GPS questions'

Ok hopefully the last question about me and my GPS :)) I got the north map set for and took off for the lake. Does anyone else have issues with the maps being way wrong. As an example Carlyle lake in IL is huge. There is an old pump silo out in the middle of the lake and it also shows on the map. Problem is when I pulled up next to the silo and then looked at the gps It showed me about 1/2 to a mile past is already. Would this be the map being wrong or is it a possiblity that something is set wrong in my GPS???? Also the cursor never seems to be pointing the right way if I am going slow.

Make sure waas is enabled. Check correct datum settings. If this does not correct it then, Houston we have a problem. My little Garman e-trex and its map are dead on. I also have a Humminbird 161, it is dead on as well. Both had the map already installed when I bought them.
THE BANDIT

WASS was enables and the datum setting is WGS-84 which is the default. Not sure if its a map problem or GPS problem. BTW I have the lowrance H2OC model. Appreciate the response so far

Mine is dead on most of the time, but there is one place I go to, that when the gps show's I'm at the current bridge, I'm actually at a old underwater bridge. I figured it must be the map.

When you're out again, press the PAGE button till you get to the one that shows the satellite reception. It also shows you what the accuracy is in feet, or at least how accurate the device itself thinks it is. If it is within 30 feet and your map shows you to be half to a mile off, then I'd say it's the map. I know there are areas where my reception really stinks and accuracy is off by a good bit, but I don't think it's ever been as much as half a mile. Oh, I have the Lowrance H20.

Most likely the position of the silo was wrong on the map they used to make theirs. GPS is far more accurate than the maps.

Try Creating Your Own Waypoint For The Silo And See How Close It Brings You To It This Way!

look in your settings to see if you are running navagation up or direction North up that should clear your problems

Let us know what you find out. That is how good information developes, by sharing answers to problems.
THE BANDIT

I have an old Lowrance 100 and when down loading some way-points it had some up on the banks, I think it was the type of coordinates I was using? It was a decimal off all points.
Rowdy

Mmjoker, I didn't see you or anyone else mention if it seems accurate in other locations you are at? I would think if you tried it at other obvious landmarks and it's ok there, then it's just a map error. If it's off by half a mile everywhere, then I'd send it to the factory for calibration or at least call and ask the factory for advice. That's just my 2 cents. Good luck with it!

I also have Lowrance Create maps and they are off at several locations. I have watched it make trails along side of the map roads and sometimes they can be more than a 100 yards off. When I travel this route at another time, the trail is marking another one on top of the first one and is very good at duplicating its co-ordinates but the map program is off and still shows me driving along side of the road instead of on it. Most of the map roads and places are right on but some of the map is way off.

I found my book, Check the Position Format and Position Correction Factor (PCF)
Rowdy

Try checking it against the intersection of two major roads very close to the lake. These are usually verified every few years.