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Senn

macrumors member
Original poster
Jun 10, 2009
45
0
So the compass app and the compass feature in google maps does not work while Im in my car. It says there is interference and it cant calibrate. If I get out of my car it works fine.


If the metal in a car does indeed interfere with the compass..then this is completely useless. I was only happy because I thought it could tell which direction Im heading while driving..and so far that doesnt work.
 

iGary

Guest
May 26, 2004
19,580
7
Randy's House
So the compass app and the compass feature in google maps does not work while Im in my car. It says there is interference and it cant calibrate. If I get out of my car it works fine.


If the metal in a car does indeed interfere with the compass..then this is completely useless. I was only happy because I thought it could tell which direction Im heading while driving..and so far that doesnt work.

Your car is a big hunk of metal, that's what is interfering.

The compass is intended for foot use.
 

Stangs55

macrumors 6502a
Jul 3, 2007
777
46
The Lone Star State
Sorry...but just metal should not interfere.... Now maybe there are some electronics or an in-car compass that is interfering....but not the frame of the car.
 

rorschach

macrumors 68020
Jul 27, 2003
2,272
1,856
So the compass app and the compass feature in google maps does not work while Im in my car. It says there is interference and it cant calibrate. If I get out of my car it works fine.


If the metal in a car does indeed interfere with the compass..then this is completely useless. I was only happy because I thought it could tell which direction Im heading while driving..and so far that doesnt work.

From Apple:
http://support.apple.com/kb/TS2767

If you wish to mount iPhone 3G S on a car's dashboard and use Compass or Maps, do not wave the device in a figure 8 to calibrate. Instead, mount iPhone 3G S, open Compass or Maps, and disregard the message to calibrate. iPhone 3G S will eventually re-calibrate after several turns.
 

BigOrangeSU

macrumors regular
Dec 22, 2008
218
1
How come my google maps isn't showing the direction I am pointed? I thought that was a feature

edit: NVM tap the location button twice
 

timotheezz

macrumors regular
Jul 6, 2007
145
1
New Jersey
How to RE-calibrate?

Yes mine worked after I calibrated it.

I've read a few threads here about the compass being inaccurate. I, too, have been having issues. In maps, my location is accurate, my the direction I'm facing is like 45 degrees off.

After the initial calibration I have not been able to get the option to calibrate again. Does anyone know how to re-calibrate?

It's very minor, I know. But it's just frustrating.
 

avaloncourt

macrumors 65816
Oct 18, 2007
1,315
0
Sorry...but just metal should not interfere.... Now maybe there are some electronics or an in-car compass that is interfering....but not the frame of the car.

:confused:

Apparently you don't know anything about magnetism, magnetometers or compasses. Do some research into magnetic deviation related to a compass. All boats that rely on a magnetic compass for navigation have a deviation table plotted for all points around the compass. The amount of error will be different in any particular direction. The table allows you to correct for the deviation.

A car not only has a shell of metal and a frame of metal but also a huge hunk of metal called an engine. That engine also has an alternator attached that creates it's own magnetic field. ALL of these things will interfere with the proper use of a compass. Turn off the car and you'll still have problems (electronics eliminated). Get out of and step well away from the car and the problem disappears.

The calibration will help within the car but once outside of the car it will no longer be calibrated because the same forces affecting it for the calibration are not involved.
 

BrownManUPS

macrumors 6502a
Jul 30, 2007
824
25
Denver
I don't even get the figure 8 motion...what is going on with that?

I still don't know how to get it to work in the car. I tried waiting and it does it sort of in the background but not as great as it could be (and is very wobbly)
 

flapperdink

macrumors member
Jan 25, 2009
80
0
I don't even get the figure 8 motion...what is going on with that?

i too am really curious on what we are exactly doing when we move it in the figure 8 motion. being an electrical engineer i admit i am very nerdy with these types of electronics, but i can't come to a conclusion on what we are actually doing when we do that. i was thinking that a gyro-type device is used in conjunction with the magnetometer, but i don't see any way how moving it in a figure 8 motion is tied to a magnetic-only device. :confused:
 

kdarling

macrumors P6
i too am really curious on what we are exactly doing when we move it in the figure 8 motion.

My Grand Cherokee required that I drive in a circle three times to calibrate its onboard compass.

From what I can tell, magnetometer makers have proprietary algorithms for self-calibration that you can license and use in your OS code.

My guess is the figure-8 is used to average out any magnetic anomalies around you.
 
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