Hummingbird GPS question

[wagn]

I'm having a problem with the internal GPS on my Hummingbird 587ci. When in chart mode, and looking at the built in maps, the maps don't seem to line up with the real lake. For example, it may show my boat travelling up on the shore instead of being on the water.

I hope this makes sense. It's kind of hard to describe.

I want to upgrade to a navionics chip, but there is no point in having lake contours if I can't get the GPS to accurately show my location on the lake.

Has anyone else had this problem or know how to fix it?

Thanks

[txbass1]

Only advice I can offer is to make sure that you have the latest update loaded from Humminbird.com.

[Wayne P.]

Parts of those maps and some of the Navionics lake maps come from several sources and are only as accurate as the source maps.

When you find a body of water to be different than the position shows, use the map offset feature in your menu to move the map to the correct position on your display.

Turn off the offset when on another body of water to check for any position errors.

[Tpayneful]

Wagn,

   I was on canals next to Lake Okechobee and the gps said that we were on land.  Follow Wayne's advice and use the map offset function to move the map to fix the problem.

[Fishing Rhino]

When I was at the Road Trip, Pickwick Lake was one of the "hot maps", and I found everything to line up, boat position over shoals, at buoys, in coves and channels.

Recently, when I got home I went to a Cape Cod pond that was also "hot mapped", and again, the boat position on the screen matched the actual position on the pond.

Last week, I went to another Cape pond that was not "hot mapped", and found the boat position to be off by a couple of hundred feet from what was displayed on the screen.

Sooo, I marked my favorite spots once I was actually over them.  From now on, I'll be able to navigate directly to those positions.

[wagn]

Thanks guys. I thought it might me something as simple as that.

I saw the map offset feature in my Manual, wasn't sure if I needede to do that.

So if i understand correctly, getting the navionics chip may help fix some of the maps, but I might still need to manually line up the map on certian smaller bodies of water.

Thanks for the help

[Long Mike]

Rhino, when we were at Pickwick the lake level had risen so much that, in one cove, my GPS showed that we were a hundred yards inland.  It was correct.  Ghoti caught a nice base that was hanging around a Bar-B-Que pit.  I felt sorry for those folks whose RV's were swamped.