GPS compass north

Using Garmin GPS compass with Blue charts, what is the correct choice for North ?

True, magnetic, or Grid ?

For what purpose?
If you don’t understand how to answer that question, then grid will be the correct choice for you.

go to ?
The usual: go to waypoint, follow route. Establish track.

GPS screen has a arrow pointing to waypoint, route path. The arrow is dependent on what is north or not ?

Or is the arrow independent of North ? Triangulated by GPS software to the waypoint independent of Grid/Magnetic/True ?

If this latter is true…then what is the compass function ? With GPS is the compass an appendix ?

I don’t know. Maybe I’m GPS compass ignorant ? I read the book .

I traded a 76 for a 78 arriving last week so I’m relearning Garmin speak. Trying to…

Then it doesn’t matter in the least
Just go where the arrow points you.

The settings are only relevant if you are using paper charts.

Magnetic if you are using a compass
Best to go back to the manual and Google, and read up on this until all the options make sense. Then you can pick the best option for your needs.

I generally have north set to magnetic on my GPS so that I can use the bearing shown on the GPS to navigate via my deck compass. This allows me to turn off the GPS to save batteries. I turn on the GPS during breaks to ensure I’m still on course. Even if I have the GPS on I usually prefer to use the compass on a long crossing since following the GPS arrow will often have you over-correcting and zig-zagging like a drunken sailor. Better yet, while on course, find a cloud or other object on the horizon and follow that, and then find another when necessary. That will often yield a better course than being “heads down” on either GPS or compass.

A GPS can die at any moment. On any major trip or long multi-day race I carry two GPS units and also carry compass and charts.

As MintJulep said, if you are just following the pointer for a route or to a waypoint then the arrow points to your destination or next leg (and not true or magnetic North) so it doesn’t matter what the north setting is on your GPS.

Greg Stamer

Grid north and true north should
fairly close to each other. It has to do with trying to represent a sphere on a flat surface. Magnetic north is where the earth’s magnetic poles are located which can give you quite an error if not considered. On the west coast it’s 16 degrees. I adjust the declination on my compass so it always points to true north. It’s easy to make a mistake if you don’t adjust your compass for declination since you have have to do the math in your head and use the east is least, west is best aid helping you remember to subtract or add to adjust to true north depending on your location.

I deleted my answer which took your
nonsense out too.

You can post it again with out my being in the loop.

Jack L

Look up USNG
I would also suggest you look up the US National Grid System (same as MGRS) on the USGS web site. They have some good tutorials on what is grid, magnetic north and more importantly declination. I have used their material to teach several classes and it is well put together. All the information can be hard to understand so I would also suggest to physically sit down with someone who has a grasp on this to help you, someone that was in the Infantry would be my suggestion. These aren’t really questions that can be explained through a forum string. Anyone that I have taught has had that moment when it all clicks and they understand but it is different with everyone. That’s why I recommend actual human contact.

This link is where I’ve gotten my information.


Google sez the DOI geoaddress is the Sears Tower in Chicago ?


Sears Tower 1 10 NW 10 State Street AVE NW 100 …

Houston ?

Garmin Homeport ?

So far, Homeport rejects NAD83 18SUJ22850705 as invalid input. Suggestions ?

Try a road map

– Last Updated: May-17-14 12:42 PM EST –

It appears that you are trying to mesh the grid results in one system with navigational charts that go with the Garmin, if I scan all of the above.

So you are trying to paddle in a kayak to the Sears tower in downtown Chicago, guided by Garmin blue charts.

Either your Garmin is attempting to tell you that the Sears tower is not in the lake, or it just needs different prompts so you can add wheels and turn signals to your kayak to get there. Perhaps a seat belt too.

It is of course possible that I misunderstand. In fact given the clarity of your posts it is likely.


The USNG site is new here and interesting for us.

The Dept of The Interior (DOI - Dead On Insertion) UTM when Googled offers the Sears Tower.

Homeport nor Mapsource on the PC accepts UTM here…the handheld’s program does last I tried several years ago.

The Sears Tower search is interesting to the man on the street as an example of the available information packet.

Does Celia work for Paddlenet ?

I am just messing with you. In English rather than some of the others…


Posting into kayak discussion groups is open ended.

Both spectrum ends are entrenched in their endorphins…th Ol’ Salt, The Expert, The Adventourer, The Hi Flying Newbie.

Difficult telling if you are illiterate, ignorant, violent, perverted or merely un-articulate.

We unfairly judged you as merely stupid.

two of my well meaning posts into Wet Coats Neanderthal Kayaking were discarded. One the MSR Keel bag project, a techno advance, and the double float practice suggested to an alleged beginner.

Go figure right ?

I take it you have a map or a chart
If so…and no serious paddler relies on GPS exclusively… there is a gizmo on charts called the compass rose.

It correlates nicely with a deck compass as the rose has both magnetic and true readings…Its a double flower.

So I find your original post kind of cute. Use on your GPS whatever you are using on your backup compass, map or chart.

Primary suggestion
Right. Coordination, usually of magnetic north across map - deck compass - GPS is recommended once past the not real idea there are other reasons inside the GPS for other choices.

One writer advised against juggling different systems for arcane reasons, was forgetting what you were or are doing or having conversion factors unwieldy in times of stress.

I carry extra batteries.

But NOAA paper maps are available online. Consult there or copy if detail is more extensive than the GPS.

The obsolete Blue Charts and obsolete 76csx would spring great detail into view as we approached an overfall/tidal sluice…sometimes not viewed ashore before watering.

To check paper is best. or review. I go on Gates Tours with Streeets n Trips from not double checking the route. Once leading to a 6 foot snow drift 40m miles to backtrack into a secondary approach.

Check your Datum
IF your GPS is coming up different than your map your gps isn’t running the same Datum as your map. If you want to use USNG set your GPS to MGRS (Military Grid Reference System). It is the same as USNG but your Datum still has to match your map. My guess your not set to NAD84 which is most common maps and remember if your location has changed much since 1984 the map won’t be accurate. Again I would suggest you find someone to help you. getting partial questions on a forum when you don’t have a base knowledge is just going to confuse you.