Dear Dr. Cache

[Guest Choberiba]

My Vista has a built in digital compass.

 

When projecting waypoints three points out, I get a result that differs from what the cache owner is claiming.

 

example:

 

Start at the waypoint given on www.geocaching.com

 

Head .88 miles at a bearing of 111

Head .77 miles at a bearing of 222

Head .66 miles at a bearing of 333

 

Start looking for the cache.

 

According to the owner, my yellow eTrex is giving results that are more in line with his, even though the eTrex is limited to tenths of a mile when projecting.

 

Is the compass a factor in the discrepancy, or is my ex-wife messing with my head again?

 

Inquiring minds and all that.

 

Thanks, Eric.

[Guest sjdavis]

I have a simular issue with my Vista.

On the map page i can get the arrow over the cache, but my compass sends my about 30 ft away. This is out side the accuracy circle.

I will be watching this post.

 

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[Guest sjdavis]

I have a simular issue with my Vista.

On the map page i can get the arrow over the cache, but my compass sends my about 30 ft away. This is out side the accuracy circle.

I will be watching this post.

[Guest arffer]

What does the cache owner want you to have your compass set to; True North or Magnetic North? What do you have your compass set to? Do they match?

 

This will cause major discrepancies.

[Guest TeamCNJC]

quote:

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Originally posted by Choberiba:

When projecting waypoints three points out, I get a result that differs from what the cache owner is claiming...

 

According to the owner, my yellow eTrex is giving results that are more in line with his, even though the eTrex is limited to tenths of a mile when projecting.

 

Is the compass a factor in the discrepancy, or is my ex-wife messing with my head again?

---

 

If the eTrex is limited to 10ths of a mile when projecting, the owner probably used something else to create the waypoint projections. I would skip the compass function of the Vista altogether, and use the waypoint projection function, both in true and magnetic modes, or use G7toWin to map out the projections. -Craig

 

PS - do you have the cache name/ID?

 

[This message has been edited by TeamCNJC (edited 09 October 2001).]

[Guest Choberiba]

Thanks for the suggestions regarding True/Magnetic North.

 

I had manually shut the compass down on the second reading and the results were identicle as the first reading. Is the compass never truly off?

 

quote:

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Originally posted by TeamCNJC:

PS - do you have the cache name/ID?

---

 

Yes, but I'm intentionally leaving it out since that might spoil some of the surprise for future cache seekers. Feel free to email me for furthur specifics on the cache itself.

 

I am comfortable with offering that it's more than a hop-skip-jump from Maple Grove.

[Guest Reservoir Dog]

test update? Further, I feel the compass, because of it's sensitivity, should only be used while not under defilade. In fact, I think it would be a good idea to use the map all the time.

 

I Look forward to your comments.

 

[Guest TeamCNJC]

OK, I tried this using my Venture.

 

I started in your neck of the woods at N38 W122, and projected a waypoint 4.56 miles at bearing 123. My heading was set to true, as indicated by the "t" under the degree sign. I then switched to magnetic mode, and projected a new waypoint from the initial waypoint. The magnetic waypoint N37 57.050 W121 56.658 was 1.21 miles from the true waypoint N37 57.844 W121 55.793. Check to see how the eTrex was set (magnetic vs. true), then set your Vista the same way. Ignore the compass and project away! -Craig

[Guest Prime Suspect]

quote:

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Originally posted by Reservoir Dog:

The words "hold level" appear on the screen below the compass when it isn't level and disappear when it is. When I used this new(?) feature and held it level, the azimuths were within 1 degree of each other.

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This is not a new feature, since the ability to detect if the unit is being held level requires built-in hardware. You should find the "hold level" display mentioned in your manual.

[Guest Choberiba]

quote:

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Originally posted by arffer:

What does the cache owner want you to have your compass set to; True North or Magnetic North? What do you have your compass set to? Do they match?

---

 

Originally the Vista was set to true North, Changing it to magnetic North seems to give the desired results.

 

Before figuring this tid-bit out I took another stab at it, using the standard eTrex.

 

I forgot my regular compass and ran out of time so it wasn't successful, but someone smashed the window of my car in, so the day wasn't a total loss.

 

Oh Yeah, Happy birthday to me.