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Elevation And Clock Off On Magellan


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Try this, go to the Position screen press menu

and go to elevation mode press enter and choose 3D..

good luck . I have the SporTrak Map

Thanks for the suggestions but it's been in 3d mode since day one. Made sure it was again after the reset.

I'll wait till I'm out in the field today and check the clock and elevation again. If they don't work right then it's a call to the shop and see about sending it in. I've only had the unit for four months. :lol:

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The error on the vertical (the elevation) of a GPSr position is about 150% (or more) of the error of the horizontal - ie. if there is a 10 meter error in the horizontal, it's safe to assume that there could be a 15 meter error in the elevation. This is true in all GPS units, including $70,000 survey grade systems. Elevation is the weak point. With my handheld, I've seen fluctuations of over 100 feet at any given point.

 

An elevation difference of 20 feet is probably nothing to worry about. Think of it like this, you could visit a cache and the coordinates could be right on. You could re-visit the cache at a later day or time and the coordinates could be 20 feet away. Your coordinate just moved up instead of sideways.

 

The time that is set on a GPSr is sent from the GPS satellites so it is in synch with the satellites. If it is off, you may be having a firmware issue (which you already reloaded) or a processor issue, which would require service. It could be that the clock that you're checking it against is off too.

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An elevation difference of 20 feet is probably nothing to worry about. Think of it like this, you could visit a cache and the coordinates could be right on. You could re-visit the cache at a later day or time and the coordinates could be 20 feet away. Your coordinate just moved up instead of sideways.

 

The time that is set on a GPSr is sent from the GPS satellites so it is in synch with the satellites. If it is off, you may be having a firmware issue (which you already reloaded) or a processor issue, which would require service. It could be that the clock that you're checking it against is off too.

Out in the field today going after my :P 100th :P cache I got 9 of nine. The clock is now working ok so that must have been the firmware having a bit missing. As for the elevation, at times it seemed to be really close to three other receivers but never right on with another brand new one (same brand/model). I had a chance to test it against some surveyers one day and it was within 3 feet. I'll do some more testing but I have a feeling there is something amiss with the unit.....

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My Magellan SportTrak Map has been showing the time 4 minutes slow and the elevation about 20 feet or so low. I did a clear of the system, re-installed the 5.0 firmware then started it up. I set the clock which seems to be working ok at this time but now the elevation is showing a big fat goose egg.

 

Anyone know of this problem before??

You set the clock? I've never heard of a GPS where that's possible. You can usually change the offset, but a manually set time would be useless to a GPS.

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You set the clock? I've never heard of a GPS where that's possible. You can usually change the offset, but a manually set time would be useless to a GPS.

On Meridian and I think Sportrak, you set the display time (not GPS time) at initialization. This gets adjusted automatically when the receiver gets a lock. Due to some software problem, perhaps related to how accurately the time is initialized, this adjustment is done wrong on some units. My Merigreen displayed time that was 3m42s slow. Resetting the time it did no good, as every time it got a lock it re-adjusted to the same 3m42s slow. As Rosco found out, the cure is to reinitialize the unit. It may be that at initialization the time must be set manually within a minute or two of the correct time.

 

There are old threads on this subject, which I'm too lazy to dig up.

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You set the clock? I've never heard of a GPS where that's possible. You can usually change the offset, but a manually set time would be useless to a GPS.

On Meridian and I think Sportrak, you set the display time (not GPS time) at initialization. This gets adjusted automatically when the receiver gets a lock. Due to some software problem, perhaps related to how accurately the time is initialized, this adjustment is done wrong on some units. My Merigreen displayed time that was 3m42s slow. Resetting the time it did no good, as every time it got a lock it re-adjusted to the same 3m42s slow. As Rosco found out, the cure is to reinitialize the unit. It may be that at initialization the time must be set manually within a minute or two of the correct time.

 

There are old threads on this subject, which I'm too lazy to dig up.

There were some posts on the Yahoo Meridian user groups that said if you reinitialize the unit and set the clock 20 minutes off it would get corrected to the right time after recieving sat signals.

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this may be a dumb question but can you actually view the gps internal clock? my display clock/date has to be adjust for a 'non-standard' time zone upon reset but if left alone it will gain lock but the display will be off until i correct it. i believe the gps uses the display time to help find itself by limiting it sat search pattern based on the previously loaded almanac but will adjust itself when it gains the current almanac. in any event specficing date/time/location geatly speeds up the iniatilization process.

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I wrote to Magellan support and I'll see what they say. If they say.........

I thought you had solved that problem. Re-initialization is the answer.

 

Here's the email I got from Magellan back in April when I wrote them:

 

I might suggest resetting the unit to correct this issue.......................or perhaps updating software may be in order.............try resetting first and re-initialize first

 

Turn on the unit again and clear memory (waypoints and routes will be lost) by pressing MENU from any screen, select 'Setup', 'Clear Memory', then select 'All' and 'Yes'. The unit will turn off automatically.

 

Make sure the unit is off. If you are not sure, remove batteries then reinstall the batteries. Press and hold the MENU key then press and hold the POWER key. The unit powers up and the 'Clear all memory?' message comes up. Select 'Yes' and press ENTER and the unit will clear memory and turn off automatically.

 

Regards John Valencia

 

Thales Navigation

960 Overland Court

San Dimas, California 91773

USA

(800) 707-9971

(909) 394-5000

www.thalesnavigation.com

www.magellangps.com

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The clock only tells/shows you the time, nothing more. Has no affect on the accuracy either horizontal or vertical. A unit that ignores time (as in time of day etc) from the nav message does have a problem though as it really should update the time on a reasonably regular basis but not being a mission critical value doesn't waste rescourses in doing this either.

 

Some receiver clocks can be off by as much as few seconds anyway and actually 3m 42 seconds is quite interesting in some respects.

 

Cheers, Kerry.

Edited by Kerry.
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I don't know wether it's been fixed in the new firmware.

Nope. I guess it is not fixed until now. Its not a Sportrak problem, its a Magellan problem. This bug also exists in the Meridian series.

Even with software version 5.12 on my MeriGold the problem still exists. I simply ignore it. I doesn't affect anything else.

Wulf

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