Garmin 20x variation

[Scorpanicus]

Just getting familiar with a Garmin 20x.

 

I know that the unit automatically calculates variation depending on where you are (variation is around 24 degrees here) but I cannot find anywhere in the menu that actually shows what the current variation is. In my old Etrex (about 12+yrs)the variation was shown under 'Units' in the menu.

Is the actual variation amount indicated anywhere in the 20x or is that no longer a feature?

[+The A-Team]

Just getting familiar with a Garmin 20x.

 

I know that the unit automatically calculates variation depending on where you are (variation is around 24 degrees here) but I cannot find anywhere in the menu that actually shows what the current variation is. In my old Etrex (about 12+yrs)the variation was shown under 'Units' in the menu.

Is the actual variation amount indicated anywhere in the 20x or is that no longer a feature?

Do you mean "declination", as in the difference between true north and magnetic north for a given location?

 

I haven't used either an old or new version of eTrex before, so I can't answer whether you can view the current declination. I have the Oregon 450 and 600, both of which use roughly the same software as the 20x, and I don't think either show the declination.

[+HHL]

[...]

Do you mean "declination", as in the difference between true north and magnetic north for a given location?

[...]

I guess this is meant:

Garmin Glossary (click here)

Magnetic Variation

In navigation, at a given place and time, the horizontal angle (or difference) between true north and magnetic north. Magnetic variation is measured east or west of true north.

 

Hans

[Scorpanicus]

Do you mean "declination", as in the difference between true north and magnetic north for a given location?

 

I haven't used either an old or new version of eTrex before, so I can't answer whether you can view the current declination. I have the Oregon 450 and 600, both of which use roughly the same software as the 20x, and I don't think either show the declination.

 

I mean magnetic variation - being the difference between True and Magnetic north. (useful for adjusting a separate compass for use on a paper map.)

In the old 'yellow' Etrex, under 'Units' this was given in the 'Variance' window. Can't seem to find it anywhere on the 20x.

[Scorpanicus]

I've just contacted Garmin support re' the query.

Apparently the Etrex 20x does not have the feature that shows the degrees of variation. Bit of a backward move.

[+The A-Team]

[...]

Do you mean "declination", as in the difference between true north and magnetic north for a given location?

[...]

I guess this is meant:

Garmin Glossary (click here)

Magnetic Variation

In navigation, at a given place and time, the horizontal angle (or difference) between true north and magnetic north. Magnetic variation is measured east or west of true north.

 

Hans

Interesting. Upon looking into it further, it seems that "magnetic declination" and "magnetic variation" are equivalent terms. I had only ever heard the term "declination" used. Must be a regional thing.

[Scorpanicus]

A Team

Interesting. Upon looking into it further, it seems that "magnetic declination" and "magnetic variation" are equivalent terms. I had only ever heard the term "declination" used. Must be a regional thing.

 

Hi,

There is a definite difference between variation and deviation.

'Variation' is the variation in degrees (east or west) between true north and magnetic north.

'Deviation' is the deviation (error) in degrees in any particular compass, also east or west. This deviation can be different in different compasses or even when on different headings. A ship's fixed compass in particular can be subject to 'deviation' because of the metal surroundings. So adjustments have to be made either to the compass or to the bearing to compensate for this deviation. So consideration has to be given to both variation and deviation in those cases.

Edited November 10, 2016 by Scorpanicus

[+fizzymagic]

There is a definite difference between variation and deviation.

'Variation' is the variation in degrees (east or west) between true north and magnetic north.

'Deviation' is the deviation (error) in degrees in any particular compass, also east or west.

 

The word in question is "declination," not "deviation."

 

AFAIK, variation and declination are the same thing.

[+fizzymagic]

I've just contacted Garmin support re' the query.

Apparently the Etrex 20x does not have the feature that shows the degrees of variation. Bit of a backward move.

 

Why do you think this feature belongs in a GPS? It's easy to look it up in a table, which you should have already done if you are using a compass.

 

Magnetic north has no relevance to GPS navigation.

[+GeoTrekker26]

I've just contacted Garmin support re' the query.

Apparently the Etrex 20x does not have the feature that shows the degrees of variation. Bit of a backward move.

 

Why do you think this feature belongs in a GPS? It's easy to look it up in a table, which you should have already done if you are using a compass.

 

Magnetic north has no relevance to GPS navigation.

 

Would it be useful if the GPS has a 2 or 3 axis electronic compass?

[Scorpanicus]

Why do you think this feature belongs in a GPS? It's easy to look it up in a table, which you should have already done if you are using a compass.

 

Magnetic north has no relevance to GPS navigation.

 

Convenience and confirmation I guess. It was on my old Etrex. There are a swag of new features on the 20x, some that I probably won't use, but that one has been removed. Some of my maps are quite old now and the variation has 'crept' since they were printed. (requiring an annual calculation.) I just like to use the gps occasionally to get a bearing on a point and then turn it off and use a compass/map. The compass I use has a manual adjustment for variation which means less 'mental arithmetic' when working off a map section.

You're right re' variation and declination, they are the same thing - my mistake. Sorry,I went off on a tangent and started rattling on about 'deviation'.

[+HHL]

[...] The compass I use has a manual adjustment for variation which means less 'mental arithmetic' when working off a map section.[...]

 

Garmin's magnetic compass is adjustable as well: Settings > Compass > User (instead of true or north)

 

Hans

[+EScout]

The declination or variation can be determined for your area by doing this: with your heading in settings set to true north, look for a way point you have saved a couple miles away. It will show distance and bearing to it. Change your heading to magnetic and look up the same way point. Subtract the magnetic bearing from the true one. This will give your variation, and if the number is positive, it is an east variation.

[Scorpanicus]

The declination or variation can be determined for your area by doing this: with your heading in settings set to true north, look for a way point you have saved a couple miles away. It will show distance and bearing to it. Change your heading to magnetic and look up the same way point. Subtract the magnetic bearing from the true one. This will give your variation, and if the number is positive, it is an east variation.

 

Hi EScout. Yes, I'd realised you were able to do that. Just seemed a more convuluted way about finding it after being able to use the direct 'variance' feature on the old Etrex. I just wondered if the feature was still there somewhere on the 20x but I couldn't find it!

Thanks for all the replies.

[+JohnCNA]

Why do you think this feature belongs in a GPS? It's easy to look it up in a table, which you should have already done if you are using a compass.

 

Magnetic north has no relevance to GPS navigation.

I have run into a couple Puzzle or Multi caches that used a field projection using magnetic instead of true bearings. Smartphone or internet access are not always available when you need them. It could be handy to have that option built in when it's needed.