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Thot

Is the compass on a 64s worthless?

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I have chased this issue for 3 years.

 

I have a friend who assures me the pointer should continue to point to the cache even when standing, still if the compass is calibrated.  This is not my experience.

 

After my thread here and discussions with two others who have this unit I concluded my unit must have a flaw and ordered another.

 

The compass is calibrated in both the videos below.  I'm in my 80s and have tremor.  In the following videos I am still (not moving) and the GPSr is still.

 

 This is how my original unit was behaving. The pointer and the compass arrow jumped while I was still.

Well, this is how the replacement unit is behaving .  As you can see there is no change. The conditions for the videos were identical. Except for my tremor I and both units were still.

So I bought a replacement for nothing. What the hell is the compass suppose to do? It doesn't point north (at least the arrowhead with an N doesn't) and doesn't stabilize the pointer when stopped. This board doesn't seem to provide for images so you have to go HERE to see what I mean by the arrowhead.  And HERE if you think I don't have the compass turned on.

 


 

Edited by Thot

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That’s not a compass, that’s Jim, and if the map is in track up mode, it’s suppose to point where Jim is facing, yes.

That may not be the cache.. Only if you are actually facing the cache.

If the map is in north up mode, it should always be oriented so the map is north at the top of the screen, but Jim can still change direction on the map.

 

I have doubt the compass you had as a young boy would work well in a car. Have you tried at home?

It sounds like you doubt this works: 

 

Edited by _Art_

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I don't own a 64, but I used a 62s for most of my caching life (replaced it with an Oregon 700 last year) and the compass does need to be regularly calibrated, particularly after changing the batteries. The batteries themselves are often magnetised to varying degrees so that needs to be calibrated out each time they're changed, otherwise I found the compass would be quite erratic. You also need to do the calibration well away from anything else that might disturb the Earth's magnetic field, like any iron or steel objects. And make sure you're not wearing a wristwatch that might itself be magnetic.

 

Another factor that I'm not sure about, but my observations suggest that when the device detects that it's moving, which it does by looking at changes to your coordinates, it uses the direction of movement to override the magnetic compass. So if GPS reception is poor, or if it suddenly changes because the receiver has locked onto an additional satellite (or lost one), causing its perceived location to change, that could conceivably cause a sudden jump in the compass direction until it all settles down again.

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GPS drift is the reason Garmin are quoted to have given in the thread linked by the OP,  and what I think most likely.

I’m not so sure it was understood in that conversation though.

 

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I almost never use the compass on my Oregon 600 but although it probably has nothing to do with the TS' problem it's worth keeping in mind that Magnetic North is not pointing to N90°. It may not make a big difference in many place but when on holiday in Greenland magnetic North was NW of us or about 30°(West) off from "true North". Where I live it's only 1° (East) off.

Magnetic North is drifting toward Siberia at a rate of 55 Km/year now for the last few years, it used to be only a few Kilometers/year a few decades ago.

Check your magnetic declination here.

 

We're heading for a magnetic switch soon  (probably within a few 100 years), then the magnetic North will be in the Southern hemisphere as his was several times before. More here

 

 

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True North is an option in the Satellite page, but I don’t know how a 64 could get that information dynamically.

It’s maybe just a constant that is updated with firmware.

 

 

 

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It’s not the tremor by the way. Didn’t think to try it before, but you could have a full on fit much worse than you’re doing and it’s fine. Anyone with a 64 can try it.

 

Edited by _Art_

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9 hours ago, Thot said:

I have chased this issue for 3 years.

 

I have a friend who assures me the pointer should continue to point to the cache even when standing, still if the compass is calibrated.  This is not my experience.

 

After my thread here and discussions with two others who have this unit I concluded my unit must have a flaw and ordered another.

 

The compass is calibrated in both the videos below.  I'm in my 80s and have tremor.  In the following videos I am still (not moving) and the GPSr is still.

 

 This is how my original unit was behaving. The pointer and the compass arrow jumped while I was still.

Well, this is how the replacement unit is behaving .  As you can see there is no change. The conditions for the videos were identical. Except for my tremor I and both units were still.

So I bought a replacement for nothing. What the hell is the compass suppose to do? It doesn't point north (at least the arrowhead with an N doesn't) and doesn't stabilize the pointer when stopped. This board doesn't seem to provide for images so you have to go HERE to see what I mean by the arrowhead.  And HERE if you think I don't have the compass turned on.

 


 

 

The GPSMAP 62s is a very capable unit, and you have two of them! (that's two more than I have right now, the 62 and 64 I still need to acquire)

 

The unit appears to be functioning correctly, so far as I can determine.

 

The 'jumping' north direction in your first videos is common when the unit is placed inside a huge faraday cage. (the vehicle you are sitting in)

 

Try calibrating the compass again once you have exited the vehicle. Although your Garmin GPSr is not an Oregon 6x0, there is some excellent/applicable compass information available at GPSrChive > Oregon 6x0 > Applications > Compass and Setup > Heading:

 

Always calibrate the compass outdoors, away from objects that influence magnetic fields (cars, buildings, power lines)

  • After moving long distances
  • After experiencing significant temperature changes
  • After replacing the batteries

 

 

As for the images of the North Arrow on the Map Page, that also appears to be functioning exactly as designed. You clearly have the Map set to 'Track Up'. You can change that to 'North Up' by selecting (from the Map Page) Menu > Map Setup > Orientation > North Up.

