussion' started by jimre, Jan 26, 2014.

  1. jimre

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    My P2V had been flying great, but lately it's started to drift more then it used to. No longer feels rock-solid like it used to. Instead of hovering steady, it drifts in a 6-10 foot circle. Flying straight it now tends to go left. From everything I've read, this sounds like a compass calibration issue.

    So I've done several careful compass calibrations, away from buildings & concrete, no phone in my pocket, etc. Tried rotating both clockwise & counter-clockwise. Nothing made any difference. (Note - aircraft is configured for NAZA-M mode, all current updates applied to aircraft, controller, and camera).

    Hooked it up to the Phantom Assistant and looked at the Calibration values under Tools. It says the Compass Mod value should be between 750-2250. Mine says 342.9. This sounds low, right?

    However, I read in another forum that the Assistant program may have a formatting problem with this screen - not enough room to display 4 digits plus decimal. Is this true? Any way to tell for sure whether my Compass Mod value is actually 342.9 or 1342.9? It sure *looks* like there's insufficient room for 4 digits in this field.
     
  2. jimre

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    After more testing, I found out my Compass Mod value is just fine. It really was 1342.9 - not 342.9. The problem was my system text size setting in Windows - it was set to 150% in order to make text more readable on a very high-res laptop screen (2560 x 1440). Setting the text back to 100% made the Phantom Assistant text boxes display the entire number, without cutting anything off. Seems the Assistant software has some text-size scaling issues.

    Makes sense, because I've never actually gotten a compass-calibration error with LEDS or anything else. Still need to do more tests to see if I can figure out why it's started drifting more than it used to...
     
  3. Pull_Up

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    Have you tired a Basic and/or Advanced IMU calibration, too? (Ignore the temperature warning dialogue for the latter, known bug, just click through until the calibration takes).
     
  4. jimre

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    I've done a basic IMU calibration, but haven't tried Advanced yet. Probably next on my list of things to test, thx.