Atomic Cobalt compass problems

[RonR]

After 32 dives with no problems from my Cobalt, the compass went wacky on me this Sunday. ...
Any ideas?

If you have been careful to calibrate accurately and away from ferrous metals (which it sounds as if you have been) then it seems that something has caused the internal constants to no longer be correct for the chip- that would explain the seemingly random errors. We have confirmed that this can happen after exposure to strong magnetic fields, but frankly we don't understand why the chip should change sensitivity otherwise. In these cases a more involved calibration process has brought back the function by resetting the gain and offset for each axis of the chip. I've made up a detailed instruction sheet for this "six point" calibration, PM me with an email and I will send it to you. It's the procedure used at the factory to set up the compass initially. It was taken out of the normal user menus because we didn't think it would be necessary- but we may end up putting it back in because it does seem some people are experiencing this issue.

Ron

[skyjester105]

I too, have had a problem with the compass. I've even sent it back for repair already. It indicated some of the same issues that others have had, namely somewhat accurate North and South, only shows East even when pointed West.

When I got the computer back from repair, I noticed that the compass calibration page had different settings. However, when I changed some of the personal settings, these pages went away.

My questions; what are these pages for, where did they go, and could they mess up the compass adjustments for the "normal 3 step alignment" and make the compass unstable or hard to align.

Thanks,

Brian

[RonR]

I too, have had a problem with the compass. I've even sent it back for repair already. It indicated some of the same issues that others have had, namely somewhat accurate North and South, only shows East even when pointed West.

When I got the computer back from repair, I noticed that the compass calibration page had different settings. However, when I changed some of the personal settings, these pages went away.

My questions; what are these pages for, where did they go, and could they mess up the compass adjustments for the "normal 3 step alignment" and make the compass unstable or hard to align.

Thanks,

Brian

I'm not 100% sure what you are referring to as the compass calibration page- in the six point calibration mode there is a diagnostic / informational page that displays the calibration constants for the chip just after you access the menu item. Is that it? If you sent it back for recalibration those values might well have changed. If you then changed the user name, it would have gone out of calibration mode into end user mode, and that page would no longer appear. You would no longer see the option for six point calibration, HP sensor calibration, or that page. It wouldn't cause any problems, it's normal.

The six point calibration sets the gain and offset for the chip on all three axis (3 x 2 = 6, hence six point). These constants need to be set correctly in order for the normal three point calibration to work. They don't replace the three point "normal" calibration, you still need to do that when moving from one geographic place to another. What we have seen is that some circumstances- such as exposure to strong magnetic fields- can cause the compass chip to change its sensitivity such that it needs to have that six point calibration redone. The kind of errors you describe are what might appear if the six point calibration was no longer correct. Hopefully it is correct now, and a three point calibration will have the compass reading accurately.

We are considering if we should put the six point calibration option back into the user menus. It's more involved that the normal calibration, but if the chip has been altered by some environmental exposure (we have had reports of their happening after air travel, and suspect some security equipment) it requires the six point, followed by a three point calibration to get it back to reading correctly. Theoretically (at least according to the chip manufacturer) this should only need to be done once, at the factory. But we do see examples in the field where it the chip has changed sensitivity such that it needs new constants.

Hope this isn't confusing- bottom line is that you should be fine doing a three point calibration. Your compass should read with reasonable accuracy in any position, as it is fully tilt compensated.

PM me with an email if you want the full instruction set for doing the six point calibration and accessing that mode.

Ron

[skyjester105]

Yes, the 6 point calibration is exactly what I saw. After getting the computer back and doing the 3 point, again, away from all metal etc., my North and South are close but the east and west are way off (60 degrees or more). absolutely abysmal for an electronic compass.

How do I reset the computer to the 6 point calibration page and how is the calibration done, please.

Brian

[RonR]

Yes, the 6 point calibration is exactly what I saw. After getting the computer back and doing the 3 point, again, away from all metal etc., my North and South are close but the east and west are way off (60 degrees or more). absolutely abysmal for an electronic compass.

How do I reset the computer to the 6 point calibration page and how is the calibration done, please.

Brian

PM me with your email and I'll send the PDF instructions. The compass is not super accurate, but should be good to within 5° or so. Let me know what version of the firmware you have- in recent ones we show the calibration constants. That could be helpful in determining if there is a problems with your chip, or if something is knocking it out of range.

Be careful of hidden metal in tabletops- I found I can't calibrate on part of my kitchen counter because the dishwasher motor has a magnetic field that throws it off.

Ron

[skyjester105]

Ron,

Thank you for all your help here on line.

I stopped by my local dive shop and pleaded for help. They had the instructions for setting up the unit for the 6 point calibration. It all worked fine in the "UP-DOWN" orientation and in the "FACE UP-FACE DOWN" axis. However, no matter how we tried, we could not calibrate the "Y" axis. Definitely a flipped out flux gate. We tried in the middle of the floor in the showroom, in the classroom, and finally in the workshop that has wooden work tables to no avail.

This is when you excellent customer service kicked in and I walked out of the shop with a replacement unit.

Thank you to everyone in helping me with this issue.

Brian

[RonR]

Ron,

Thank you for all your help here on line.

I stopped by my local dive shop and pleaded for help. They had the instructions for setting up the unit for the 6 point calibration. It all worked fine in the "UP-DOWN" orientation and in the "FACE UP-FACE DOWN" axis. However, no matter how we tried, we could not calibrate the "Y" axis. Definitely a flipped out flux gate. We tried in the middle of the floor in the showroom, in the classroom, and finally in the workshop that has wooden work tables to no avail.

This is when you excellent customer service kicked in and I walked out of the shop with a replacement unit.

Thank you to everyone in helping me with this issue.

Brian

Did they have the complete photo instructions or just the written instructions? Some have misunderstood the Y axis instructions so we added another sheet with photos for clarification. If you can let me know who the dealer is I'll make sure they have the complete set.

Glad you got it taken care of in any case.

Ron

[skyjester105]

We had only the printed version so the photo sheet would help. We did have a tech rep on the phone at the time, so I think we were well cared for.

I was working with the good folks at Aquatic Adventures, Inc. in Brookfield, WI.

Thanks again,

Brian