 

If you like, post your concerns to the GPSMAP 62 discussion forum found here.

 

Edited by Atlas Cached

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4 hours ago, _Art_ said:

That’s not a compass, that’s Jim, and if the map is in track up mode, it’s suppose to point where Jim is facing, yes.

That may not be the cache.. Only if you are actually facing the cache.

If the map is in north up mode, it should always be oriented so the map is north at the top of the screen, but Jim can still change direction on the map.

 

I didn't follow that but, I understand track up mode -- I've been using it for 15 years.  At first the pointer was pointing to the cache in both cases.

 

As for calibration, both units were calibrated after the last battery change and within an hour before the videos were made.

 

The comments about being in the car seem valid, but the reason I did these tests is because when in the field the original unit would never continue to point to the cache when I stopped moving and this has been happening since I got the unit. 

Edited by Thot

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1 hour ago, Thot said:

the original unit would never continue to point to the cache when I stopped moving and this has been happening since I got the unit. .......   At first the pointer was pointing to the cache in both cases.

That’s a strange way to describe the issue. It’s never trying to orient the map screen to face the destination. That only incidentally happens if you are walking toward it.

 

The actual compass screen can do that. 

 

I’m wondering what happens if you spin it about on a desk slowly like that, even if you are shaky.

 

Edited by _Art_

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7 hours ago, Thot said:

I didn't follow that but, I understand track up mode -- I've been using it for 15 years.  At first the pointer was pointing to the cache in both cases.

 

If the 'Pointer' on the Map Page (North Arrow) was actually pointing toward the geocache, is was only because the geocache was North of your current location, and was purely coincidental!

 

 

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7 hours ago, Thot said:

The comments about being in the car seem valid, but the reason I did these tests is because when in the field the original unit would never continue to point to the cache when I stopped moving and this has been happening since I got the unit. 

 

"the original unit would never continue to point to the cache" is too vague to understand. There are too many possibilities here. The "original unit" could refer to anything, including the Quad Helix antenna, the bearing pointer in the actual Compass Page, the pointer in the Geocaching Dashboard, or the North Arrow on the Map Page.... and many others....

 

WHAT EXACTLY "would never continue to point to the cache when I stopped moving"????

 

 

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While everyone else figures out what you mean, I'll offer another solution to test whether your compass is actually working.
 

  1. Go outside with your GPS - fresh batteries, open location, not your car. Cars will mess with the compass causing it to not point the right direction.
  2. Switch over to the compass page. Don't navigate to a cache or any other waypoint. Just go to the compass page.
  3. Calibrate your compass.
  4. While on the compass page, spin around in place. Not too fast. Does the compass spin with you?
  5. Face a known direction (IE, if you know which way north is, face north). Does the compass say you are facing that direction?
  6. Start walking in a straight line. You'll need to walk at a moderately brisk pace, like you're walking with intent, for the compass to swich to using your movement to determine your heading. Does the compass change direction significantly between walking and moving?

Do that and reply with the answers to those questions and we can then start to determine whether the problem lies with your GPSr and not some user error.

Some other things that might be throwing off the navigation: Do you have a routable map installed (OpenStreetMap, a Garmin state topo, or City Navigator)?
Is your routing method set to "Direct?"  And is Lock on Road set to OFF?. 

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Just an observation after owning a couple of different generations of Garmin  units with the magnetic compass feature...

 

First, the fact that calibration is in any way related to battery voltage is a design sin in my book.  The chips that provide the compass function are typically spec'd as operating within a 2.16 ~ 3.6V supply range.  I've looked at all of the usual suspects in the past (most of them Honeywell ASICs) and nowhere do I ever see any internal supply voltage regulation.  Since voltage developed across the magnetoresistive sensors is impacted by the supply voltage, one would therefore assume that the supply voltage must itself be regulated to produce a consistent result.  If I've had this right based upon a lot of field experience (large shift in compass results with cell voltage), Garmin has never provided a regulated supply voltage to these chips, so any variation in what the cells produce is reflected in the digital output of the ASIC.  Not good.

 

That said, I've had my best luck by NOT calibrating with a freshly charged set of cells.  That's often when they're looking very 'hot', fresh off the charger, and produce a voltage that won't be seen for very long, and won't be seen again through the duration of the use of the cells.  Instead, if I calibrate at all, I'll wait for half an hour or so of use until the cells settle down to something more typical of the voltage they'll be providing for most of the time they're in use before the next charge.  So for the first few minutes of use, they'll be 'hot', and the compass will be a little wonky, but that doesn't last long.  And towards the very end of the time those cells are in the device, the compass will be a little wonky as well.  I change them out as soon as I reach that point.  By calibrating somewhere in the more normal operating range of the cells, I get a more useful compass result through the duration of use of those cells before recharging them.

 

 

 

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